某地下厂房岩壁吊车梁设计及超挖缺陷加固处理OA

The surrounding rock of the underground powerhouse of a certain hydropower project is granite,and the crane girder is bolted on rock wall.During the construction stage,based on the layout of the powerhouse and the bridge crane load,the dimensions and rock bolts of the crane girder have been preliminary formulated,they meet the requirements of the specifications after calculation.Based on the calculation results,the con-struction drawing of the rock-bolted crane girder has been completed.After the excavation of the rock wall was completed,significant over-excavation was observed,and there were defects in the formation of the rock wall.Therefore,the rock-bolted crane girder was strengthened:the lower part of the crane girder was added with concrete supporting walls and rock bolts to meet the stability requirements of the crane girder,and a special section of the erecting bay was added with concrete walls at the full height from the bottom of the erecting bay to the crane girder to support the crane girder.