The Improved Beam of Mechanical Calculation of Pipe Roof Advance Pre-support
In order to prevent the collapse of the tunnel hole,control the deformation of the surrounding rock,en-sure the stability of the tunnel face and the construction safety,the real mechanical behavior of the pipe roof is cal-culated.Based on the supporting effect of loose rock and soil in front of the tunnel face,the deformation of the initial support and its lag effect,the calculation model and deflection calculation formula of the pipe roof beam are derived.The formula derived values,on-site measured values and numerical simulation values are compared and analyzed.The analysis results show that the calculated values of the derived new beam model are closer to the on-site measured values compared with the numerical simulation values,indicating that it has certain rationality.After considering vari-ous factors,it is believed that the effect of controlling rock deformation is best during the surrounding rock grouting with the 114 mm diameter of the steel pipe.The maximum deflection value of the steel pipe calculated by the derived new beam model is 11 mm,which meets the construction requirements and verifies the reliability of the new beam model.
国家科技期刊平台
NSTL
万方数据
维普
