OPTIMAL DESIGN OF UNDER SLUICE GATE USING FEM -A CASE STUDY OF BHIMGODA BARRAGE

Abstract

Gates are essential hydro mechanical control equipment required for under sluice in the water resources projects. Several types of gates are developed, out of which fixed wheel vertical lift gate and radial gate are used in general. Without sacrificing the operation requirements like failure free performance, water tightness, rapidity in operational and convenience in installation and maintenance, it is desired that the cost of the gate should be minimum with lesser weight of gate and hoisting capacity. To achieve these goals, the design of various components of the gates is to be optimized. The numbers of horizontal girders control the skin plate thickness as well as section of vertical stiffeners and the numbers of wheels control the section of end vertical girder. Hence the quantity of steel for the vertical lift gate depends on all these factors for given water head. In this dissertation an attempt has made to analyze stress and displacements and carry out design optimization of vital parts using Finite Element Model through ANSYS software. A comparative study between conventional design results and FEM design results has been carried out to find out the effectiveness of conventional design procedure. A comparison between design results before optimization and after optimization has also been made. This study is limited to skin plate, Vertical stiffener, horizontal girder, vertical end girder and wheel of an existing Fixed Wheel Vertical Lift Gate Fitted in under Sluice of Bhimgoda Barrage. From the FEM analysis, it is established that the conventional design results of under sluice gate of Bhimgoda barrage quite safe but we should take care of top horizontal girder and Skin plate Panel-C (upper portion of second unit of gate). From optimization study of under sluice gate of Bhimgoda barrage, it is found that the optimal number of horizontal girders is 4 as against 3 girders actually presented. The total steel quantity decreases by 5.42% with 4 numbers of horizontal girders, as against 3 girders provided of the gate. Similarly the total steel quantity decreases by 4.52% with 8 numbers of wheels on each side, which is optimum number of wheels as against 6 wheels on each side of the gate.