乌东德坝基岩体变形模量与波速相关性及应用

Correlation between Deformation Modulus and Wave Velocity of Wudongde Dam Foundation Rock Mass and Its Application

坝基岩体变形模量是拱坝设计最重要的参数之一,实际中由于受到资金、时间、尺寸效应等限制,承压板试验不可能大量开展,工程常采用岩体变形模量与波速之间的相关关系来估算坝基岩体变形模量以评价其工程地质特性是否满足建坝要求。在乌东德水电站坝基边坡开挖工程中,开展了钻孔变形模量和声波测试。乌东德坝基为典型层状岩体,左岸坝基及河床岩体测试孔方向与层面走向近平行,右岸坝基岩体测试方向与层面近垂直,分析表明坝基岩体中有明显充填特征层面对岩体变形模量值和声波值具有不对称影响。结合测试钻孔高清电视选择合理数据,建立了坝基岩体变形模量与单孔声波二者之间的相关关系。通过与坝基岩体的承压板试验成果对比验证,所建立的相关关系是符合实际地质条件的。将该方法应用于大坝坝基深部岩体变形参数估算及坝基表层松弛岩体灌浆处理效果评价工作中,证明是可行的有效方法。本文的研究成果为坝基岩体变形特征的评价提供科学依据,对高拱坝坝基工程勘测设计具有重要的理论和实践意义。

The deformation modulus of rock mass is a key parameter for dam design.In order to evaluate the geological feature of dam foundation rock mass,the relationship between the wave velocity and the deformation modulus is used to estimate the deformation modulus of rock mass because it is difficult to conduct many bearing plate tests due to the limitation of funds and time.Borehole deformation modulus test and acoustic test are carried out during the excavation of wudongde hydropower station.The dam foundation is typical layered rock mass,the direction of the test hole of the left and river bed dam foundation is nearly parallel to the direction of the bed plane,and the direction is nearly vertical to the bed plane.The analysis shows that bed plane has an asymmetrical influence on the deformation modulus and acoustic wave value.And then the relationship is established based on the comprehensive analysis of the dam foundation rock mass characteristics.The method is proved to be effective in the evaluation of the modulus of the rock mass with the comparison to the test results of bearing plate test with the similar rock mass.And it is applied to evaluate the deformation modulus of and the evaluation of the grouting treatment effect to the relaxation rock mass.In this paper,the result provides a scientific basis for the evaluation of dam foundation rock mass deformation characteristics,speeds up the construction progress and reduces the investment,it also provides theoretical and practical significance to the survey and design of arch dam project.