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INTERNATIONAL JOURNAL OF PURE AND

APPLIED RESEARCH IN ENGINEERING AND

TECHNOLOGY

A PATH FOR HORIZING YOUR INNOVATIVE WORK

BEHAVIOUR OF FERROCEMENT PANELS UNDER DROP WEIGHT LOADING

DHANASHRI S. PIMPARKAR1, PROF. D. G. GAIDHANKAR2

1. Asst. Prof. Manav School of Engineering & Technology, Akola.

2. Asst. Prof. Dr. D. Y. Patil College of Engg, Akurdi, Pune.

Accepted Date: 12/03/2016; Published Date: 02/04/2016

Abstract: Ferrocement is a term commonly used to describe a steel and mortar composite material. Essentially a form of reinforced concrete, it exhibits behavior so different from conventional reinforced concrete in performance, strength, and potential application that it must be classed as a completely separate material. It differs from conventional reinforced concrete in that its reinforcement consists of closely spaced, multiple layers of steel mesh completely filled with cement mortar. This study aims to investigate the energy absorption of ferrocement panels reinforced with welded square mesh and woven mesh. Few panels were also tested by adding steel fibers in addition to mesh. For this a drop weight impact test is carried out on the 28 days cured ferrocement panels with and without steel fibers. Galvanized welded and woven square wire mesh with square opening was used as reinforcement. Crimped steel fiber was added in proportion of 1% by weight of panel with water cement ratio of 0.39.Permaplast ps-34 as an admixture added in mortar mix. The impact test was conducted under drop impact testing machine.

Keywords: Wire mesh welded & woven, Crimped steel fiber, Admixture, Drop weight impact test.

.

Corresponding Author: MS. DHANASHRI S. PIMPARKAR

Co Author: PROF. D. G. GAIDHANKAR

Access Online On:

www.ijpret.com

How to Cite This Article:

Dhanashri S. Pimparkar, IJPRET, 2016; Volume 4 (8): 450-463

PAPER-QR CODE

SPECIAL ISSUE FOR

NATIONAL LEVEL CONFERENCE

"RENEWABLE ENERGY

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INTRODUCTION

Ferrocement are used as retrofitting material since 19th century, after that it is developed as a wonderful construction material. Basic information regarding ferrocement, types of ferrocement, concept, applications of ferrocement, advantages and limitations of ferrocement and research work already done on ferrocement is described in this chapter.A large number of civil infrastructures around the world are in a state of serious deterioration today due to carbonation, chloride attack, etc. Moreover many civil structures are no longer considered safe due to increase load specifications in the design codes or due to overloading or due to under design of existing structures or due to lack of quality control. In order to maintain efficient serviceability, older structures must be repaired or strengthened so that they meet the same requirements demanded of the structures built today and in future. Ferrocement over the years have gained respect in terms of its superior performance & versatility. Ferrocement is a type of thin wall reinforced concrete commonly constructed cement mortar with closely spaced layers of continuous and relatively small size wire mesh. In its role as thin reinforced concrete product and as laminated cement based composite, ferrocement has found itself in numerous application both in new structure and repair and rehabilitation of existing buildings. Compared with the conventional reinforced concrete, reinforcement in ferrocement in two directions. Due to this two direction reinforcement it has homogeneous-isotopic properties in two directions. Benefiting from its usually high reinforcement ratio, ferrocement generally has a high tensile strength and modulus of rupture. It is a very durable, cheap and versatile material.

LITERATURE REVIEW

1 K. Mounika, A. Suchith Reddy, G. Latha[1] This paper deals with the study of impact resistance

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flexural strength and decreases the central deflection tendancy of specimens as compared to those without steel fibers due to increase in bond strength. There was a nominal amount of increase in impact energy absorption capacity of welded mesh reinforced specimen when the layers were increased from 1 to 2 layers. But, when small amount of steel fibers were added in small quantities (0.5% to 2%) the ultimate energy absorption of cementitious composites has increased as the steel fibers role is to act as crack arrestors. In all the impact test specimens, the damage is found to be loacalized i.e., at the point of impact load, the failure is characterized by formation of cracks initially at the bottom surface of the specimen, propogation to the top surface and then widening further.

