基于粒子图像测速技术的纤维改性珊瑚泥面层龟裂模型试验研究  

Model test investigation of cracking in fiber-modified coral mud surface layer utilizing particle image velocimetry technology

作　　者：方华强 丁选明[1] 张灵芝 李一夫 王红 辛义文 彭宇 李铮 FANG Hua-qiang;DING Xuan-ming;ZHANG Ling-zhi;LI Yi-fu;WANG Hong;XIN Yi-wen;PENG Yu;LI Zheng(College of Civil Engineering,Chongqing University,Chongqing 400045,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong 999077,China;Chongqing City Construction Investment(Group)Co.,Ltd.,Chongqing 400023,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]香港理工大学土木及环境工程系,中国香港999077 [3]重庆市城市建设投资(集团)有限公司,重庆400023

出　　处：《岩土力学》2025年第2期368-380,共13页Rock and Soil Mechanics

基　　金：中央高校基本科研业务费(No.2022CDJQY-012);重庆市杰出青年科学基金(No.CSTB2022NSCQ-JQX0020)。

摘　　要：为了开发珊瑚泥的工程应用价值,采用粒子图像测速(particle image velocimetry,简称PIV)技术,进行了聚乙烯醇(polyvinylalcohol,简称PVA)纤维改性珊瑚泥面层模型龟裂试验研究。获得了珊瑚泥面层的位移场和速度场,从多物理场作用、能量耗散角度揭示了珊瑚泥面层龟裂及抑裂机制。探讨了多物理场与土体水分蒸发、收缩以及龟裂之间的相互作用机制,为龟裂动力学行为提供了新视角。结果表明:(1)珊瑚泥面层表面颗粒移动轨迹在重力场的影响下呈现为顺时针涡流形式的收缩方向。珊瑚泥面层土颗粒在裂隙位置处具有极大值速率,而且随着裂隙的萌生、发育到扩展稳定,土颗粒速率会经历加速阶段,到达峰值后转变为衰减阶段。(2)珊瑚泥内部分碳酸盐矿物成分会发生化学硬化、结晶以及胶凝,PVA纤维与珊瑚泥颗粒之间以及珊瑚泥颗粒与颗粒之间产生胶结作用,提升了珊瑚泥强度。当纤维掺量为0.5%时珊瑚泥性能最优,珊瑚泥表面几乎无裂隙出现。(3)珊瑚泥龟裂存在张拉破坏、剪切破坏以及拉剪混合破坏3种形式。(4)从多场作用、能量耗散角度,揭示了珊瑚泥面层龟裂及抑裂机制,提出了对多物理场与土体蒸发、收缩以及龟裂之间的相互作用的新见解。土体龟裂过程中的水分场、位移场、速度场和应力场相互作用,共同影响土体的裂隙形成和发展。这些相互作用形成了一个复杂的系统,影响着土体的稳定性和力学行为。To assess the engineering application potential of coral mud,a model test was conducted on cracking in the surface layers of polyvinyl alcohol(PVA)fiber-modified coral mud using particle image velocimetry(PIV)technology.The displacement and velocity fields of the coral mud surface layer were obtained,revealing the cracking and crack inhibition mechanisms from the perspective of multi-physical field interactions and energy dissipation.The interaction mechanisms between multi-physical fields and soil moisture evaporation,shrinkage,and cracking were discussed,providing a new perspective on crack dynamic behavior.The results indicate:(1)Under gravity,the trajectories of surface particle movement in the coral mud surface layer show a clockwise vortex-like contraction direction.Soil particles in the coral mud surface layer reach maximum velocity at crack locations.As cracks initiate,develop,and stabilize,particle velocity accelerates,peaks,and then decelerates.(2)Carbonate mineral components in the coral mud undergo chemical hardening,crystallization,and cementation.Cementation occurs between PVA fibers and coral mud particles and between coral mud particles,enhancing the strength of coral mud.Optimal performance occurs at a fiber content of 0.5%,with minimal cracks on the coral mud surface.(3)Coral mud cracking occurs in three forms:tensile failure,shear failure,and tensile-shear mixed failure.(4)From the perspective of multi-physical field interactions and energy dissipation,the mechanisms of cracking and crack inhibition in the coral mud surface layer are elucidated,offering new insights into the interaction between multi-physical fields and soil evaporation,shrinkage,and cracking are proposed.The interaction of moisture,displacement,velocity,and stress fields during soil cracking collectively influences the formation and development of soil cracks.These interactions form a complex system affecting soil stability and mechanical behavior.

关 键 词：珊瑚泥面层 纤维改性 粒子图像测速技术 收缩与龟裂 多物理场 抑裂机制 

分 类 号：TU441[建筑科学—岩土工程]