No abstract

No abstract

No abstract

Nano silica is a fine convergent material of 10-9m size.  Due to its fineness, stiffness gets increased and cracks get reduced. As nano silica is fine, the mechanical strength will be increased and the durability will also be increased. Nano silica will reduce the pores compared to nominal concrete specimens. In this to study strength and durability behaviour of M70 high performance concrete with Nano Silica as admixture partially replacing cement by 0% 5% 10% 15% 20%. The experimental investigation of sorptivity test, alkalinity measurement test, water absorption test, totally 30 cubes and 15 cylinders specimens were casting and testing for strength and durability.  Specimens namely cubes, cylinders are cured for 28 days. In standard environment, after this curing period a test to analyze the strength and durability as carried out. The strength and durability start shown in increasing trend with increase in the quantity of nano silica. XRD, XRF Techniques are used to study the micro structure of the concrete. The nano silica addition reduces the pore amount and makes the concrete denser in micro structure level, which in turn increases the strength and durability.

No abstract

This paper involves the study made to investigare the effects of colloidal nano silica and their properties on concrete with a constant replacement of recycled aggregates at a level of 100%. Polypropylene fiber of 2% is added in all mixes to enhance tensile properties of concrete. In many cities there is a surge in construction and demolition wastes constitute the major portion of solid waste production in the world. The reuse of such wastes as a new construction material were used to reduce the huge amount of natural resources. Here, ordinary Portland cement is replaced by weight fraction of nano silica at replacement levels of 0%, 0.5%, 1%, 1.5%, and 2%. The colloidal nano silica act as a filler material which increase some of the mix properties, it also act as accelator to enhance pozzolonic action. The further presence of nano silica enhance the strength and properties of concrete up to 1.5% of replacement criteria, such as mechanical strength tests were conducted in concrete mixes. it has been concluded from scanning electron microscope (SEM) analysis that the denser matrix is formed at 1.5% of replacement of nano silica.

Effects on Flexural behavior attribute of nano SiO2 is a most widely used material in cement and concrete to boost the completion because of its pozzolonic reactivity moreover the pore stuffing effect. The results were obtained for mechanical strength, by assorted the reduced contents of 5%, 10%, 15% and 20% NS by volume fraction of cement. For further study, Finite Element Software ANSYS 10.0 is used for modeling and analysis by nonlinear steady flexural strength of the beam by two points loading.  The micro structure XRD, XRF diagnosing the migrate properties of high strength concrete, such as permeability and ion transports. Nano silica into concrete mix has shown result of increasing mechanical strength, and flexural behaviour of high strength nano silica concrete. The numerical modeling and experimental inspection circulate that the optimal reduced content of cement with ns is around 15 % of greatest strength increased.

It has become the agenda to use the bottom storey as the parking area in the multi-storey buildings and it has been quite a disturbance caused by RCC columns occupying more while projecting down to the ground. To get rid of this disturbance and for the aesthetic appearance, the number of columns in the bottom storey has to be reduced so that number of the footing will also get reduced. To achieve this, the five-storey RCC framed structure of plan area 30m X 33m which is assumed to be situated in Chennai with each storey height of 4m is modelled in STAAD Pro software in the way that the loads from the four columns present in the ends of each room will be transferring to the single-column placed in the centre of each room at the bottom storey. Then the necessary loads such as Gravity loads, Seismic loads, Wind loads, and software-generated automatic load combinations were applied to the generated model and the analysis was carried out. Similarly, the conventional model of the same plan was also analyzed by STAAD Pro software with the same set of load cases, and a comparative study of structural parameters such as bending moment, shear force, and deflection was done. Finally, both the models were designed as per IS code and Cost analysis between the two models was carried out.