Foundation Design

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Guide to Foundation Design | Column

Footings

Foundation Design

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Foundation is the base of any structure. Without a solid foundation, the structure would not hold for long. We have to be very cautious with the design of foundations because our entire structure rests on the foundation. The job of a foundation is to transfer the loads of the building safely to the ground.

Laying of Column Footing Reinforcement | Foundation Design

The strength of the foundation determines the life of the structure. As we discussed in the earlier article, design of foundation depends on the type of soil, type of structure and its load. Higher the load bearing capacity of the soil, the larger the load it could safely carry.

Foundations are basically divided into Shallow Foundations and Deep Foundations.

In this article, we are going discuss the step by step guide to Column Footing Design for a shallow foundation.

Reinforced Concrete Footings

Footing comprises of the lower end of a column, pillar or wall which i enlarged with projecting courses so as to distribute load.

Footings shall be designed to sustain the applied loads, moments and forces and the induced reactions and to ensure that any settlement which may occur shall be as uniform as possible and the safe bearing capacity of soil is not exceeded.

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In sloped or stepped footings, the effective cross-section in compression shall be limited by the area above the neutral plane, and the angle of slope or depth and location of steps should be such that the design requirements are satisfied at every section.

Design Procedure of Column Footings | Foundation Design

Here is a step-by-step guide to Column Footing Design:

Column Footing Plan and Section | Foundation Design

Step 1

Area required for footing Square = B = (w+w1)/P0

Formwork

Challenges ? We

Have The Solutions !

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Where, Po = safe bearing capacity of soil

w1 = self weight of footing

w = self weight of footing

For Rectangle = b/d = B/D

A = b x d

Net upward pressure on the footing q/p = W/A

Step 2

Bending Moment

Critical section for maximum bending moment is taken at the face of the column

For a square footing,

Mxx = q x B/8 (L – a)2

Mxx = q x L/8 (B – b)2

Myy = q x B/8 (L – a)2

Step 3

To fix the depth of the footing shall be greater of the following:

Depth from bending moment consideration

d = √(M/Qb)

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Depth from shear consideration Check for one way shear

Check for two way shear or punching shear

Critical shear for one way shear is considered at a distance ‘d’ from face of the column.

Shear force, V = qB [ ½(B – b) d]

Nominal shear stress, Tv = k . Tc

Tc = 0.16√fck

Step 4

Check for two way shear

Critical section for two way shear is considered at a distance at a distance d/2 from all the faces of the column.

SF, V = q [ B2_{– (b + d)}2_]

SF, V = q [L x B – (a + d)(b + d)]

Nominal shear stress, Tv = V/2((a+d)(b+d)d) ——- {for a rectangle

Tv = V/4((b+d)d) ——- {for a square

Tv = k . Tc

k = 0.5 + β > 1 ; [Beta β = ratio of sides of the column

Tc = 0.16√fck

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columns, concrete, Design of Column footing, Footing, Foundation, Foundation Design, Guide, Guide to Foundation Design, Importance of Foundation Design, RCC Footing Design, Steel

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COMMENTS (364) RELATED POSTS

Civil Projects Home »» Building Construction »» Guide to Foundation Design | Column Footings

#1 by Mr.atiq on June 17, 2010 - 12:41 am

salam & hi,

can u explain me … that the proceture to calculate total load of single story building + how to determine the area for (width of foundation , depth of foundation , thickness of block & number of off sets)…

atiq….

#2 by BenzuJK on June 17, 2010 - 3:05 am

Hi Atiq,

Foundation design is a complex process. It depends on the total load on a particular foundation as well as the Safe Bearing Capacity of the soil.

For example, a single storey building foundation with hard soil, where total load on footing does not exceed 300kN, a footing pit of 1M X 1M at a suitable depth upto hard strata would be sufficient. The pit would have a 6″ layer of PCC. On top of that, you would place a mesh of steel consisting of 8 rods each of 10mm diameter on both sides. Then place the column steel frame on top of it and tie the column bars to the steel mesh. Pour 6″ of concrete and let it harden. Then you can go for either tapered footing or block footing. Total thickness of block should be 15″, including the 6″ you of RCC poured earlier. So, for a single storey building whose load does not exceed 300 kN, and the soil strata is hard, the above given design should be sufficient.

#3 by Asit Baran Saha on January 3, 2011 - 3:13 am

The concrete should be poured in one go.

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If somebody don’t tie the column reinforcement to the mesh below then what will be the possible type of failures.

#5 by BenzuJK on March 29, 2011 - 2:13 pm

Never observed any such failures in structures. So, am unaware of that. Maybe Google Search might help…

Practically speaking, column reinforcement is embedded in many feet of concrete. Ensuing footing would be weak, but I doubt if it would fail.

Cheers!

#6 by Amba on March 15, 2012 - 1:48 am

Yes! you are correct! If at all the workman ship does not satisfy , like the plumb of the column/building), there are no failures observed.

#7 by Ajaynder on August 26, 2011 - 1:09 am

There is no failure but the eccentricity of the column reinforcement might be disturbed, thats why its important to tie the reinforcement after alligning to the center line.

#8 by BenzuJK on August 27, 2011 - 3:58 am

Hello Ajaynder,

When the eccentricity of the column reinforcement gets disturbed, it leads to structural cracks which results into structural failure. Structural failure does not just mean that “the structure would collapse” but it also means that the structural components like beams or columns in a structure are damaged which affects their strength considerably.

Cheers:) BenzuJK

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If u do not tie your column to the bottom mesh… then there will be joint failure (probably cracks in diagonal direction will arise that is shear failure) between column and the other member.

#10 by meenakshi on September 20, 2012 - 2:32 am

bharat bhushan jindal :

if we didn’t tie the longitudinal reinforcements of the column,then the bars may buckle and column will tilt..i hope u got ur ans

#11 by kuttan on June 17, 2011 - 3:21 am

Hi Benz,

I am bit tensed aftre readiing this article. My 2 story building (1300+1200 sqft) foundation design consists a mesh of with 8mm rods and column steel frame of 12mm. Is this is sifficient for this building? there are around 17 columns in the foundation with beams connecting all the columns. Reammy appreciated your reply on this ASAP.

Sasi

Hello Sasi,

8mm rods can be used for the footing mesh. The number of steel rods change with the thickness of the mesh. So the mesh being 8mm or 10mm is not an issue. It all depends on the load coming on a particular footing. The load on every column is different depending on which we calculate the total quantity of steel required. If your engineer is qualified enough then don’t worry, he will take care of it. Your building will be safe.

#13 by kuttan on June 20, 2011 - 4:00 am

Hello Benz,

Thanks for the quick reply. Just one more quiry. The beam size connecting all the columns are 30cmx20cm with avg span of around 4mts. Is it sufficeint dimension? just wanted to have second opinion. Also whether we need to extend the column pillars to to the roof level? My architect says its

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not required. Instead we can have 15 cm concrete belt with some additional rods running through out the plinth. Please advice.

#14 by BenzuJK on June 25, 2011 - 10:31 pm

Hello,

This shall be fine. You can proceed with the construction. I don’t think there would be any problem. All the best!

