Study on construction method of the super-large diameter pipejacking which used the world's first segmentary pipe

Slurry pipe-jacking was firmly established as a special method for the non-disruptive construction of the underground pipelines of sewage systems. Basically the system involves the pushing or thrusting f a jacking machine through concrete pipes ahead of jacks. This method can be used for the lifeline ipe constructions up to about 1km in length and 15m in curvature radius. reviously, it was impossible to adopt this method up to 3,000mm in diameter due to prohibit the transportation of pipes up to 3,000mm in diameter from the production plants to sites against the apanese traffic rule. To solve this problem, a half split type pipe, which can be brought to a site, has irstly developed in the world and the construction method was considered. Cylindrical pipes were manufactured completely, after split pipes were combined one by one at the onstruction site. However, there were no case studies on this type of installation, using the split pipe method (4,040mm in outside diameter and 3,500mm in inner diameter). From these points of views, the jacking machine which can be adopted to this method was manufactured and the ground settlements were measured. This paper reports the construction which became the first case in Japan using the supersized pipe jacking method.