桩基事故处理技术探讨

通过列举西安绕城高速公路谢王互通式立交桥 B匝 19-2号桩基事故实例, 阐述了桩基事故处理的工艺过程: 钻孔取心确定缺陷部位, 分析事故原因; 高压水预清洗孔底粉尘和弱软层; 并应用超声波检测技术记录缺陷附近处理前的有关数据; 采用高压旋喷工艺加固缺陷部位; 再次应用超声波检测技术检测, 并与处理前相比较, 评价处理效果。还探讨了静压注浆、旋喷注浆、化学注浆 (高强粘结剂) 、加筋灌注、预应力锚索和旋喷注浆外围加固等技术在处理桩基事故中的应用条件, 提出了改进措施, 同时指出了还存在的一些问题。

Treatment technology of pile base accident

A case history study on the B za 19-2 pile base accident of the Xiewang Grade-Crossing-Elimination Bridge of highway surrounding Xi′an shows the technologic process of accident treatment,including bore drilling for determining the defect section;bottom-hole cleaning and recording related data near defect section with ultrasonic inspection;reinforcing defect section using high pressure rotary jet grouting;comparing and evaluating the treatment effect,determining with ultrasonic inspection.It is also discussed that the application conditions of static pressure grouting,rotary jet grouting;chemical grouting with strength-producing cementing material,grouting of reinfored steel,grouting of pretensioned cable anchor and the periphery reinforcing with rotary jet grouting.In the end some existing problem are presented.