#15 by kuttan on July 6, 2011 - 5:15 am

Hi Benz,

Thanks for your valuable advice. May need your help going forward. If you don’t mind can I get email id? Please reply to [email protected]

#16 by BenzuJK on July 6, 2011 - 11:00 pm

Hello Mr. Kuttan,

You can always keep in touch with me through my site. You can ask any questions that have regarding the construction field. Will try me best to help you whenever possible.

Benzu

#17 by Romal on January 5, 2015 - 10:47 am

Dear Sir,

I have 4 story building the foundation slab for each column is 1m2 and deepness is 70cm2 and beams connected in foundation each column 40x40cm with 6 each of 14mm rebar . it has totally 15 columns the size of the columns are 30x40cm each column has used 8 each of 16mm rebar and the soil of the fundation is strong. now please advice can i build one other story at the top of it to became 5 story. THANKS

#18 by peris on July 6, 2012 - 1:05 am

hi,

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Regards, Peris

#19 by BenzuJK on July 6, 2012 - 11:52 am

Hello Peris,

Guide to building design | Structural Design

#20 by amitava kar on July 10, 2010 - 8:25 am

I need to design a storey building how the load calculations r carried out that is coming in the column can pls tell

#21 by gunasekaran on March 5, 2012 - 4:50 am

how to make the design of foundation,footing, collum, beam, slab @and it tk.which the bar using for design in the structure.

#22 by BenzuJK on March 7, 2012 - 1:29 am

Please check out:

Building Design and Construction | Structural Design guide

#23 by sateesh on July 20, 2010 - 11:31 pm

Hi,

Please explain me the design proedure of Generator building. what are the loads i have to consider. Thanks,

Sateesh

#24 by BenzuJK on July 28, 2010 - 2:06 am

Generator Building is a place where heavy machinery is placed. Firstly, you will have to study the kind of machinery that will be used in the Generator Building. Only then can you estimate the load on the building.

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Once you know the average weight of the machines and the number of machines that your design supports you can then move on with the load calculations. More than the live load of the workers or technicians, consideration of the dead load of the machinery plays a vital in the design of Generator Building.

#25 by ikoto on May 12, 2011 - 5:49 am

can footing depth vary in same builing

#26 by deepa on August 3, 2010 - 3:13 am

Its good to find the whole design part in this if we hve images of various kinds of footing it wl be useful.

#27 by rajendra on September 18, 2010 - 11:47 pm

what will happen in footing if we provide larger dia long side and placed down and small dia to short side and placed above ?

#28 by Mani on November 1, 2010 - 3:58 am

is Achorage requried for a 6feet x 6feet x 1.3feet footing. also kindly advise whether anchorage required for columns, plinth beams, and tie beams. kindly advise.

#29 by vinod on November 18, 2010 - 12:57 am

why we do grouting at the column base plate??

#30 by BenzuJK on May 21, 2011 - 10:22 am

Grouting at the column base plate helps in strengthening and stiffening of the column base. This could help in avoiding flexural and structural failure.

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dear sir,,

i want to build up a flat RCC roof for roofing area of 43′.4″x31’3″. so i need the rod calculation formula and also the roofing diagram.

#32 by Suman Dutta on December 22, 2010 - 6:14 am

Dear sir

I want to build up a home of two storied building , area 30’x25′. so I need the rod calculation formula and also roofing diagram.

#33 by Pritam Roy on December 23, 2010 - 8:25 am

Dear sir

I want to build up a home of two storied building , area 22?x52?. so I need the rod calculation formula and also roofing, foundation,beam, column diagram.

#34 by rajendravkurup on March 3, 2011 - 12:35 am

Pritam Roy :

Dear sir

I want to build up a home of two storied building , area 22?x52?. so I need the rod calculation formula and also roofing, foundation,beam, column diagram.

Wouldn’t it be a better idea to contact a professional? It would be safer and cheaper to build according to a perfect design of an experienced professional.

I know an experienced Civil Engineer who is also an Architect, Javed Kachchhi.

http://www.architectjaved.com

#36 by Riji Sajan on December 28, 2010 - 1:01 am

please explain the the design three storey building column footing,plinth beam roof slab etc.

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i need details load, vibration and wind force calculation tank foundation as folloing: 1.0 Foundation size = 8500 mm x 3200mm and need height

2.0 need re-bar datails fourmula 3.0 tank weight = 13 ton

i hope my request will receive kindly consideration by you.. Regards

Ram

#38 by Aseged on December 30, 2010 - 6:56 am

Hello

I am designing a G+1 Residential building that rests on a rock and the maximum column load I have got is 200KN. Since it is difficult to excavate the rock what is the possible solution and what minimum dimension of footing shall I use

#39 by Asit Baran Saha on January 3, 2011 - 3:05 am

Hi

pl. elaborate method of design of a combined footing connecting more than two cols. in line

#40 by Mano on January 3, 2011 - 5:41 am

can I give me an example for plinth beam design for a building foundation

#41 by fanka kongnyuy on January 11, 2011 - 4:02 am

sir,

i wish to know why it is that when designing footings reinforced bars as placed closed to where the pillar will stand

#42 by fanka kongnyuy on January 11, 2011 - 4:05 am

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#43 by hari prasad on January 26, 2011 - 6:38 pm

I want to know waht is the load bering capacity of the rcc roof slab of 150mm thick simply supported

#44 by rk khurana on February 7, 2011 - 9:17 pm

sir/madam,

hi, I wish to know if in old structure foundation bolts and concret on surface damaged so to renew the foundation for steel structure. what can be done?

#45 by Ashish on February 10, 2011 - 12:30 am

what is the technical name of column between foundation footing and plinth beam .Is it stub column? Ashish

Hello Ashish,

The column between foundation and plinth beam is called a stub column. It is squarish in shape. The dimensions of the column changes above the plinth beam…

#47 by Kasi.Maheswara rao on February 10, 2011 - 1:35 am

Hi,

We have one old building without columns slab rest on brick wall. It’s constructed before 10 years, now walls are formed cracks the building is in oil and gas plant no of times wall chipping and reconstructed for windows and Ac opening pls suggest the building is suitable for living or need to dismantled

#48 by rajendravkurup on March 3, 2011 - 12:50 am

dear sir,

i want to design a pre engineering structure on top top of r c c framed design. size is 120m x 31m. please help me to find out how many columns and footing size to find out. load of pre engineering structure is 60 ton.

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#49 by raghu on March 3, 2011 - 10:58 pm

can i have the eccentric footing design procedure

#50 by Labannya on March 9, 2011 - 11:16 pm

is 5″ brick wall safe for supporting a RCC slab? if not then why?

#51 by BenzuJK on March 10, 2011 - 4:04 am

Hello Labannya,

Supporting a RCC slab on a 5″ brick is unsafe and not practical. It has to have a Column and beam structure above which RCC slab could be casted.

The reason is that there are heavy chances that the brick wall might slip which would lead to the collapse of the structure. I hope would find the answer helpful.

#52 by bharat bhushan jindal on March 20, 2011 - 5:23 am

Hello….

what about the supporting of slab of shorter side span of 20 ft on brick columns.

