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A large number of civil structures were designed according to old seismic code that do not meet current safety standards. They may also suffer from ageing and deterioration induced by environmental factors such as corrosive agents and earthquakes. A methodology has been developed to assess the current state of existing structures using vibration-based structural health monitoring. This technique has attracted civil engineering community recently. Vibration-based, non-destructive damage identification uses changes in the dynamic characteristics of the structure to identify damage. Full or large-scale dynamic tests of structural specimens provide unique opportunities to evaluate and validate these methods under realistic conditions, i.e. with the same level of measurement noise, estimation uncertainty and modelling errors, which are observed as in situ conditions. In this paper, we have studied the behaviour of existing structures and the models casted in the lab. Experimental determination of the dynamic characteristics of the model of RCC building under different levels of damage has been used to develop correlation between damage in the models of RCC buildings with its known dynamic characteristics using artificial neural network models. [ABSTRACT FROM AUTHOR]

• Here an attempt is made to assess the environmental flow requirement using the hydraulic approach, wetted perimeter method. • The assessment is done for its sufficiency by comparing it to the currently maintained e-flow. • To validate the calculated minimal flow value for its sufficiency, GIS application has been employed. • The wetted perimeter results show that the environmental flow required is in the limit of the existing flow maintenance. • Geographical Information System results support the sufficiency of the flow maintained in the downstream side of the dam. The environmental flow requirement varies from project to project based on their location, need, and habitat. The Binwa hydropower project is in the Kangra district of the Himachal Pradesh and a small hydropower project of 6 MW capacity. Here an attempt is made to assess the environmental flow requirement using the hydraulic approach, wetted perimeter method, and compared with the currently maintained e-flow. It is one of the old and commonly used method of assessing the environmental flow based on the hydraulic characteristics such as the depth, width, and perimeter. The discharge is computed for each depth along with the profile and a graph is plotted to obtain the required environmental flow. The assessed minimum flow values are customarily validated using a habitat or holistic approach. Here, to validate the calculated minimal flow value for its sufficiency, the Geographical Information System application is employed as it calculates the vegetation and water indices. The average of the breakpoint discharge has been calculated as 0.7724 m3/s. The minimal flow maintained in the Binwa basin is 0.9 m3/s which is within the limit of the existing flow maintenance during the lean period. The Geographical Information System results support the sufficiency of the environmental flow maintained in the downstream side of the dam. The wetted perimeter helped in deriving the environmental flow while the Geographical Information System application assisted in evaluating the sufficiency spatially. [ABSTRACT FROM AUTHOR]

The present research work investigates the slope instability along NH-05 near Jhakri, Himachal Pradesh, India. Initially, field investigation has been conducted to study the slope morphometry and characteristics. The studied landslides trends along NW–SE direction with height 27.26 m from the road surface and at an angle of 63° vertically post failure. Parameters responsible for slope stability such as particle size distribution, Atterberg Limit and shear strength parameters were collected through direct shear plot using soil samples collected from field. The results reveal that the soil coarse to fine loamy with no surface vegetation long the landslide areas. The absence of vegetation exposes the soil for erosion during high monsoon rainfall. Based on the shear test results the value of c and Phi is 10.28 kPa and 18.8°. 2 D limit equilibrium model has been used using Rocscience software for slope stability assessment. LEM model reveals a safety factor value 0.43 which is less than the value considered for stale slopes. Re-enforced bench slope with soil nailing has been suggested as a suitable stabilization measure with a FOS value of 1.2 which reveals the slope can be stabilized with the mentioned approach. [ABSTRACT FROM AUTHOR]