基于现场承压板试验的岩体参数及修正方法

摘要：由于承压板下方的应力或变形不均匀性，使得不同部位变形计算的变性参数差异较大，采用中心点或边界点的变形量计算岩体变形参数的合理性尚未统一定论。根据刚性圆形承压板和柔性方形承压板在中心点和边界点的弹性模量解析解，论证承压板不同部位变形量计算的变形参数的差异性；采用三维有限元试验模拟研究不同承压板刚度条件下岩体变形量及变形参数，对比分析由中心点与边界点变形量计算的变形模量与真实参数之间的差异与规律。研究表明：岩体变形模量的计算值随承压板刚度增大而减小，且越接近于岩体的真实变形模量；刚性圆形承压板外边缘岩体表面位移较岩体表面平均位移小35%，柔性方形承压板角点岩体表面位移较岩体表面平均位移小42%；最后依据此研究结果对锦屏二级水电站隧洞区现场承压板试验结果进行修正，提高试验参数的合理性。

Deformation Parameters and Its Correction Method Based on In-situ Bearing Plate Test

Abstract: The rationality is yet unified conclusion by using the deformation of the center or the boundary points to calculate the rock deformation parameters. According to the modulus of elasticity analytical solution of rigid circular and flexible square bearing plates at center and boundary points, this paper demonstrated the difference of deformation parameters at different parts of bearing plate; by using three-dimensional finite element simulation, this paper studied rock deformation and deformation parameters of bearing plate in stiffness condition, and comparative analyzed the difference and laws of deformation modulus and real parameters of deformation calculations of center and boundary points. Studies show that: the calculated rock deformation modulus decrease with bearing plate stiffness increasing, and more and more close to the real deformation modulus of rock mass; the surface displacement of rock mass boundary is 35% less than average surface displacement of rigid circular bearing plate; the surface displacement of corner points is 42% less than average surface displacement; finally, based on the results of this study, the field test results of bearing plate in tunnel area of Jinping Hydropower Station are fixed to improve the rationality of test parameters.