You can do that. A large brick column or a fat brick wall… But please consult with a local engineer for accurate calculations…

Cheers!

#54 by Sheeja on March 22, 2011 - 10:41 am

Sir,

I would like to know the follwing for the calculation bearing pressure below a footing, to know whether the pressure is below the safe bearing pressure of soil.

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unit weight of RCC and 15 is the unit weight of soil.

2. Whether weight of soil above footing, i.e, weight of backfilling to be taken.

I didn’t understand your question. From what I could understand,

Weight of backfilling is negligible. I won’t affect the footing much… 15 kN/m2 is not much, when a typical building load per square meter can reach above 1000 kN/m2. Even for a simple 3-storeyed structure, loads on columns routinely cross 500 kN/m2

I believe a RCC design book would help you… Cheers!

#56 by Vicky on March 31, 2011 - 8:56 pm

what should be the design load to be taken for the footing design of a single storey, two storey, and 3 storey residential building ?

#57 by Thomas on April 6, 2011 - 12:03 pm

I want to replace 3- 6×6 bearing posts in the basement of a 3 story wood structure. They are currently sitting on 2×8 wood on an existing 1-2 inch old concrete slab floor. I want to put new footings under posts. I’m using 6000 psi concrete mix, what size footing width x length x thickness should they be, and configuration of rebar?

#58 by vijay on April 22, 2011 - 9:17 pm

what will the column footing size genraly taken in 3storied resedential building

#59 by BenzuJK on April 24, 2011 - 4:44 am

Hello Vijay,

The column footing size taken for a three storied building depends on the spans i.e. column to column distance. Generally the size of the column footing is taken as 4’6″x5′ for 4m c/c

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#60 by tirumala on April 30, 2011 - 4:15 am

other than main and distribution reinforcement any other re bars will be there in footings

Hello Tirumala,

There are no other type of reinforcement bars in footings apart from main and distribution bars. Cheers:)

#62 by P.cHHETRI on May 3, 2011 - 10:37 pm

I am designing 3 storeyed building using staad pro, and sap software, I have probelem in defining load combinations. Can anyone one help me out..

#63 by Ashok R.Sharma on May 11, 2011 - 9:09 am

Hello,

How to calculate the total load will come on footing?

Four loads are to be considered in order to measure total load on the footing:

1) Self load of the column x Number of floors 2) Self load of beams x Number of floors 3) Load of walls coming onto the column 4) Total Load on slab (Dead load + Live load) Benzujk

#65 by Imtiaz on May 20, 2011 - 11:11 am

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#66 by srinivas on June 8, 2011 - 2:10 am

Sir, i constructed a single storey building, build up area is 900 sq.feet, the soil is hard and rocky, the depth of the footing is 6 feet, column footing size is 4’x4’feet, number of columns are 9, each column size is 12’x9′, rods used in column are four 16mm and two 12mm. plinth beam tie up with all eight columns one column is isolated, it is in parking area ( the rooms are 2 feet height compared to parking area ).

i would like to know plinth beam is really required for that isolated column and how many floors can i construct on this foundation. please give your valuable opinion.

thanking you, srinivas.

Hello Srinivas,

Firstly, you need a plinth beam to tie the isolated column because if you dont do so, it might result into bending of column resulting in collapse.

4’x4′ footing size is pretty small. Your column steel design is good. If the column c/c are not more than 12′ than you could go for G+3 without any hesitation.

I hope the answer was helpful. Benzujk

#68 by Ringwang on December 22, 2011 - 2:14 am

please can u tel me what is G+3. all your answer are very usefull

#69 by Abdul on September 27, 2012 - 11:20 pm

what does G+3 or G+2really means? i am confused..its actually new term for me..thanks

#70 by khan on June 11, 2011 - 1:06 pm

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is there two shear in any other RCC member apart from footing? thank you

One way and two way shear is found in beams and columns too but punching shear is only evident in between a column and a footing.

I hope it helped. Benzu

#72 by khan on June 11, 2011 - 1:08 pm

what is the difference between one way shear and two way shear? thank you

#73 by Bassel on June 13, 2011 - 12:43 am

Dear Sir,

in case of having 3 pillars supported to on founation in triangle posetion, can please provide me the hence of the design in this case

Thanks Bassel

#74 by khan on June 15, 2011 - 12:38 pm

what is the main difference between one way shear and two way or punching shear,when we have such shear in buildings?

thank u

Hello Khan,

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It generally causes cracks in the RCC members. Two way shear is said to occur when the horizontal stresses occur from either sides of the members causing it to crack or result in crushing of the structural members if not designed properly.

Punching shear

It generally occurs between a column and a footing. The column tries to punch itself inside the footing because of the excessive stress on it. This could cause weak joints between columns and footings and also lead to structural failure.

#76 by mohan kc on June 20, 2011 - 9:24 pm

hello, i wanna know the design procedure of doglegged staircase with rcc arrangement

Hello Mohan,

Check this link on Design of RCC Staircase

Guide to design of RCC staircase

#78 by tona.ahmed on June 29, 2011 - 10:11 pm

thanks for the post. I want to design the reinforcement for upward (negative) reaction. (As it happens in Factory shed where both positive and negative reactions should be check.)

need a technical help.

#79 by Softy on July 5, 2011 - 6:46 pm

If somebody don’t tie the column reinforcement to the mesh below then what will be the possible type of failures.What should be the design load to be taken for the footing design of a single storey, two storey, and 3 storey residential building ? I hope you can answer all my questions.

#80 by BenzuJK on July 6, 2011 - 11:05 pm

Hello,

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results in its stability and strength. Structural cracks might appear if one fails to do so.

As i have already explained earlier, four loads are to be considered in order to measure total load on the footing:

1) Self load of the column x Number of floors 2) Self load of beams x Number of floors 3) Load of walls coming onto the column 4) Total Load on slab (Dead load + Live load) I hope I have made it clear.

Benzujk

#81 by MANOJ on July 6, 2011 - 9:53 pm

Hi,

i have to construct a house which has houses on both sides. what is the design for foundation and columns with out disturbing the sides of other houses. the critical situation is that i cannot afford space between the walls.

#82 by kuttan on July 7, 2011 - 5:03 am

Hi Benz,

Thanks for the clarifications on earlier comments. I have my foundation ready now. Initially I planned for the red bricks for building the walls. Now changed it to cement blocks with MSand for plastering. What are the things I need to be careful while using the cement blocks with M Sand?

Hello Kuttan,

The only care you will have to take while constructing your walls with cement blocks is checking the alignment of the walls. A wall with cement blocks is more prone to collapse as compared to the red brick walls if the alignment is not proper.

#84 by cabrin on July 8, 2011 - 12:42 am

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#85 by hari on July 12, 2011 - 7:41 am

which structure is more safe & cheap in two story building. 1. load bearing walls (B.B).

2. frame structure.

Hello Hari,

Preferably, you should go for Framed Structures and avoid Load bearing structures. Load bearing structure is safe for a two story building but framed structure would be the safest. Though there is a little difference between the construction costs but keeping in mind the long term usage, one must go for Framed Structures.

