摘要
加筋土桥台柔性复合结构(简称GRS-IBS)作为加筋土的一种改进技术,可有效控制路—桥过渡段差异沉降,以减少“桥头跳车”现象的发生。但目前GRS-IBS结构多参照加筋土挡墙进行设计,由于二者承载特性存在差异,其设计方法有待完善。以山西省太行一号风景道K43+175处桥梁工程为例,借鉴相关规范和标准进行GRS-IBS结构设计,并采用FLAC^(3D)建立有限差分数值模型进行数值分析,分别对桥台变形、筋材和墙面板受力进行验算,以确保工程结构安全。结果表明:GRS-IBS结构设计除需进行结构内部和外部稳定性验算外,还需采用FHWA推荐的计算方法对结构承载力和筋材拉力进行验算;采用现浇混凝土墙面板的GRS-IBS结构能满足相关规范对路桥过渡段不均匀沉降控制的技术要求,但为保证工程结构安全,需对墙面板顶部进行局部加强设计;GRS-IBS结构墙面板最大拉应力位于桥台中部偏下位置,建议在现浇混凝土墙面板受拉侧配置一定数量的钢筋,以避免混凝土产生开裂破坏。
As an improved technique of reinforced soil,the geosynthetic reinforced soil-integrated bridge system(GRS-IBS)could reduce the differential settlement at the roadbed-bridge transition section so as to avoid“bridgehead bump”effectively.But at present,GRS-IBS structure is mostly designed with reference to reinforced earth retaining wall,and its design method needs to be improved on account of the difference in bearing characteristics between two structures.Considering this,based on a bridge in Taihang No.1 Tourism Road K43+175 in Shanxi Province, the GRS-IBS was designed referring to the relevant specifications, and aFinite difference numerical model in the same condition was also established by FLAC^(3D) to analyze theabutment deformation, the geogrid tensile force and the panel stress respectively to guarantee the safety ofengineering structure. The results show that not only the internal and external stability of GRS-IBS should bevalidated, but also the bearing capacity and the geogrid tensile force should be checked using the formularecommended by FHWA;the GRS-IBS structure with cast-in-place concrete panel could meet the requirementof relevant specifications for the differential settlement at the roadbed-bridge transition section, but the top of thepanel should be reinforced to ensure the safety of engineering structure;the maximum tensile stress of the panelwith GRS-IBS structure was located in its lower part, and the reinforcement was suggested on the tension sideto avoid concrete cracking.
作者
赵建斌
白晓红
郑俊杰
谢明星
ZHAO Jianbin;BAI Xiaohong;ZHENG Junjie;XIE Mingxing(College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,P.R.China;School of Civil Engineering,Wuhan University,Wuhan 430072,P.R.China)
出处
《土木与环境工程学报（中英文）》
CSCD
北大核心
2023年第4期1-9,共9页
Journal of Civil and Environmental Engineering
基金
国家自然科学基金(52008285、52178341)
山西交通控股集团有限公司科技项目(18-JKKJ-23)。
关键词
加筋土桥台
加筋土
设计方法
工作特性
数值分析
geosynthetic reinforced soil-integrated bridge system
reinforced soil
design method
operating characteristic
numerical analysis