2. G. Murali, A. S. Santhi and Mohan Ganesh[2] This study aims to investigate the impact

resistance of fibre reinforced concrete, incorporated with steel fibres at various dosages. For this, a drop weight test was performed on the 28 days cured plain and fibre reinforced concrete samples as per the testing procedure. Crimped and hooked end steel fiber of length 50mm with an aspect ratio equal to 50 was added to concrete in different proportions i.e. 0%, 0.5%, 1.0%, 1.5% with water cement ratio of 0.42. From the test results, it was proved that the FRC was effective under the impact loads thus improving the impact resistance. Also, the reduction of strength under impact load in each specimen for every 3 blows was determined by ultrasonic pulse velocity test. The addition of steel fibers to concrete can significantly improves their compressive strength when compared with plain concrete. The impact energy at failure was increased by 80%, 160% and 260% in case of crimped steel fiber and it was increased by 100%, 200% and 280% in hooked end steel when compared plain concrete. Also the impact energy of concrete is increased in both the cases ie, hooked end FRC and crimped FRC when compared to PC and this increase in energy is slightly greater in case of hooked end fiber reinforced concrete when compared to crimped fiber reinforced concrete.

MATERIALS AND METHODOLOGY

1) Cement- For casting the ferrocement specimens, Ordinary Portland Cement of 43 grade was used.

2) Sand- Well graded and washed river sand passing 2.36mm IS sieve was used in ferrocement. Locally available, clean, well dried and natural river sand was used throughout the investigation.

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4) Reinforcing Meshes- The reinforcement used for casting the specimens were galvanized square weld mesh and woven square wire mesh with 1.6 mm diameter and 20mmx20mm size opening.

Fig.1 Welded mesh used Fig.2 Woven mesh used

5) Steel Fibers- Crimped steel fiber is used in this study. The role of fibers is essential to arrest advancing of crack by applying pinching forces at the crack tips, thus delaying their propagation across the matrix and creating a slow crack propagation stage.

Fig.3 crimped steel fiber

6) Admixture- PERMA PLAST 34 was used in this study.

7) Preparation of Mould- The mould has been prepared by using flat wooden plates and from hollow square pipe of mild steel. For impact resistance test specimen, dimensions are:

i) 250mm x 250mm x 20mm

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Fig 4 Moulds for impact test specimens

8) Mix Design- Mix proportion was selected in such a way to get a workable and homogeneous mortar. The proportion of cement: sand is 1:1.5 and water cement ratio is 0.39 and 1.5% of admixture was considered.

9) Mixing of materials- Cement mortar is prepared by mixing cement and sand in dry state and then adding required amount of water in it and mixing them thoroughly. The procedure of mixing plays an important role for obtaining the strength and workability.Measure required amount of cement and dry sand. Then spread the measure amount of dry sand on the water tight platform. Spread the cement over the sand. Then mix it properly. After dry mix, a solution of water and admixture were added gradually to the mix. Mix the whole mass thoroughly for 5 to 10 min by means of shovel until the homogeneous mortar mix was obtained.

10) Casting of Specimens- The contact surfaces of the mould were oiled before casting for easy removal of specimen. A thin layer of mortar is laid in moulds with proper compaction. Then first layer of mesh was placed and mortar was applied with proper compaction. After placing the mesh, continued pouring the mortar to the top level of the mould and smoothened afterwards.

11) Casting of Specimens-

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12) Curing of Casted Specimens-The test specimens were demoulded after 24 hrs of casting and cured under normal conditions for 28 days.

IV.EXPERIMENTAL PROGRAMME

1) Impact Test-In drop weight impact testing, a mass is raised to a known height and released, impacting the specimen. The test set up was so adjusted, such that the metallic ball exactly at the center of the specimens and it was also ensured that the four edges of the specimens were freely supported. For each plate, the numbers of blows recorded for the appearance of the first crack, the failure crack were noted and then calculated impact energy initial crack load and ultimate load.

Fig.6 Impact Test Apparatus

RESULTS AND DISCUSSIONS

The total energy absorbed by the Ferrocement panels when struck by a hard impactor depends on the local energy absorbed both in contact zone and by the impactor.