Also, the disadvantage of going for Load bearing walls for a two story building is that the walls get thicker and the inner space decreases. Since land has become so costly, going for a framed structure would be a sensible choice.

#87 by S. S. Ahmed on July 25, 2011 - 12:36 am

Dear Sir,

I would request you to advise me about the foundation plan. what type and size of foundation required to carry out the 300Ton weight?

#88 by fazil on July 26, 2011 - 3:45 am

Dear sir,

in a school building some of the footings are coming over a sloping rock.here the strata is hard but the slope may leads to slipping of footing .so wat will be the possible solution that i want to follow?

Hello Fazil,

The construction can be very well executed in a rocky terrain. You should keep one thing in mind while constructing on a rocky and slopy terrain; the rock which is being used for laying the foundation is not a loose rock, this could lead to structural failure. But if the rock is hard and solid but has a slope, then you

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need not worry about it. It would not affect the strength of the construction. I suggest, before you plan on initiating the construction, you should go for land surveying and get the important details which will help you figure out what kind of foundation is to be laid and if the construction is feasible in such a site. If you have any further questions regarding the construction, you are most welcome….

#90 by naseer on August 6, 2011 - 5:07 pm

How can I design three storey building

Hello Naseer,

Check these articles. They may be of help to you.

Load calculations for foundation design Guide to Foundation design

Cheers:)

#92 by M.Thirumurugan. on August 13, 2011 - 11:45 pm

Dear madam/sir

I strat next month my house work.house area is 1300 Sqft.kindly request to yoy please send footing and column sizes and reinforcement details and distance of every columns and roof slab thickness and reinforcement details. house size is 9m*12m

Thanks and Regards M.Thirumurugan.

I would kindly suggest you to contact a certified Civil Engineer for the work. Check: http://www.architectjaved.com

Mr.Javed is an experienced Architect, civil engineer and an Interior designer. Email: [email protected]

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#94 by anuj on August 24, 2011 - 11:18 pm

how can i calculate column loads????

it would be very nice if you can give me some reference and your ideas

#95 by Nilesh Khorasiya on August 31, 2011 - 6:16 am

Sir,

As a general practice, we used to make Starter (of approx. 100mm ht.) for column formwork. But, from some expert, it is said that ht. of starter would be of 500mm ht. as per standard.

Could you pl. explain the exact mathods. Thanks & Regards….

#96 by gopal singh on September 12, 2011 - 11:40 pm

dear sir,

I would like to ask you that below o.oomtr lvl should a part of colm be considered as footing,as it is written in chinese code.

#97 by BenzuJK on September 15, 2011 - 6:43 am

Hello Gopal,

The pedestal below the column is called a footing. The part of the column below the ground is still called a column and a footing.

Cheers

#98 by boblu on September 16, 2011 - 12:52 am

how to determine the foundation depth?

#99 by BenzuJK on October 1, 2011 - 12:10 am

Foundation depth is determined by calculating the total load on the foundation. After the load calculations, you will be able to set the dimensions of the foundation (Length, width and depth). Hope that’s clear.

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Check out this article:

Calculation of loads for Foundation design

#100 by abbas on September 23, 2011 - 6:26 am

abbas :hello friends i find this website very interestingi ve learnt many things through it.thank you for sharing your experiences with us.i am a newcomer from senegal:

#101 by BenzuJK on September 26, 2011 - 1:36 am

Hello Abbas,

I am glad the site was of help to you. Do keep visiting and sharing your views. Cheers

#102 by kishor on October 6, 2011 - 1:28 am

please tell me the critical situation of footing designs like footing between two walls in which one is already constructed and other we have to construct with L shape

#103 by Sarfraz Ahmad Ansari on October 6, 2011 - 3:47 am

Very Nice……….

what should be the design load to be taken for the footing design of a single storey, two storey, and 3 storey residential building ?

#104 by BenzuJK on October 10, 2011 - 8:12 am

Hello Sarfraz,

Check this article. This will answer all your queries:

Load calculations for footing

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#105 by Sikandar Ali on October 9, 2011 - 6:05 am

Hello,

What are the general specifications for length of L for short columns.Because in some drawing I dont see the length extended inside footing.Suppose columns length is 3 m high then how much should be bended (L) inside footing.

Regards

#106 by Bashir on October 13, 2011 - 2:57 pm

thanks for your explanations on some key structural issues,they simple,concise and straightforward.i wish more from u.

Hello friend,

i need a comprehensive examples on how toanalyse and design a structure .

The article is highly educative,hope to learn more from you with something new.

#109 by BenzuJK on November 6, 2011 - 3:37 am

Hello Bashir,

We will try and put up examples on analyzing and Designing Structures.

Check this out. This might be of help to you.

Guide to Building Design

#110 by Kurian Abraham on October 31, 2011 - 1:02 am

I am building a 2 storey house in a land that was previously a paddy field. It was slushy / marshy land in which I filled with soil in 2001about 7-8 feet deep. Now i am planning to construct this house and do you think I need to go in for any specific deep foundations. One person suggested column foundation that goes to about 10 feet below ground. Another suggestion was well foundation. Please comment.

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Thanks, Kurian

#111 by BenzuJK on November 12, 2011 - 9:54 am

Hello Kurian,

Well Foundations are pretty outdated. You must preferably go for Pile foundations. Concrete Pile Foundation will be perfect in your case. Raft Foundation can also be used but since they are little more expensive option as compared to Pile Foundations, you could avoid them.

Let us know if you have any more queries.

#112 by Dumdum on November 18, 2011 - 6:01 am

Can one use 12mm reinforcement bar for columns of three story building?

#113 by BenzuJK on December 1, 2011 - 11:27 pm

12mm reinforcement bar for columns can be used for three storey building. It depends on the load coming onto the columns. Making an appropriate column layout is very important. 12mm reinforcement bars can be used if the distance between columns is appropriate.

Check out this article. It will surely be of help to you.

Thumb rules for making a column layout

#114 by daryl on November 26, 2011 - 12:18 am

Some references use net allowable soil pressure for the design, that is allowable bearing capacity less surcharge and the weight of the soil backfill but some does not consider deducting the weight of the soil backfill. When do we need to consider deducting the weight of the soil backfill from the allowable bearing capacity.

Thanks!!!

#115 by kaleem on December 5, 2011 - 7:37 am

iam consturcting single story building at the edge of minor irrigation tank ,there is silty soil and room size is 24′-0″ x14′-0″ ,what depth ,size footing needed please reply

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#116 by p.velladurai on December 6, 2011 - 8:50 am

hai frds

this website is very useful for engineers we r learn to our doubt clarifications through it. im a new comer from tuty in tamilnadu

#117 by descravel m on December 8, 2011 - 9:03 am

Dear sir,

what is the difference between sloped footing and flat footing.

#118 by BenzuJK on December 14, 2011 - 7:43 am

Hello Descravel,

Isolated footings are of two types: 1) Tapered footing

2) Stepped footing

Tapered footing which I guess you are referring to as sloped footing, is used in case of small constructions such as bungalows, duplexes or G+1 structures. The reason why it is used in smaller structures is that it is economical as compared to stepped footings.

