Concrete is a mixture of cement (usually Portland cement) and stone aggregate .When mixed with a small amount of water, the cement hydrates lock the aggregate into its rigid structure. Waste product may be used as fibres as well as siliceous material which may reduce the environmental degradation and also lower the consumption of valuable resources such as cement, fine aggregate, course aggregate and artificial fibres.
The samples were prepared in accordance with the IS standard relevant to each test. Cubes, cylinders and prisms were casted by pouring mixed concrete into moulds. Demoulding of moulds was done after 24 hours of casting. The specimens were then kept for curing in curing tanks and they were tested after attaining age of 7,28,56,91 days for compressive strength , flexural strength and split tensile strength.
45 2.1.5 Course aggregate: Considering all the above aspects, blue granite crushed stone aggregate of 12 mm as maximum size and of typical particle shape “average and cubic” are used as the course aggregate for the present investigation. The aggregates are tested as per the procedure given in BIS: 2386- The bulk density of coarse aggregate 1690 kg/m2 and the specific gravity 2.78 and fineness modulus of coarse aggregate 6.43 . The properties of coarse aggregate is given in table .1
In the design of concrete mixes, the compressive strength of concrete is generally the main target since it usually represents an overall picture of quality of concrete.The compressive strength is the maximum load per unit area sustained by a concrete before failure under compression. Since the strength development of concrete depends on both temperature .it can be said the strength is a function of summation of product of time and temperature this summation is called maturity of concrete. The cube specimens cured as above are tested as per standard procedure after removal from the curing tank and allowed to a dry under shade. The cube specimens tested under microprocessor based compression testing machine of
247 The material which passes through BIS test sieve no. 480 is termed as fine aggregate. Usually natural sand is used as a fine aggregate, at places where natural sand is not available crushed stone is used as a fine aggregate. The sand used for the experimental work was locally procured and conformed to grading zone III.
This research focused on investigating the effects of recycled aggregates on the material properties of concrete and the structural performance of reinforced concrete beams. Two different sources of recycled aggregates, crushed red bricks and demolished concrete, collected from local construction and demolition wastes, were analysed. The pre-wetting method was applied to recycled coarse aggregates aiming to study its effects on concrete specimens. Experimental results assisted by regression analysis revealed that the pre-wetting method could minimize the negative effects caused by recycled aggregate itself on the concrete slump and compressive strength test results. Pre-wetting method was also found improving the dynamic modulus of elasticity for concrete specimens. Adding supplementary cementitious materials was not as effective as the pre-wetting method in enhancing concrete slump, Ultrasonic Pulse Velocity (UPV), strength, or dynamic modulus of elasticity. The reduction of concrete UPV and compressive strength caused by recycled aggregates were more significant in the early curing age. Flexural tests on reinforced concrete beams indicated that although adding recycled concrete aggregates did not significantly change the beam failure load, the ultimate deformation of reinforced concrete beams was reduced by displaying more brittle failure behavior. It was indicated that the failure mode of beam was changed from flexural to shear, inferring that shear capacity of beam with RCA was reduced. Future research directions were proposed focusing on the durability studies of concrete members containing recycled aggregates especially when the pre-wetting method was applied.
suitable for use in the production of High Performance Concrete (HPC) due to their relatively high absorption capacity, unstable properties and recycled aggregates of weaker strength . Not only the Fly ash but large quantity of Agriculture waste like rice husk ash, Sugar cane bagass is also produced. Currently 106 Million tonne of Fly ash produced from thermal power plant in India. , and 30 Million tonnes of rice husk agricultural waste per annum is a matter of great concern. Till now Fly ash is being used in bricks, road, embankments and concrete works etc. In United States each year Fly ash discharges more than 100 Million tones of demolished waste etc . The used of Fly ash in concrete gives encouraging result all over the world including India. The main purpose of the experimentalinvestigation into assessing the strength of different concretes by using partial replacement of cement with Fly ash (F.A), demolished waste (DW) and Polythen Fibre (P.F).
iii) To study and evaluate the strength properties of coconut shell based concrete building blocks viz: hollow and filled blocks with various options of shells orientations to understand its capability to be used as a filler/composite/reinforcement material.
