Properties of concrete incorporating sand and cement with waste marble powder

Ashish, Deepankar K.,Verma, Surender K.,Kumar, Ravi,Sharma, Nitisha Techno-Press 2016 Advances in concrete construction Vol.4 No.2

Marble is a metamorphic rock used widely in construction which increases amount of marble powder obtained from it. Marble powder is a waste product obtained from marble during its processing. Marble waste is high in calcium oxide content which is cementing property but it creates many environmental hazards too if left in environment or in water. In this research, partial replacement of cement and sand by waste marble powder (WMP) has been investigated. Seven concrete mixtures were prepared for this investigation by partially replacing cement, sand with WMP at proportions of 0%, 10% and 15% by weight separately and in combined form. To determine compressive strength, flexural strength and split tensile strength of concrete made with waste marble powder, the samples at the curing ages of 7, 28 and 90 days was recorded. Different tests of durability were applied on samples like ultrasonic pulse wave test, absorption and sorptivity. For further investigation all the results were compared and noticed that WMP has shown good results and enhancing mechanical properties of concrete mix on partially replacing with sand and cement in set proportions. Moreover, it will solve the problem of environmental health hazard.

The effect of attack of chloride and sulphate on ground granulated blast furnace slag concrete

Ashish, Deepankar K.,Singh, Bhupinder,Verma, Surender K. Techno-Press 2016 Advances in concrete construction Vol.4 No.2

This concrete is one of the most versatile construction material widely used for almost a century now. It was considered to be very durable material and required a little or no maintenance since long time. The assumption is very true, except when it is subjected to highly aggressive environments. The deterioration of concrete structures day by day due to aggressive environment is compelling engineers to assess the loss in advance so that proper preventive measure can be taken to achieve required durability to concrete structures. The compounds present in cement concrete are attacked by many salt solutions and acids. These chemicals are encountered by almost all concrete structures. The present study has been undertaken to investigate the effect of attack of chlorides and sulphates with varying severity on compressive strength of ground granulated blast furnace slag (GGBFS) concrete after immersion in salt solution for 28 days. The results indicate that the durability of GGBFS concrete increases with the increase in percentage replacement of cement by GGBFS for 20% and then gradually decreases with increases in percentage of GGBFS with cement (as in the study for 40% and 60%). Also there is increase in strength of GGBFS concrete with increase in age. Thus the durability of concrete improves when GGBFS is added as partial replacement of cement. In this study the strength of GGBFS concrete is less affected by chemicals as compared to conventional concrete when exposed to aggressive environment.

Successive recycled coarse aggregate effect on mechanical behavior and microstructural characteristics of concrete

Deepankar K. Ashish,Preeti Saini 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.21 No.1

With the increase in industrialization and urbanization, growing demand has enhanced rate of new constructions and old demolitions. To avoid serious environmental impacts and hazards recycled concrete aggregates (RCA) is being adopted in all over the world. This paper investigates successive recycled coarse aggregates (SRCA) in which old concrete made with RCA in form of concrete cubes was used. The cubes were crushed to prepare new concrete using aggregates from crushing of old concrete, used as SRCA. The mechanical behavior of concrete was determined containing SRCA; the properties of SRCA were evaluated and then compared with natural aggregates (NA). Replacement of NA with SRCA in ratio upto 100% by weight was studied for workability, mechanical properties and microstructural analysis. It was observed that with the increase in replacement ratio workability and compressive strength decreased but in acceptable limits so SRCA can be used in low strength concretes rather than high strength concrete structures.

Performance of bricks and brick masonry prism made using coal fly ash and coal bottom ash

Verma, Surender K.,Ashish, Deepankar K.,Singh, Joginder Techno-Press 2016 Advances in concrete construction Vol.4 No.4

The major problem of a coal combustion-based power plant is that it creates large quantity of solid wastes. So, to achieve the gainful use of waste materials and to avoid other environmental problems, this study was undertaken. The quantity of coal ash by-products, particularly coal fly ash and coal bottom ash has been increasing from the coal power plants around the world. The other objective of this study was to explore the possibility of utilization of coal ash in the production of ash bricks. In 15 different mixes, Mix Designation M-1 to M-15, the varying percentages of lime and gypsum were used and sand was replaced with coal bottom ash. Further, it has been noticed that the water absorption and compressive strength of mix M-15 is 13.36% and 7.85 MPa which is better than the conventional bricks. The test results of this investigation show that the prism strength of coal ash masonry prisms was more than that of the conventional bricks.