Stepped footings

They are used in case of multi-storied constructions. Use of Tapered footing in multistoried buildings proves to be uneconomical.

#119 by Arun Kumar on December 10, 2011 - 8:06 am

For seven storied residential framed structure with RCC columns 5.00 meter apart, which type of foundation would be required on moderate type of soil. If raft foundation is required, then what would be adequate depth of the raft ?

Hello Arun,

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Raft foundation is used only in case of extremely weak soils. Isolated footing can be used even for a 10 storey building if the soil is moderately strong.

#121 by Tarun Kumar Bhunia on December 16, 2011 - 9:53 am

I have booked one flat of a residential six storey building.The size of its colums is 12/16,its foundation is 7ft deep in hard soil,it has seperated colum footings.Is the building safe? Colums are cons

tructed with 8 tmt bars(four of 16mm ,and four of 12 mm).Please help.

#122 by Dinesh Trivedi on January 16, 2012 - 4:26 am

Hi there,

I am planing to construct my house on plot area of 20 ft x 20 ft = 400 sq ft, ground, and 400 sq ft. first floor, total Rcc area as per architact is 990 sq.ft aprox. I would like to know how much steel, cement sand and aggregates will be required so that I know the cost of material.

Your earliest reply will be highly apriciated, Thanks

Regards Dinesh Trivedi.

#123 by BenzuJK on July 26, 2013 - 5:59 pm

Hello Dinesh,

The structural design depends on the building plan. WE cannot make assumptions. It is all calculated and required professional knowledge. Every project is different and has to be dealt separately. The quantities of sand, cement, steel and aggregates require a detailed analysis of the structural design. I hope what I am saying is making sense to you.

Civil Projects Online has made things easier for you. It has launched Architectural and Structural Design Services at minimal costs. You can also receive expert advise.

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#124 by Victor on January 25, 2012 - 1:45 pm

Hello

Please, to design a foundation for a Generator, is any special requirements, from Ontario Building Code ? Thanks

#125 by S.rama on January 28, 2012 - 12:01 pm

Sir, i want construct a G+4th storey building, build up area is 3973 sq.feet in 23’9″x158’5″ , the soil is not hard ,from entrence in right side 4’6″ wide open duct and left side 6’9″ wide

passage. And, i want to provide 56 nos columns accrding to room(12’0″ x 12’0″) and their corner. and want also to provide 9.84″x17.71″(16mm dia) RCC column in outer wall. am i right or wrong

thank you ! S.rama

#126 by BenzuJK on July 26, 2013 - 5:57 pm

Hello Rama,

The structural design depends on the building plan. WE cannot make assumptions. It is all calculated and required professional knowledge. Every project is different and has to be dealt separately.

Civil Projects Online has made things easier for you. It has launched Architectural and Structural Design Services at minimal costs. You can also receive expert advise.

Architectural and Structural Design Services

#127 by Lakshmanan on January 30, 2012 - 9:15 pm

In my house plan the contractor has drawn for the hall of 14 ft by 30 ft approx with 4 pillars at about 10 ft distance each and on other parallel side 3 pillars at 15 ft distance each and each pillar from foundation column has 6 no.s of 12 mm rods in 9″ by 12 ” column/pillar; Whether 12 mm rod vizag/TISCO make ok whether any special care to be taken in concealed beam on lintel or roof level required. How to cross check my plan if it is correct without defect………….lakshmanan

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hello Benz

i want to know the procedure of machine foundation for 11kv isolator machine and transformer. . in some textbook they simply consider 0.12percent GA. . how the ecentricity calculation for this point load and hence moment. . also for mode of vibration and frequency check. .please guide me

#129 by yogananda on February 2, 2012 - 9:39 am

hello friends

any one help me for design of pile cap. . i designed pile cap by embedded piles to pile cap and calculating the max reaction of pile per meter and hence moment with respect to ecentricity for this i designed steel . . is this procedure correct . . also in some books they will designed as slab by just considering as max BM respect to simply supported condition . . which is correct

#130 by Roland on February 2, 2012 - 3:38 pm

This is about ground floor column moments. We use column height from ground level to second floor in analysis of multi-storey bldgs. This results to column moment values at ground level. Now when we design the footing, we use this same value though the footing level is way below the ground level. Should we not neglect this moment as the ground slab and soil can provide rigidity and disperse column load moment when it reaches the footing level?

#131 by g yousal on February 3, 2012 - 6:56 am

dear benz,

i am building a 3 +1/2 storeyed house om a hilly slope. The foundation mesh designed by my architect is 6′ x 6′ of 16mm rods and the columns are 9”x16”( 4 nos 16mm & 2 nos 12mm) size and beam size including slab casting is of 9”x18” ( 6 nos. 16mm ) The maximum beam length is 15’4”(c to c)’. All the beam placements are in a grid formation. Please let me know the following :

1. what do you mean by tying the column end to the foundation grid? (My architect says the cloumn end needs to be just centered on to the grid and the footing pyramid built ( i.e there is no tying of the L-shaped column end onto the grid) How do you do the tying?

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3. Are these rectangular shaped columns have the same structural strength as a square shaped one of same size ( say 9” x 16” versus 12” x 12” )

4. Does the placement direction of these rectangular columns ( i.e the facing of wider & narrower side ) need any specifications or can be faced as per the rooms partition requirements?

#132 by Suresh on February 3, 2012 - 10:07 pm

Hello sir,

1. Can u tel me the purpose and necessary of provide tapered footing in residential building? 2. Difference between tapered footing and block footing?

#133 by BenzuJK on February 5, 2012 - 6:23 am

Suresh :

Hello sir,

1. Can u tel me the purpose and necessary of provide tapered footing in residential building?

2. Difference between tapered footing and block footing?

Tapered footing and block footing are two alternatives that can be used for the same purpose. Tapered footing is sloped at all four sides whereas block footing is a single step footing. Isolated footings are of two types:

1) Tapered footing 2) Stepped footing

Tapered footing which I guess you are referring to as sloped footing, is used in case of small constructions such as bungalows, duplexes or G+1 structures. The reason why it is used in smaller structures is that it is economical as compared to stepped footings.

Stepped footings

They are used in case of multi-storied constructions. Use of Tapered footing in multistoried buildings proves to be uneconomical.

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i am constructing a single story building (shops) and laid foundations with 3 x 3 feet column foundations. column had 4 x #5 size dia bars, we also had plinth beam. now the owner wants me to go for double story. what minimum should i do with the foundation or with columns to go for double column, help

#135 by E.PONNAMBALAM on February 8, 2012 - 4:12 pm

HI BENZ,

IS IT THERE ANY PERCENTAGE OF REINFORCEMENT FOR A SINGLE COLUMN? AND IS IT POSSIBLE TO TIE 8 NOS OF 16MM RODS IN A 9″ X 9″ SQUARE COLUMN?

#136 by MANDLA on February 9, 2012 - 3:35 am

Hi..

This is sharat Im a civil Engineer,

SBC is calculated based on SPT test But is it the only criteria to decide SBC..