The application of recycled aggregate has been initiated in construction projects in many European, American and Asian countries with relaxation of infrastructural lawsfor increase the use of recycled aggregates. India is the third largest coconut producing country in the world. Huge amount of waste is generated by coconut. The waste coconut shell may be used to replace conventional coarse aggregates. It may help to produce concrete economically and at the same time , will also help to reduce its disposal problem. In this study, coconut shell is used as light weight aggregate in concrete. The properties of split tensile strength and compressive strength with partial replacement of recycled aggregate and coconut shellaggregateconcrete are investigated.
ABSTRACT: Plastic is one of the major environmental concerns in our country now days. This article studies how to recycle the plastics as construction materials without affecting its strength and properties. In this study, the natural aggregate was replaced by recycled plastic aggregate and it was used in concrete. The main aim of the study is to investigate the strength & properties of concrete with addition of plastics in concrete.
ABSTRACT: The economy of the structure is affected by high cost of conventional construction material. With increasing concern over the excessive exploitation of natural aggregates, synthetic lightweightaggregate produced from environmental waste is a viable new source of structural aggregate material. The uses of structural grade lightweightconcrete reduce considerably the self-load of a structure and permit larger precast units to be handled. Recently in the environmental issues, restrictions of local and natural access or sources and disposal of waste material are gaining great importance. Today, it becomes more difficult to find a natural resource. Use of the waste materials not only helps in getting them utilized in cement, concrete and other construction materials, but also has numerous indirect benefits such as reduction in land fill cost, saving in energy, and protecting environment from possible pollution effect. It also helps in reducing the cost of concrete manufacturing. In the present work, coconut shell as partial replacement for coarse aggregate in concrete is studied. The concrete with ground coconut shell was found to be durable in terms of its resistance in water, acidic, alkaline and salty. Density of coconut shell is in the range of 550 - 650 kg/m3 and these are within the specified limits for lightweightaggregate. The characteristic properties of concrete such as compressive strength, flexural strength, impact resistance, bond strength & split tensile strength using the mix made by replacing coarse aggregate with crushed coconut shellaggregate were reviewed in the present work.
4. Md. Safiuddin et al investigated to use of poultry waste in concrete through the development of concrete incorporating eggshell powder (ESP). Different eggshell powder (ESP) concretes had developed by replacing 5-15% of ESP for cement. The results indicated that eggshell powder (ESP) can successfully be used as partial replacement of cement in concrete production. The data presented cover strength development and transport properties.
G. Murali et.al. concluded that the use of recycled aggregate weakens the quality of recycled aggregateconcrete and the compressive, flexure and split tensile strength of recycle aggregate is found to be less than the natural aggregate. Jitender Sharma et.al. described production of recycled concrete aggregates, properties of recycled aggregates, its comparison with the natural aggregates and various applications in the construction industry. Prabhat kumar et.al. reported the recycling of concreteaggregate has been accepted to preserve natural aggregate for other important use. RCA (Recycle concreteaggregate) follow 3R i.e. Reduce, Reuse, Recycle. This paper deals with the review of existing literature work for understanding thoroughly about RCA. Hardik Gandhi et.al. concluded in his study that up to 20% use of recycled aggregate gives better results for direct and indirect compressive strength, ultra-sonic pulse velocity and rebound number values. Sharif Yahia et.al. reported in his study that the concrete can be produced with acceptable strength and durability if high packing density is achieved. Jianzhuang Xiao  from china, observed different studies on mechanical properties, durability and structural performance and revealed that it is feasible to apply recycled aggregateconcrete as a structural material with proper design and construction.
Concrete is the most widely used construction material which has several desirable properties like high compressive strength, stiffness and durability under normal usual environmental factors. While at the same time concrete found to be brittle and weak in tension. It is well known that concrete is mixed with other material was applied for resistance purpose. Palmoil tree fiber is a composite material consisting of a mortar of ordinary Portland cement, and fine aggregate reinforced with alkali resistant glass fibers.
