层面处理对碾压混凝土剪切过程中裂缝扩展的影响  

Influence of Layer Treatment on Crack Propagation in Roller Compacted Concrete Shear Process

作　　者：李阳[1] 庄晓隆 李志龙 王璟 柴嘉启 LI Yang;ZHUANG Xiaolong;LI Zhilong;WANG Jing;CHAI Jiaqi(State Key Laboratory of Eco-Hydraulics in Northwest Arid Region,Xi’an University of Technology,Xi’an 710048,China;National Energy Group Xizang Electric Power Co.,Ltd.,Linzhi 860114,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,西安710048 [2]国家能源集团西藏电力有限公司,林芝860114

出　　处：《硅酸盐通报》2024年第12期4359-4369,共11页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(U23A20673)。

摘　　要：为研究碾压混凝土层面剪切过程中的裂缝扩展规律,本文针对不同层面处理的碾压混凝土开展抗剪强度试验,分析了不同试件的破坏形态和抗剪强度变化规律,同时运用数字图像相关技术观测碾压混凝土剪切过程中层面裂缝发展规律,并结合热重技术分析了层面水化程度对裂缝扩展的影响。结果表明:层面处理可以有效提高层面结合效果和抗剪强度,降低裂缝宽度和扩展速率,经过纳米SiO_(2)砂浆处理的碾压混凝土层面结合效果最佳,裂缝最大宽度和扩展速率分别降低至0.528 mm和1.412 mm/s;层面裂缝发展过程分为初始、萌生、扩展、贯通四个阶段;纳米SiO_(2)能够促进水泥水化,水化产物含量与最大裂缝扩展速率呈负相关关系,因此纳米SiO_(2)的加入可有效降低层面裂缝扩展速率。In order to study the law of crack propagation in roller compacted concrete layer shear process,this paper carried out shear strength tests on roller compacted concrete treated at different layers,and analyzed the failure modes and shear strength change law of different specimens.At the same time,digital image correlation technology was used to observe the development law of layer cracks in roller compacted concrete shear process,and the influence of hydration degree of layers on crack propagation was analyzed by thermogravimetric technology.The results show that the layer treatment can effectively improve the bonding effect and shear strength of layer,and reduce the crack width and propagation rate.The roller compacted concrete layer treated with nano-SiO_(2)mortar has the best bonding effect,and the maximum crack width and propagation rate are reduced to 0.528 mm and 1.412 mm/s,respectively.The development process of layer cracks is divided into four stages:initial,initiation,expansion and connection.Nano-SiO_(2)can promote the hydration of cement,and the content of hydration products is negatively correlated with maximum crack propagation rate.Therefore,the addition of nano-SiO_(2)can effectively reduce layer crack propagation rate.

关 键 词：碾压混凝土 层面裂缝 数字图像相关技术 剪切破坏 热重技术 层面处理 

分 类 号：TV431.9[水利工程—水工结构工程]