If not so please explain in detail how to calculate SBC. Depending on type of soil how do to decide SBC?? Pls reply me….

#137 by sanjay verma on February 10, 2012 - 12:40 am

how can v calculate the cement concrete of a fotting when its base is 8’*8′ and its 6” in the base and then upward sloop and 4” each bside the coloum at the top

#138 by eusemar on February 11, 2012 - 4:09 pm

hello madame,

is it too much for a 12m x 7m 3 story residential bldg to have 0.30m x 0.30 columns spaced @ 5m, 5m and 2m on the buidings longest side?

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why it is not necessary to do rubble soling beneath the footing if the same footing rest on the hard rock. and why some consultants suggest to do double layer of rubble soling beneath the footing?

#140 by africa web on February 14, 2012 - 1:56 pm

the idea behind to tie the column bars to its foundation reinforcement is to assure that the skeletal framework of a building will be acting as one, because reinforcement are assembled separately according to their usage it is ,by principle important/neccesary that this reinforcement should be secured properly to act effectively and actually serve its purpose nevertheless tieng this rebars is to avoid them from slipping from each other when subjected to excessive force/load

#141 by Paul on February 15, 2012 - 6:02 am

Dear sir,

I am planning to construct a G+1,where ground floor is 26’*22′ and first floor is 26’*36′ for that i have selected 15 pillers made of 16 mm rod square 04 nos and connecting beams of 12 mm rod square 04 nos.The ground condition is neither hard or loose.(medium).My selection is ok or not.can you please advise.

Regards

#142 by S S Chani on February 18, 2012 - 1:10 am

I find your column very useful.. my query is that I am a layman as far as the civil structures are concerned.. We have a G+2 story structure and wanna construct one more floor. Floor size is 400 Inch X 400 Inch and it has a total of 13 columns of x section of 522 sq cms each (ie 9 inch X 9 inch)

Is it advisable to go ahead with 3rd floor with existing structural strength ?

#143 by basavaraj on February 19, 2012 - 5:38 am

please suggest me which is better?

building stone wall from footing to plint or brick wall

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Dear Benzu

I want to know about following foundation Procedure. 01.Machine Foundation

a. Wt 123TN b. Suppliers Recommended foundation size 12m x 5m. Also Supply Moment x,y & z axis. c. 750rm.

02. Foundation design of Fuel storage Tank 25m dia 18m Ht , Fuel Capacity 8000kl. Thanks with best Regards

#145 by john on February 21, 2012 - 10:20 am

hi im john

if you have a beam span of 8.50 to 10.0 mtrs. in a 15 storey building, what is the ideal section of the column on the ground floor?

what is the ideal column size at 4th floor to support with a beam span of about 8.50 to 10m.? what should be the column size on ground floor if it has 8m span?

what should be the size of a column at 4th floor if it has an 8 m. span?

#146 by Kam on February 22, 2012 - 1:58 pm

Hi Benzukj,

When a foundation slab has a strip footing for exterior load bearing walls, can it be near or above a spread footings for columns. In other words can the spread footings for the columns be place deeper so it doesn’t interfere with the strip footings in the slab on grade foundation?

#147 by RUMA on February 22, 2012 - 11:18 pm

Dear madam,

in my three storied ratidential building(low land)-550 sq. ft area in one floor, 11 nos column all are 4-16dia bar(250X250mm), footing size 1.5mX1.5m with 12dia bar-200 spacing 1200 height, plinth & roof beams all are 250X2500 mm with 4-16dia bar.Is it safe? Please advise.

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how would you calculate storey shear and storey moment in kanis method of frame analysis(side sway type).I know its formula but my values are not satisfactory with my study material.Can you help me?

#149 by Suman Roy on February 24, 2012 - 3:55 am

Hello Sir

I want to know the comparison between normal single/double slope truss of IS members and tubular/pipe sections for a span of 11 m and whose two ends supports on two column. Also give related

books/journal/links information.

#150 by Mohammed Al Amir on March 1, 2012 - 2:22 pm

Hello I’m trying to build a ground plus two shopping center on a 400 meters squared piece of land. I need a building plan, how much material i need? etc..,

If you can assist I’m willing to pay for your services Thank you

#151 by megha on March 2, 2012 - 7:03 am

while designing footing why net safe bearing capacity is considered?why not gross bearing capacity is considered?

#152 by H. Bruce Campbell on March 3, 2012 - 6:36 am

Hi Benzu,

Thanks so much for your site!

I need to build inexpensive support pillars for the landing gear of a Boeing 727-200 airliner which serves as my home (web site references below). I’d prefer a method which is both cheap and relatively easy to dismantle, but fully reliable and very long lived. My sense is that each of the two main landing gear need to support a maximum of about 380 K Newtons, and the nose gear a maximum of about 133 K Newtons. My subsurface soil is moderately firm clay, but my terrain slops significantly.

At this time I’m focused on the left main landing gear task. It’s support pillar needs to be very roughly 2 Meters high and very roughly 3 Meters in diameter. The pillar tops must be concave (bowl shaped) so that

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the landing gear tires can roll a bit during an earthquake, to insure that no stress can develop, but return to the center once earth motion ceases (an anchor chain will become taut if the travel nears the pillar perimeter).

Air is maintained in the landing gear struts so that they absorb shock such as from an earthquake. The inflation height of the struts is easily adjusted so as to level the aircraft, even if the support pillar’s height changes a bit over time.

For the left main gear pillar, I’m currently considering a conventional circular concrete pad onto which an unconventional pillar is assembled as follows: Ordinary 10 cm diameter ABS sewer pipe would be stacked vertically one next to another, in an array which forms a 3 Meter diameter pillar shape, and held together with outer circular perimeter steel bands or similar. At least four steel rods would be inserted through the sewer pipes, each from the top of one side of the pillar to the bottom of the opposite side of the pillar, as diagonal members so as to prevent tilting of the pillar. The tops of the pipes would be cut so as to form the bowl shaped concave top. Each pipe would be filled with concrete and one centered reinforcing bar, or perhaps simply filled with gravel (or a combination, such as concrete fill for the center most pipes, where the tires normally rest, but gravel for the outer pipes).

A steel or similar culvert pipe to house the array of vertical sewer pipes is a conceptually easier option, and I continue to consider that. However, 3 meter diameter culvert is expensive and somewhat awkward to transport.

A conventional solid concrete pillar strikes me as likely quite expensive, and perhaps more difficult to assemble (due in significant part to the large reinforcing bar structure presumably required). It would also be far more difficult to disassemble. And my sense is that it would be far stronger than is necessary.

I remain fully open to any ideas however – any concept which addresses the need most efficiently will ultimately win my heart. I’m an electrical circuit design engineer, not a civil nor structural engineer. So this is generally outside of my skills. In general, I prefer thoughtful exploratory approaches which yield improved efficiency over an unimaginative default to conventional design. However, if a conventional design simply proves to be the best option, then it would win my heart.

I’d appreciate any thoughts or references you have, including the basics for the construction of the circular base pad.

