陆地超长永久性钢护筒施工技术

Construction Techniques for Super-Long Permanent Steel Casings

结合三门峡黄河大桥工程实例,着重介绍了填土基础永久性超长桩基钢护筒沉放时垂直度和中心偏差的控制措施。钢护筒采用固定坐地式导向架,分3节沉放,按接高的顺序沉放,不能下沉时启动振动锤,均下沉到了设计底标高。整个施工过程安全顺利,各项关键指标完全满足规范要求。

With the project of the Yellow River Bridge at Sanmenxia as a practical example, the measures for controlling the ver- ticality and central deviation of the permanent super long steel casings of the pile foundation when they are immersed are intro- duced in great detail in the paper. With the help of the stationary guide frame,the steel casing is divided into three sections and is immersed section by section in the order of the extended length. When it can not be immersed, the vibrating hammer will be started. All the sections should be immersed to the designed elevation. The whole construction process is accomplished smooth- ly,with all the key quotas fully up to the requirements of the technical specifications.