铁路桥桥墩裂缝加固及效果评价  

Strengthening and Its Effect Evaluation of Pier of a Railway Bridge with Cracks

作　　者：刘天培[1] 

机构地区：[1]中铁第四勘察设计院集团有限公司桥梁处,湖北武汉430063

出　　处：《世界桥梁》2011年第6期70-74,共5页World Bridges

摘　　要：某铁路桥桥墩在施工完15d后开裂,裂缝多为竖向和水平环向裂缝,长1～6m、深210～905mm、宽0.1～0.23mm。为恢复裂缝处结构的整体性、受力性能及耐久性,采用先深层压浆,再对表面开槽并采用耐久性较好的加固型混凝土对深度超过钢筋保护层厚度的裂缝进行置换封闭。为研究加固后效果,采用通用有限元软件ANSYS建立桥墩未开裂模型、开裂模型和加固模型并进行计算。计算结果表明,裂缝对桥墩线刚度影响较小,各模型的墩顶水平总位移、应力和偏心均满足规范要求。加固后取芯检测结果表明,裂缝灌注饱满,浆液充分填充整条裂缝,混凝土芯样开裂面均不在裂缝灌注面,该方法修复效果良好。Cracks occurred in the pier of a railway bridge 15 d after construction of the pier.The cracks are mostly the vertical ones and the horizontal loop ones that are 1~6 m long,210~905 mm deep and 0.1~0.23 mm wide.To restore the integrity,mechanical behavior and durability of the structural parts of the pier around the cracks,the strengthening scheme of firstly grouting the cracks deeply,then grooving the surfaces of the cracks and finally replacing and closing the parts with crack depth greater than concrete cover thickness with high durability strengthening concrete was employed.To study the effect of the strengthening,the general finite element software ANSYS was used to set up and calculate the models of the pier without cracks,with cracks and after strengthening.The results of the calculation show that the influence of the cracks on the linear rigidity of the pier is little,the total horizontal displacement at the top of the pier and the stress and eccentricity of the pier of all models can satisfy the relevant requirements in the codes.The results of concrete core sample testing of the strengthened pier further show that the grouting of cement mortar into the cracks is to the full,the cement mortar completely fills in the whole length of the cracks,the cracks of the core samples do not occur in the grouting surfaces of the cracks and the effect of the strengthening and remedial of the pier with the cracks is quite sound.

关 键 词：铁路桥 桥墩 裂缝 加固 耐久性 评价 

分 类 号：U445.72[建筑科学—桥梁与隧道工程]