Thanks so much and regards, Bruce Hillsboro, OR 97123-9074

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http://www.AirplaneHome.com (http://www.AirplaneHome.com/Images/22Sep2011ImagesCatalog.htm)

http://www.HikokiIe.com

#153 by jayson on March 4, 2012 - 12:08 am

hi

can you help me with our thesis? i’m 4th yr civil eng’g student

our thesis title is “proposed design of special foundation considering the effect of mine blasting-induced ground vibration”

we focus only on residential house foundation. what is the initial step we should do?

how to design foundation considering blast loading?

thank you for the response and this would be a helpful for our research.

#154 by regim raj on March 5, 2012 - 7:19 am

Dear Ben

I want plan to start my G+2 home. please tell me about details please. building size 42’x20′ 1. column size

2. no of rod 3. rod size

4. no of column (15 ok) please reply me…..

#155 by KOTLURI on March 7, 2012 - 1:40 am

HAI THIS IS VERY NICE SITE FOR CIVIL ENGINEERS

I AM NEW FOR THIS WHICH IS BEST SOFTWARE TO DESIGN FOOTING DESIGN

#156 by BenzuJK on March 8, 2012 - 11:24 pm

Staad Pro is being used for structural design purpose. But of course you need to be thorough with your structural design knowledge to use this software.

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#157 by vaibhav patil on March 7, 2012 - 10:15 pm

hi, i’am second year civil engg student and i want to know what are the foundation details that are to be taken into account while selecting the type of foundation to be decided for a skyscraper

#158 by zahir on March 8, 2012 - 4:46 am

hello, I would like to know is it acceptable practice to place an isolated footing in fill area ,I have 1.4 m fill over the existing ground level,or i have to embed it below the ground level

#159 by BenzuJK on March 8, 2012 - 11:07 pm

Hello Zahir,

You shouldn’t place your isolated footing in fill area. You should cent percent prefer embedding your footing below the ground level to maintain the integrity and stability of the structure. If don’t do they, the structure is bound to develop foundation problems in futures. The most common one in this case would be sinking foundation.

Be very careful while designing foundations. Remember that is the core of the structure. Let me tell you, foundation problems are disastrous and are very expensive to repair.

Have you hear of the saying,”Precaution is better than cure”. Follow it. That is what we engineers should be doing.

All the best!

Also check out my articles on Sinking foundation. They will give you an idea about what kind of problems they create.

Sinking Foundation – I Sinking Foundation – II

#160 by swapnil prabhu on December 11, 2012 - 1:13 am

hello ma’am,

all the information on the site and your explanation to all the difficulty for various questions have provided me more knowledge than any other source, thanks a lot for all the valuable information.

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Hello Swapnil,

We are glad to know that our articles have been helpful. We look forward to hearing from you often. Cheers

#162 by rakesh on March 11, 2012 - 8:48 am

Hey! could u tell me if length of pillars are unequal(underground portion), will it create any problem to the building…

#163 by malleswari on March 13, 2012 - 11:07 pm

khan :

what is the difference between one way shear and two way shear? thank you

hi benzu mam

I want to know , how to fix the depth of isolated footing? Which are the factors that influence the depth of footing? Is there any codes that specifies the isolated footing depths?

#164 by malleswari on March 13, 2012 - 11:10 pm

we want to know the depth fixation of isolated footings?

#165 by anshuman sharma on March 18, 2012 - 3:24 am

what we have to prefer structural steel columns or rcc columns?

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i want to design a singly reinforced T-beam by entering some data i.e. depth 300mm, width of beam -250mm, clear span-6.5mt, M-20, fe-415, bearing of simply support -250mm, please help me for solve me the problem and guide me.

#167 by reela on March 19, 2012 - 4:54 am

hello

my question is how many cement column need to build 80 meter square and for each column of cement how many bag of cement it need

thanks a lot

#168 by devang on March 20, 2012 - 3:57 am

how to find aggregate correction factor?

#169 by Ashly on March 20, 2012 - 8:45 am

Hello Benz,

I have a quick question on column footing. What happens if the column is not centered on the footing mesh? Does it compromise on the strength of the structure?

#170 by srinivas on March 20, 2012 - 10:38 pm

Hello Srinivas,

Firstly, you need a plinth beam to tie the isolated column because if you dont do so, it might result into bending of column resulting in collapse.

4′x4′ footing size is pretty small. Your column steel design is good. If the column c/c are not more than 12′ than you could go for G+3 without any hesitation.

Dear sir,

Thanks for your above given suggestion for my query on 8.6.11.

How can i tie the plinth beam, to the isolated coloumn. ( can i rise one more coloumn beside the isolated coloumn ).

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How much footing size required for three storied building. waiting for your valuable suggestion.

thanking you srinivas.

#171 by S Q Faridi on March 23, 2012 - 6:54 am

How & which combination shall be taken for foundation design in following given conditions : LOAD CASES REACTIONS (KN)

V H

Dead Load 16 6 Dead Seismic R 2 4 Dead Seismic L -2 -4 Live Load 53 23 Wind End Load -83 -21 Wind Left Load -84 -43 Wind Right Load -51 -7

#172 by shabier on March 24, 2012 - 10:51 am

how do i make contact with you in order for you to assist me in my drawings for foundations with consultation. I’m willing to hive a meeting with you to discuss my requirements. Thank you

#173 by Debal Chatterjee on March 26, 2012 - 3:56 am

Can you kindly provide the calculation for depth required to withstand punching shear

#174 by DAN AKPAN on March 26, 2012 - 9:17 am

Please, how many rod will be used to design a drainage of width 1m, height 1m and lenght 1m? I will be greatfull if you can assist me.

thanks. Dan.

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#175 by Shamsudheen on March 29, 2012 - 10:21 pm

Dear Sir,

My house construction is progressing in Kerala, Kochi. I would like to know whether I can use kota stone slabs or like that materials for my wardrobes partitions and racks instead of going for ferrocement slabs, mdf etc. If so with kota stone or then how would be the connection with the wardrobes walls to insert this slab? Thanks

Shamsudheen

#176 by Girish BM on April 1, 2012 - 4:56 am

Hi Benz

we are planning to built for industrial shed

span 25 mtr widht, centre height of shed willbe 35 ft . and crane capacity will be 10 ton. request to inform what willbe civil footing size

and column size for foundation ? Regards Girish BM +919552598092 india #177 by Bhuvan on April 1, 2012 - 6:14 am Hi,

I am planning for construction of 1st and 2nd floor on a building which is around 25 years old. Currently only the ground floor exists at this place. The current buliding has been laid out on foundation and not columns. As per my dad, the foundation is of 5 courses.

Please let me know whether it is safe to go in with additional 2 floors on this building. Also request to know how many courses of foundation is needed for a 3 storyed building.

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sir,

I design a three floor building column footing, 100cmx100cm size. 23cm rcc,then followed by 45cm to sloped. 10mm bar used for net. column size 23cmx35cm. this design is satisfied for the building.

#179 by pravin patil on April 2, 2012 - 7:54 am

dear madam,

how can i calculate size of columns, no. of columns for 15 x 50 plot. also i wanna know how much steel required for 3 floor building for the same area.

plz suggest me suitable floor height taking all consideration such as ventilation, conditioning of room.

