三轴剪切条件下水泥胶结砂声发射特征信息演化规律研究  

Evolution of acoustic emission characteristic of cemented sand subjected to triaxial compression tests

作　　者：刘昂 张尔康 林文丽 LIU Ang;ZHANG Erkang;LIN Weni(College of Transportation Engineering,Nanjing Tech University,Nanjing 211816,China;Nanjing Intelligent Geotechnical Engineering Technology Research Institute,Nanjing 211899,China;School of Transportation,Southeast University,Nanjing 211189,China)

机构地区：[1]南京工业大学交通运输工程学院,江苏南京211816 [2]南京智慧岩土工程技术研究院有限公司,江苏南京211899 [3]东南大学交通学院,江苏南京211189

出　　处：《中南大学学报（自然科学版）》2024年第2期618-627,共10页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(42102319);江苏省自然科学基金资助项目(BK20210259);中央高校基本科研业务费专项资金资助项目(2242022k30055)。

摘　　要：结合声发射(AE)传感装置开展考虑水泥掺入比、围压等条件的水泥胶结砂排水三轴试验。研究结果表明:水泥胶结砂的AE特征信息演化规律与应力-应变曲线具有较好的对应性;累计AE事件随水泥掺入比的增大而减小,这与水化物的增加抑制了砂颗粒间滑移密切相关;随围压增大,累计AE事件增大,同时促进了AE信号在介质中的传播和胶结的断裂;随着水泥掺入比增加、围压降低,水泥胶结砂破坏形态由鼓胀破坏逐渐向剪切带破坏过渡。A series of drained triaxial compression tests,incorporated with acoustic emission(AE)measurement system,were conducted on cemented sands with various cement mixing ratios under different confining stresses.The results show that the evolution of AE characteristic information of cement-bonded sand has a good correspondence with the stress-strain curve.The cumulative AE hits linearly decrease with the increase of cement mixing ratio,attributed to the restraining effect of the hydration products on micromechanical behaviors dominated by the frictional sliding of sand particles.While the cumulative AE events increase with the increase of confining stress,primarily due to the higher confining stress promoting the propagation of the AE signal in the medium and the fracture of the cementation.The failure pattern of cemented sand gradually shifts from bulging failure to shear band failure with the increased cement mixing ratio and decreased confining stress.

关 键 词：声发射 水泥胶结砂 水泥掺入比 三轴剪切 破坏模式 

分 类 号：TU411[建筑科学—岩土工程]