The energy absorption can be obtained by using the formula- E = N x g x h x m

m=mass of drop weight,

N= number of blows,

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Where, E= impact energy, m=mass of drop weight,

N= number of blows, h = height of drop

1) FERROCEMENT PANELS USING WELDED MESH

i] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x20 2 68.67 183.12

3 91.56 263.23

Fig.7 Tested sample of 250mm x250mm x 20mm with 2 & 3 layers

ii] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x30 2 91.55 274.68

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Fig.8 Tested sample of 250mm x250mm x 30mm with 2 & 3 layers

2) FERROCEMENT PANELS USING WOVEN MESH

Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x20 2 103 228.89

3 114.45 274.67

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ii] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x30 2 114.45 286.12

3 148.78 412.02

Fig.10 Tested sample of 250mm x250mm x 30mm with 2 & 3 layers

3) FERROCEMENT PANELS USING WELDED MESH & STEEL FIBERS

i] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x20 2 80.11 217.45

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Fig.11 Tested sample of 250mm x250mm x 20mm with 2 & 3 layers

ii] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x30 2 171.67 331.90

3 206.00 423.46

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4) FERROCEMENT PANELS USING WOVEN MESH & STEEL FIBERS

i] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x20 2 171.67 297.57

3 183.11 343.34

Fig.13 Tested sample of 250mm x250mm x 20mm with 2 & 3 layers

ii] Average value of energy absorption capacity of ferrocement panels with 2 & 3 layers of mesh

Size of panel

(mm)

Number of layers Average Initial Energy

Absorption Capacity

(J)

Average Ultimate

Energy Absorption

Capacity (J)

250x250x30 2 137.33 354.79

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Fig.14 Tested sample of 250mm x250mm x 30mm with 2 & 3 layers

DISCUSSIONS

1) FERROCEMENT PANELS USING WELDED MESH

a. In 20 mm thick square panel having welded mesh, the energy absorption capacity increased by 40.8%, when number of layers increased from 2 to 3.

b. The energy absorption capacity of specimen increased by 45.8% in 30mm thick welded square panel when mesh layer increased from 2 to 3 layers.

2) FERROCEMENT PANELS USING WOVEN MESH

a. In 20 mm thick square panel having welded mesh, the energy absorption capacity increased by 19.99% when number of layers increased from 2 to 3.

b. The energy absorption capacity of specimen increased by 44.01% in 30mm thick welded square panel when mesh layer increased from 2 to 3 layers.

3) FERROCEMENT PANELS USING WELDED MESH & STEEL FIBERS

A. In 20 mm thick square panel having welded mesh, the energy absorption capacity increased by 47.38% when number of layers increased from 2 to 3.

b. The energy absorption capacity of specimen increased by 27.58% in 30mm thick welded square panel when mesh layer increased from 2 to 3 layers.

4) FERROCEMENT PANELS USING WOVEN MESH & STEEL FIBERS

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b. The energy absorption capacity of specimen increased by 9.68% in 30mm thick welded square panel when mesh layer increased from 2 to 3 layers.

CONCLUSION

1. From the above studies it can be concluded that the steel reinforcing fibers are capable of increasing the strength and more importantly, the energy absorption capacity of panels.

2. The occurrence of first crack was delayed & better crack distribution is attained in the ferrocement composites due to existence of fibers which led to the higher stiffness of specimen.

3. There was a nominal amount of increase in impact energy absorption capacity of welded mesh reinforced specimen when the layers were increased from 1 to 2 layers & 2 to 3 layers. But, when small amount of steel fibers were added in small quantities, the ultimate energy absorption has increased as the steel fibers role is to act as crack arrestor.

4. Thickness of panels also plays an important role in initial and final absorption capacity. Energy absorption capacity is more when number of mesh layers increases as compared to the increase in thickness of ferrocement panels.

REFERENCES

1. G. Murali, Prithvi Elango Impact Resistance Of Hybrid Fibre-reinforced concrete Plates International Journal of Mecahnical, Civil, Automobile and Structural Engineering Vol. 1, Issue 1, ISSN: 2395-6755 April- 2015

2. K. Mounika, A. Suchith Reddy, G. Latha Experimental Investigation On Performnce Of Fibrous Ferrocement International Journal Of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 4, Issue 8, August 2015

3. G. Murali, A. S. Santhi, G. Mohan Ganesh Impact Resistance And Strength Reliability Of Fiber Reinforced Concrete Using Two Parameter Weibull Distribution Vol. 9, No. 4, ISSN 1819-6608, ARPN Journal Of Engineering & Applied Sciences April 2014

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Figure

Fig 4 Moulds for impact test specimens

References

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