巴拉水电站引水隧洞围岩变形参数研究OA

To accurately determine the surrounding rock deformation parameters of the extra-large cross-section headrace tunnel of the Bala Hydropower Project,ensure project safety,and optimize the design scheme,this study integrated multiple technical methods such as rock physical and mechanical property tests,in-situ rock mass deformation tests,and sonic wave tests,in combination with the specific geological conditions of the pro-ject area.Through systematic analysis of the test data,a quantitative relationship between the sonic wave ve-locity and deformation modulus of the rock mass was established,and then key parameters such as the deform-ation modulus and unit elastic resistance coefficient of different types of surrounding rocks were systematically determined.The research results show that:the poorer the quality of the surrounding rock,the larger the thickness of the loosened zone,and the sonic wave velocity and deformation modulus of the rock mass decrease significantly;the established sonic wave velocity-modulus relationship has a significant correlation(R=0.90),which verifies its reliability.This study finally proposes a set of recommended values for surrounding rock pa-rameters applicable to this project,providing a key scientific basis for the accurate evaluation of the surrounding rock stability of the headrace tunnel and the optimal design of the support structure,and has important refer-ence value for similar projects.