湿热交替下粉砂质泥岩裂隙动态扩展及机制研究  

Dynamic fracture propagation and mechanism of silty mudstone under hydrothermal alternation

作　　者：曾铃 郭雨 高乾丰 罗锦涛 查焕奕 卞汉兵 ZENG Ling;GUO Yu;GAO Qianfeng;LUO Jintao;ZHA Huanyi;BIAN Hanbing(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;School of Traffic&Transportation Engineering,Changsha University of Science&Technology,Changsha,410114,China;Key Laboratory of Bridge Engineering Safety Control by Department of Education(Changsha University of Science&Technology)Changsha 410114,China;Hubei Provincial Communications Investment Group West Hubei Expressway Construction Management Co.Ltd.,Wuhan 430051,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]长沙理工大学交通运输工程学院,湖南长沙410114 [3]桥梁工程安全控制教育部重点实验室(长沙理工大学),湖南长沙410114 [4]湖北交投鄂西高速公路建设管理有限公司,湖北武汉430051

出　　处：《岩土工程学报》2025年第4期820-828,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(52078066,52078067,52378440);湖南省自然科学基金杰出青年基金项目(2023JJ10045);长沙市杰出创新青年培养计划(kq2305023);桥梁工程安全控制教育部重点实验室开放基金项目(15KB01);交通运输行业重点科技项目(2022-MS1-032)。

摘　　要：湿热交替作用下粉砂质泥岩裂隙扩展是导致其边坡崩塌破坏的重要原因。围绕粉砂质泥岩的裂隙扩展问题,开展湿热交替试验和巴西劈裂试验,分析全过程裂隙发育规律及湿化、受热过程裂隙发育的差异性,探究湿热交替、裂隙对抗拉强度的影响,结合耗散结构理论研究开裂机制。结果表明:粉砂质泥岩湿化时裂隙闭合、受热时裂隙张开,在湿热交替中裂隙发育表现出螺旋式的动态增长规律,受热过程裂隙发育程度均大于湿化过程,裂隙发育差异性系数λ从2.18逐步减小至1.43。湿热交替、裂隙倾角减小均会劣化粉砂质泥岩的抗拉强度,随交替次数增多劈裂过程能量吸收能力减弱,弹性能占比减小、耗散能占比增多。粉砂质泥岩裂隙扩展可看作耗散结构逐步形成的过程,在湿热交替过程中能量、物质交换方式不断变化,内部结构不断调整,达到临界状态后,系统突变裂隙萌生扩展。研究结果可为粉砂质泥岩边坡安全防护提供一定的理论参考。Fracture extension is the cause of collapse failure of silty mudstone slopes.For the fracture extension of silty mudstone,the hydrothermal alternation and Brazilian splitting tests are conducted to analyze the pattern of fracture development.The influences of hydrothermal alternation and fractures on tensile strength are explored,and the fracturing mechanism is studied in combination with the dissipative structure theory.The results reveal that the fracture development in silty mudstone follows a spiral dynamic growth pattern,with a greater degree of development observed during heating than during wetting.The difference coefficient of fracture development gradually decreases from 2.18 to 1.43.The hygrothermal alternation and decreasing fracture inclination degrade the tensile strength of silty mudstone.The energy absorption of the splitting process is weakened with an increasing number of alternations,resulting in a decreasing proportion of elastic energy and an increasing proportion of dissipated energy.The fracture propagation of silty mudstone is a process of gradual formation of dissipative structure.The internal structure is adjusted due to the change of energy and material exchange mode,and the system mutation leads to the formation of fractures.The findings from this study can provide theoretical references for ensuring the safe protection of mudstone slopes.

关 键 词：边坡工程 粉砂质泥岩 湿热交替 裂隙扩展 能量耗散 

分 类 号：TU45[建筑科学—岩土工程] U417[建筑科学—土工工程]