摘要
针对某大型调水工程的双向预应力混凝土立墙内出现劈裂问题,在分析立墙结构特点的基础上,采用冲击映像法对裂缝的平面分布、严重程度以及损坏区域所占比例等进行了详细检测和成因分析,并通过取芯检验和带预制缝的有限元法数值模拟,验证了检测结果和分析结论.成功获取的56个芯样显示,冲击映像法对内部裂缝分布范围的检测精度高,分辨率好,检测结果为立墙的修复提供了可靠的基础资料.现场检测和数值模拟显示,容纳预应力钢筋的波纹管注浆不密实,内部积水在冬季冻胀是引起混凝土内部劈裂的根本原因,为我国北方寒冷地区后张法预应力结构物波纹管注浆作业质量控制的重要性和注意事项提供了例证.
Splitting cracks were found in the two-directional pre-stressed concrete walls of a large scale di- version project in north China. Based on internal structural characteristics of the wall~ the impact imaging method （IIM） was applied for the detections of cracks distribution, seriousness and damage area ratio of the internal cracks and the damage cause analysis. The core test and numerical simulation by 3D FEM with prefabricated joints element were also adopted for verifications. The 56 drilled cores show that the IIM has high accuracy and resolutions on the internal crack distributions. This result provides reliable data for deci- sions-making of the wall repair strategies. Both field test results and numerical analysis show that the frost of the water inside the corrugated pipes that contain the pre-stressed tendon lead to the internal splitting cracks, due to the incompact grouting into the pipes. This accident shows the significance of the grouting quality control of the corrugated pipes inside the post-tensioned structures in cold regions in northern Chi-
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2015年第7期977-982,共6页
Journal of Shanghai Jiaotong University
基金
中国科学院战略性先导科技专项(B类)(XDB10030500)
中国水利水电科学研究院开放基金项目(IWHR-SKL-201304)资助
关键词
大型预应力混凝土立墙
裂缝检测
裂缝机制
冲击映像法
vertical wall of large scale pre-stressed concrete structure
crack detection
crack mechanism
impact imaging method
