Elevated water tanks are the structures of greater importance which are considered as the main lifeline elements. Many displeasing experiences have taken place earlier due to the damage and collapse of elevated water tanks due to the occurrence of earthquakes. The reason behind the damage is lack of providing proper supporting system to the water tank to withstand the dynamic loads and also due to improper selection of staging. The main objective of the present study is to evaluate the seismic response of elevated rectangular water tank with different staging patterns and different water level conditions (full, half and empty). Four types of bracing systems of elevated water tank such as normal bracing, diagonal bracing, V bracing, and cross bracing are considered for the analysis with various water level conditions. A total of 12 combinations were analysed and base shear, base moment and roof displacement for the fixed models were calculated with SAP2000 v 20.0.0 software using Response Spectrum Method (RSM) and results are presented.

High-rise buildings are comparatively flexible with a low damping value having greater possibilities of failure and less serviceable. Failure potential can be minimized by counteracting vibrations. Methods are available to reduce the vibration of the tall buildings. One of the methods is control of vibrations using Tuned Mass Damper. The behaviour of tall buildings is analysed by considering specific time history data along with gravity loads. The structural mass required to resist the lateral loads increase exceedingly as the level of the building goes up if the stiffness of the building is not sufficient to resist the lateral forces. The main aim of the structural engineer is to provide a suitable solution for the effects due to gravity and lateral loads, by proper usage of Lateral Load Resisting System, approximate analysis and preliminary design. In the present study, the analysis of a 25 storey structure has been done to obtain an optimum mass ratio by using passive resistance. Then by using the optimum mass ratio obtained from the analysis of 25 storey structure, the analysis of 35 and 45-stories reinforced concrete tall buildings subjected to seismic loads has been done as per the IS codes of practice. Safety of the structure has been checked against allowable limits prescribed for joint displacements, base shear, interstorey drifts by implementing Tuned Mass Dampers (TMD). The behaviour of the building for an optimum mass ratio of Tuned Mass Damper with an increase in the height of building is found out.

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An earthquake is a natural phenomenon. Depending upon the intensity, itmay cause damageto life and property. Engineering community is striving hard to innovate different methods that can provide a solution to minimize this damage. The idea of seismic response control of the structures by using TMD's is considered for this study. A tuned mass damper (TMD) is a device consisting of a mass, a spring, and a damper that is attached to a structure in order to reduce the dynamic response of the structure. The frequency of the damper is tuned to a particular structural frequency so that when that frequency is excited, the damper will resonate out of phase with the structural motion. Energy is dissipated by the damper inertia force acting on the structure. Water tanks are integral part of all buildings and they impart large dead load on the structure. This additional mass can be utilized as TMD to absorb the extra energy imparted on the structure during earthquakes.The main objective of this project is to find the response reduction of structures subjected to various earthquake data's using different mass ratios. Analysis is carried for 5 storied and 10 storied buildings with and without water tanksand for different mass ratios varying from 5% to 25%.Water tank is placed at center and extreme corners of the building and columns of the tank with varying heights i.e., 1m, 2m, 3m and 3.5m are considered. 3 types of earthquake data (El Centro, N.Palm and Uttarkashi) are used for this study. Time history analysis is performed using SAP software. Results showed that tuning the parameters of water tank, it can be used as passive TMD to reduce the seismic response. Majority of the cases proved that results are appreciable when water tank is placed at center of the building, for columns of 3m height and 20% mass ratio.

Concrete is the most extensively used construction material in the world, which consumes natural resources like lime, aggregates and water. The worldwide production of cement has greatly increased, due to this production environmental pollution increases with emission of CO2 gas. To reduce this effect cement was replaced by some supplementary materials like Metakaolin, Fly ash, Bottom Ash, Ground Granulated Blast Furnace Slag (GGBS) and Rice Husk etc.. In this content Metakaolin was a pozzolanic material used in wide range in replacement of cement. Metakaolin is dehydroxylated aluminum silicate, due to its pozzolanic activity the strength properties and durability properties of concrete increases and reduction in Porosity and Permeability also. Now-a-day's availability of natural sand is constraint, so alternative material called ROBO Sand (having similar properties as that Natural Sand) is used in place of Natural sand to study the fresh and hardened properties of concrete. In this present investigation cement is replaced partially with metakaolin in varying percentage i.e. 0%, 6%, 12%, 18% and 24% and natural sand with 45% ROBO sand to get the different concrete mixes. The fresh and mechanical properties of concrete i.e. workability (slump test) and compressive strength, split tensile strength and flexural strength at 7 days, 28 days and 56 days are studied of the different concrete mixes and results are compared with conventional concrete.