The tensile strength of concrete is one of the basic and important properties which greatly affect the extent and size of cracking in structures. Concrete de- velops cracks when tensile forces exceed its tensile strength. A tensile strength is a measure of the ability of material to resist a force that tends to pull it apart. It is expressed as the minimum tensile stress (force per unit area) needed to split the material apart. As portrayed in Figure 17 & Figure 18 the evolution of splitting tensile strength, the experimental results show a trend that resembles the com- pressive strength results. The Splitting tensile strength of lime treated PKS con- crete and SCBA concrete decreased as increased in percentage replacement while increased in curing age. This reduction can be attributed to poor compaction, increased surface area of the lime treated PKS, reduced bonding properties of SCBA in constituent materials in concrete as compared to the cement. This is in concordance with result reported by .
The designed concrete is subjected to various tests to estimate the strength and other properties of the casting concrete. The main aim of the project is to developed strength attained by the concrete at various testing days from curing. Proper casting and curing of concrete will increase the strength of the concrete. Each test carried out 3 samples for every mix ratio and tested at required curing time. Then the average values are used for these strength analyzing. The testing procedure is detailed below:
Another reason for this study is the suitability and effectiveness of PKS and POF which act as a construction material for concrete production. Based on the previous research, PKS is used as lightweightaggregate to build a one-storey building and a foot bridge which is being monitored for their structural behaviour . While for the POF, it is considered as natural fibre which can behave like reinforcement as well as improve the mechanical properties of concrete composite . Hence, this study more concentrates on the comparison of conventional concrete, PKS concrete and PKS concretecontaining with POF related with their workability, water absorption and strength as well as the performance of these two materials (PKS and POF) when subject to compressive and flexural strength test. In a nutshell, four series of concrete mix consists of 0%, 25%, 50% and 75% PKS is replaced by volume according to coarse aggregate content. Besides, the concrete is divided into two categories; PKS concrete mixed with and without POF. The use of 5cm length and 0.25% of the volume fraction of POF was conducted in this study.Formatting the title, authors and affiliations
Cube Moulds, Cylindrical mould and beam mould of were used. They were lubricated with engine oil in order to reduce friction and to enhance removal of cubes from the moulds. They were then filled with concrete in three layers and each layer was tamped 25 times. The moulds containing the cubes were left for 24 hours under a room temperature for the cubes to set before removing the mould. The cubes were removed after 24 hours and were taken to curing tank
materials more sustainable and convert it to a usable and reliable replacement for natural raw materials [2,3]. Using of the wastes for production of concrete is considered as a method to implement the waste management. Oilpalmshell (OPS) is the common agricultural waste which could be used in concrete as aggregate to produce lightweightaggregateconcrete. Advantages of the lightweightconcrete in concrete structures encourage design engineers to employ this type of material for their design optimization. Due to reduction of the concrete weight, structural elements could be designed economically which leads to a significant saving in the cost of the supporting structures and foundation. With lighter concrete, for equal overall structural weight, it is possible to construct taller building or longer spans. The higher degree of thermal insulation of lightweightconcrete also is considered as a remarkable advantage. The method for production of lightweightaggregateconcrete by using of the OPS was introduced for the first time in Malaysia by Salam and Abdullah . Several researchers have pointed out that conventional coarse aggregate can be replaced with OPS to produce structural grade of lightweightconcrete [5,6]. Previous studies demonstrated that lightweightconcrete by using of the OPS has satisfactory mechanical properties and durability performance. For oilpalmshellconcrete (OPSC), the compressive strength was reported in the range of 13-22 MPa. While with inclusion of cementitious materials and admixtures, compressive strength of 37 MPa has been obtained. Furthermore, lightweightconcretecontaining OPS and limestone powder, with compressive strength up to 48 MPa and density of about 1990 kg/m 3 has been reported [7-9].