Study on Brittleness Control Mechanism and Ratio Optimization of Rock Burst Similar Materials Modified by Vinyl Acetate-Vinyl Copolymer Rubber Powder Based on Orthogonal Test

本研究基于正交试验设计原理，采用浇筑成型工艺系统探讨了胶砂比(1:2~1:5)、水胶比(0.3~0.6)、醋酸乙烯酯–乙烯共聚胶粉掺量(0~15%)及水膏比(1:1~1:4)等多参数协同作用对相似材料力学特性的影响规律。通过多指标响应分析，成功研制出具有优化性能的低强度高脆性岩爆模型相似材料(抗压强度15.86 MPa、脆性指数Bd 0.22、冲击能量指数ACF 11.90)。研究表明，醋酸乙烯酯–乙烯共聚胶粉通过构建三维聚合物网络结构并调控孔隙分布特征，能够在降低材料强度的同时显著提升其脆性及冲击倾向性，这为构建符合深部岩体力学响应的物理模型提供了新型材料解决方案。Based on the principle of orthogonal experimental design, the effects of multiple parameters on the mechanical properties of similar materials, such as cement-sand ratio (1:2~1:5), water-binder ratio (0.3~0.6), the content of vinyl acetate-vinyl copolymer glue powder (0~15%) and water-paste ratio (1:1~1:4), were studied by using the casting process system. Through multi-index response analysis, a low-strength and high-brittleness rock-burst model similar material with optimized performance (compressive strength 15.86 MPa, brittleness index Bd 0.22, impact energy index ACF 11.90) was successfully developed. The results show that by constructing a three-dimensional polymer network structure and adjusting the pore distribution characteristics, vinyl acetate-vinyl copolymer rubber powder can significantly improve the brittleness and impact tendency of the material while reducing its strength, which provides a new material solution for the construction of a physical model that conforms to the mechanical response of deep rock mass.