层间强度对三维打印混凝土裂纹扩展的影响  

The Effect Interlayer Strengths on Crack Propagation in 3D Printed Concrete

作　　者：张庆贺 陈晨[2] 方致远 ZHANG Qinghe;CHEN Chen;FANG Zhiyuan(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan Anhui 232001,China;School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan Anhui 232001,China)

机构地区：[1]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,安徽淮南232001 [2]安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《安徽理工大学学报（自然科学版）》2022年第2期59-65,共7页Journal of Anhui University of Science and Technology:Natural Science

基　　金：国家重点研发计划基金资助项目(2019YFC1904304)。

摘　　要：为了探究不同层理面强度下3D打印混凝土的破坏过程及其对裂纹扩展情况,利用ABAQUS有限元分析软件,采用全局嵌入零厚度的cohesive单元的方法,研究在三点弯曲条件下层理面强度对3D打印混凝土裂纹扩展的影响。研究结果表明:层理面的存在影响了裂纹的扩展方向及过程。当层理面强度越弱时,会在层理面处出先起裂,产生沿层理面方向的横向裂纹,横向裂纹扩展会抑制纵向应力的传播,导致预制裂纹的尖端出现应力集中。由于裂纹不仅需要沿纵向延伸,还需要沿着层理面方向延伸,因此层间粘结越薄弱,所需要的荷载也越大。裂纹穿过层理面的穿层破裂主要是拉张破坏,沿层理面的顺层破坏为拉剪混合型破坏。层理面的存在会让裂纹断续延伸呈现不规则的扩展,揭示了层理面强度对裂纹扩展过程的影响。In order to investigate the damage process of 3D printed concrete under different bedding surface strengths and its effect on the crack propagation,the effect of the strength of the bedding surface on the crack propagation of 3D printed concrete under the condition of three-point bending was studied with the ABAQUS finite element analysis software and the method of globally embedding cohesive elements with zero thickness.The results showed that the existence of bedding surface affected the direction and process of crack propagation.When the strength of the bedding surface was weak,the cracking started at the bedding surface and the transverse cracks produced along the direction of the bedding surface,then the transverse cracks propagation inhibited the propagation of longitudinal stress,resulting in stress concentration at the tip of the precast crack.Since the crack needed to extend along not only the longitudinal direction but also the direction of the bedding surface,the weaker the inter-layer bond,the greater the required load.The cracks passing through the bedding plane were mainly tensile failures,and the bedding failures along the bedding planes were tension-shear mixed failures.The existence of the bedding surface would cause the intermittent and irregular extension of the crack,revealing the influence of the strength of the bedding surface on the crack propagation process.

关 键 词：3D打印混凝土 数值模拟 三点弯曲梁 层理面强度 破裂类型 

分 类 号：TU528.01[建筑科学—建筑技术科学]