E₅₀ values of size.

Rock can undergo shape deformation and damage due to the influence of joint fissures, and the range of damage caused by joints at different rock bridge angles varies. To study the influence of rock bridge angle on the size effect of rock secant modulus, this paper adopts the principle of regression analysis and combines numerical simulation to carry out relevant research. The research results indicate that: (1) As the rock bridge angle increases, the secant modulus gradually decreases, following a power function relationship. (2) As the rock size increases, the secant modulus shows a trend of first decreasing and then stabilizing, following a power function relationship. (3) As the rock bridge angle increases, the characteristic tangent modulus and characteristic size gradually decrease, following a power function relationship. On this basis, we obtained their relationship formulas separately.岩体受节理裂隙影响会发生形态变形与损伤，且不同岩桥角度下节理造成的损伤范围存在差异。为探究岩桥角度对岩体割线模量（secant modulus）尺寸效应的影响，本文采用回归分析原理并结合数值模拟开展相关研究。研究结果表明：(1) 随着岩桥角度增大，割线模量逐渐降低，二者服从幂函数关系；(2) 随着岩体尺寸增大，割线模量呈现先降低后趋于稳定的趋势，且服从幂函数关系；(3) 随着岩桥角度增大，特征切线模量与特征尺寸均逐渐降低，二者同样服从幂函数关系。在此基础上，本文分别推导得到了它们的关系式。