Background: A steel frame system becomes structurally less efficient when subjected to large lateral loads such as a strong wind, earthquake. Many research efforts have been made to develop more efficient structural systems with better resistance against strong lateral loads. Methods: An attempt is made in this direction by both analytical and experimental studies. A bare steel framed model of size 4m x4m is chosen for G+2 storey with columns of height 4m. The particular frame is scaled down to 1:11 scale to perform shake table test for seismic zone-V in terms of modal frequencies. Same frame is modelled in Hypermesh software & analysis is done in Nastran and ETABS software's. The results obtained can be applied to 16 X 16m G+9 Multi-storeyed commercial complex structure and analysed in ETABS software for Base shear, response spectrum and pushover analysis to assess the performance of the structure. Findings: Prototype of G+2 storey scaled down model, ETABS and Nastran analysed models showed approximately same values of modal frequencies 10-12% which is an allowable percentage. Novelty: The results obtained shows that the base shear, performance point of the structural system and in terms of model frequencies are with in safer limits. The overall performance of the structure was found to be safe between operational to collapse stage. Advantages: The present work gives the dynamic behavior of bare steel frame subjected to lateral loads which helps in assessing the damage causing due to earthquake can be pretended to prevent the loss of life.

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Background: When a severe earthquake ground motion hits the structure even if it doesn't collapse it may undergoes inelastic deformations. Steel structure infilled with precast panels becomes less efficient when subjected to large lateral loads like strong wind and earthquake. Hence assessment of actual performance of steel frames provided with infills in the event of earthquake is essential. Methods: In the current study, a prototype model of steel frame size 4m x4m bay & 4m height with G+2 story is scaled down and subjected to lateral seismic load by conducting shake table test to assess modal frequencies, the same structure is modelled in Hypermesh and analyzed in Nastran, ETABS software. The results obtained are validated for a 16X16m bay of 4m height commercial complex of G+9 Multi-storeyed structure infilled with Ferrocement Precast panels analysed in ETABS software for base shear, response spectrum and pushover analysis to assess the performance of the structure. Findings: The frequency from modal analysis was found to be 45.21 Hz, for G+2 storied model in ETABS, values obtained for frequency, base shear, performance point of the structure are in appreciable. Novelty: As per the traditional earthquake design methods, structures are designed for less forces than maximum considered for earthquake. The overall performance of the structure is found to be safe even infilled with Ferrocement precast panels. Advantages: Ferrocement panels as infills has benefit as they are slender from structural point of view. Compared with steel bare frame dynamic behavior of bare steel frame which is infilled with Ferrocement precast panel subjected to lateral loads is high that helps in assessing the damage in the event of an earthquake in critical zone V.

In the present study, to demonstrate use of combined isotopic and salinity mapping in understanding local scale groundwater-surface water conditions the water samples were collected from 4 nos. of defined lakes (Kadaba, Belavatta, Pura and Nittur); groundwater samples were collected from shallow hand pumps/tube wells along the periphery of the lakes. The rain samples were also collected. The lake water appears to get enriched in its isotopic composition mainly due to evaporation in this region. Lake water salinities are lower compared to nearby groundwater salinity. The flow of groundwater, recharged at Nittur lake, continues to its downstream at least till Pura. Increase in salinity of groundwater is seen between the points Pura-groundwater & surface water (may be due to dissolution of sub-surface soil). The groundwater sampled at Belavatta is found to be recharged from local precipitation and not from surface body. The water body (Kadaba) is getting filled mainly due to precipitation and to some extent due to runoff from the upper reach of water body. There is a strong link between lake water–groundwater (e.g. site Pura) and groundwater–lake water (e.g. Site Kadaba). Therefore, this procedure is expected to radically increase the accountability of usage and help in planning of suitable ground water supply and would provide a holistic approach to promote maximum agricultural output and industrial growth.