Analysis of stress dispersion in bamboo reinforced wall panels under earthquake loading using finite element analysis

Gulshan Kumar,Deepankar K. Ashish 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.21 No.4

Present study is mainly concerned about the idea of innovative utilization of bamboo in modern construction. Owing to its compatible mechanical properties, a beneficial effect of its use in reinforced concrete (RC) frame infills has been observed. In this investigation, finite element analyses have been performed to examine the failure pattern and stress distribution pattern through the infills of a moment resisting RC frame. To validate the pragmatic use of bamboo reinforced components as infills, earthquake loading corresponding to Nepal earthquake had been considered. The analysis have revealed that introduction of bamboo in RC frames imparts more flexibility to the structure and hence may causes a ductile failure during high magnitude earthquakes like in Nepal. A more uniform stress distribution throughout the bamboo reinforced wall panels validates the practical feasibility of using bamboo reinforced concrete wall panels as a replacement of conventional brick masonry wall panels. A more detailed analysis of the results have shown the fact that stress concentration was more on the frame components in case of frame with brick masonry, contrary to the frame with bamboo reinforced concrete wall panels, in which, major stress dispersion was through wall panels leaving frame components subjected to smaller stresses. Thus an effective contribution of bamboo in dissipation of stresses generated during devastating seismic activity have been shown by these results which can be used to concrete the feasibility of using bamboo in modern construction.

Mechanical behavior of concrete comprising successively recycled concrete aggregates

Verma, Surender K.,Ashish, Deepankar K. Techno-Press 2017 Advances in concrete construction Vol.5 No.4

The concrete industry of developing countries like India consumes majority of natural resources. The increase in population has necessitated the construction of more and more structures. Further many structures have completed their life span or have undergone damages thus warranting the demolition of these structures. India produces approximately 23.75 million tons of recycled concrete aggregate (RCA) annually. The natural resources are depleting at a higher rate with the increasing demand of concrete industry. This difficulty can be reduced with the use of RCA in land fill and concrete manufacturing. Use of RCA can provide cost savings and better energy utilization. This paper presents mechanical behavior of concrete comprising successively recycled concrete aggregate. Mechanical properties of recycled concrete get affected with number of recycling. In mix design successive recycled concrete aggregate (SRCA) was used in place of natural aggregates (NA) with 100% replacement. The test results of the compressive, flexural strength and pulse velocity were obtained for 14 and 28 days of curing age which showed significant improvement in results.

Improving compressive strength of low calcium fly ash geopolymer concrete with alccofine

Jindal, Bharat Bhushan,Singhal, Dhirendra,Sharma, Sanjay K.,Ashish, Deepankar K.,Parveen, Parveen Techno-Press 2017 Advances in concrete construction Vol.5 No.1

Geopolymer concrete is environmentally friendly and could be considered as a construction material to promote the sustainable development. In this paper fly ash based geopolymer concretes with different percentages of alccofine were made by mixing sodium hydroxide and sodium silicate as an alkaline activator and cured at ambient as well as heat environment in an electric oven at $90^{\circ}C$. Effects of various parameters such as the percentage of alccofine, curing temperature, a period of curing, fly ash content, was studied on compressive strength as well as workability of geopolymer concrete. The study concludes that the presence of alccofine improves the properties of geopolymer concrete during a fresh and hardened state of concrete. Geopolymer concrete in the presence of alccofine can be used for the general purpose of concrete as required compressive strength can be achieved even at ambient temperature. The 28 days compressive strength of 73 MPa, when cured at 90-degree Celsius, confirmed that it is also very suitable for precast concrete components.