Water Resources and Power

The rock-bolted crane beam is an important supporting structure in underground powerhouse,so the safety and stability is especially important.Based on the prototype observation,anchor bar stress,attachment of its two crane beams to the surrounding rock and the deformation status of surrounding rock were analyzed with safety monitoring at its excavation stage and the crane load.The stress characteristics and stability of the rock-bolted crane beam were evaluated.The results show that the large deformation and stress adjustment of rock mass caused by the excavation unloading of surrounding rock,the deformation of surrounding rock is large,the stress level of anchor bar is high.After the excavation is completed,the monitoring data tend to be stable.All the bolt stresses are below the yield strength of steel,and the maximum joint opening between the girders and their surrounding rock is 1.24 mm.During the load test,the increment of each observation data is not large.In general,the rock-bolted crane beam is safe and stable,and can meet the production and operation requirements.