#180 by Aman on April 2, 2012 - 11:02 pm

Sir,

Can you please tell me, on what basis the foundation is designed..? And which type of foundation should be used in different soil strata?

#181 by ramachandran on April 4, 2012 - 5:08 am

soil test depends to which type fondation need to building ho to understand kindly tel me for this answer

#182 by BenzuJK on April 8, 2012 - 4:08 am

Soil test is carried out by the Surveyors. If you are a Civil Engineer, your job is to hire a surveyor before you begin your structural design. The survey will tell you as to what kind of soil it is and how much is the bearing capacity of soil. Bearing capacity of soil will help you design the foundation of the structure.

Check out this article:

Guide to Structural Design of a Building

thank u

pile fountation about to article give madam

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Dear madam/sir,

I am constructing R.C.C. building for 2099 Sq.ft. plinth area . Foundation work completed . All column tied with tie beam on ground and it is completed upto slab level.

1) No of column= 19 nos. 2) Size of column= 12”*12” 3) Footing size = 4′ * 4′ 4) Dia of rod = 04 nos. of 16mm

5) Foundation is 1.2 m below ground level and .90 m plinth ht. above ground level. Also we have three nos. span of length 5.5 m from c/c of column.

Can i construct the building upto G+1 safely . Also can you suggest me as on thumb rule for beam size and the reinforcement dia and nos.

Check out this article. This will help answer many of your questions.

Minimum standards for Structural design

#186 by nick brown on April 5, 2012 - 5:35 pm

hi

my best wishes to u and many thanks to u for solving our problems after that must say that i am going to start a project of a business complex which would consist of 5 stories in the area of 520 sq meter, so i would like u to help me either by giving me a reference for civil engineering works or u may guide me to design and work on it, and must say that i am also a student of civil engineering and i live in noida up. and if u give me the refence around noida will be thankfull of u…

regards

Hello Nick,

We are launching a new business website where we would offer Architectural and Civil Engineering services at a minimum cost. I will get back to you only if you could wait for the next two weeks until we launch our website online.

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Cheers

#188 by Habibpk on April 5, 2012 - 9:57 pm

hi Benz,, Please can u advice me for the 23’span and 40′ long simply supported continuous slab without column support,two way slab need the how many concealed beams required with rebar detailand what will be distance c/c of re bars in both ways main/distribution.

Regards, hrbmorai

#189 by Larson on April 8, 2012 - 6:31 am

What is necessary for providing column starter at the Base of the Column.

#190 by Rasta on April 10, 2012 - 1:30 am

Hi

for column, how much does it contributes to each level of a building when you are calculating the seismic weight of a building???

for each level ive been tryn to calculate the weight which includes taking the weight(N) of the slab, beams, etc for each level and total them up to represent the weight of a particular level..but when it comes to columns im really not sure coz the column runs from the bottom to the uppermost of the building, so for each level how do we take the weight of the column???

#191 by Mohsin Sk on April 11, 2012 - 11:50 pm

Hi,

we are building RCC home on 1000sq fit area. I have got the construction layout and pillars design from professional. I am thinking of directly constructing slab over pillar without walls. but i have heard that slab will break if done in that fashion. What will you suggest? what should be the minimum slab requirement to avoid such incidence?

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can u tell me pile fountation depnds upon details design wait for u’r reply

#193 by DENIS V. Balatero on April 15, 2012 - 10:34 pm

Hi,good day, I need help.I am currently designing an extension of a church with 6 m. width and 11m long.it has a balcony design on top with the same size of the extension desired.Problem is,because of budget constraint i can’t make it to the soil test to know the soil bearing capacity.If in this case I wouldn’t know the design of its column and footing foundation.Can you please help me?Can you give a maximum design?… other problem is that I observe,when excavating i have notice that from the natural grade line and just excavated almost 2.00m,water is coming out.The proposed height of the front structural column is almost 10m,what will i do?can you please help me on this matter?I need it as soon as possible.Thanks and God Bless.

#194 by bliss on April 16, 2012 - 6:34 am

can u give me a research topic on building structural work?

#195 by sudhesh on April 17, 2012 - 10:45 am

Hi,

My best wishes for launching Architectural & civil engineering business at minimum cost , looking forward for the same at the earliest. please let me know your website details ……….

#196 by vinoth on April 19, 2012 - 10:11 am

Hi,

Kindly advice me about pile foundation, I’m going to build my own house 1100sq feet. In that area each builders are making difference pile foundations because of loose soil. E.g. –

1. Bottom of the single Column Dia – 0.75 feet

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No of the pile – 3 or 4 or 5 piles Depth – 15 feet

2. Bottom of the single Column Dia – 1feet

No of the pile – single pile Depth – 15 feet

Please advice me economic pile foundation methods Thanks

#197 by Bashar on April 27, 2012 - 1:24 am

Hi,

can u explain me … that how we can done 6 foot foundation for 34 foot height and 3 foot by 3 foot watch tower (6×75 Angle of tower), please explain with drawing if possible.

#198 by SAMEER on April 30, 2012 - 6:08 am

Is there any need to use steel reinforcement for wall like wall ties, mesh

For fixing marbles to the wall there is any necessaty to fix it by using steel angle & bolts

#199 by Afroza on May 1, 2012 - 6:42 am

Helo Benzu,

1) In a frame structure angle between RCC Column and beam laterally how much will be allowable Angle(?)? 2) If the angle between RCC beam and column is more than 90 degree;is it wise to raise the building vertically upto 2/3 story (where the foundation is 3storied)?

#200 by Afroza on May 1, 2012 - 6:55 am

BenzuJK : Hello Mr. Kuttan,

(50)

have regarding the construction field. Will try me best to help you whenever possible. Benzu

Like this site very much!!!

#201 by Chethan on May 2, 2012 - 12:54 am

Hi,

I’m constucting a gnd + 3 floor house on a 1200 sq ft plot. Right now as per plan from our engineer, we have about 12 columns, which are like 5 in a row on either ends and tow in the middle row. To be frant I really dont have much idea about the number of columns, load bearing capability, etc. My question is, are 12 columns sufficient for a 4 floor house on 30×40 sq ft. Secondly my engineer due to some vaasthu reason wants to live with just 10 columns, while getting rid of the 2 columns in the middle row. Is it something acceptable? My concern was that the two rows of columns are seperated by 23 ft. Is it ok to have it this way? Please advice.

#202 by A Beg on May 3, 2012 - 12:39 pm

want to discuss about a plan …but can’t copy/paste here.how can I attached the plan that I can solve some confusion about the plan.

Very helpful and informative your site is! Thank you.

#203 by Mohammed on May 5, 2012 - 5:32 am

hi,

plz, i want to know about portable houses

and what are the things required for foundation of portable houses.I want to know its sizes and dimension

#204 by BenzuJK on May 6, 2012 - 2:39 am

Hello Mohammed,

Check this out. This could be of help to you.

Transportable Homes

Foundation Design

Guide to Foundation Design | Column

Footings