On the afternoon of December 15, the first foundation pit excavation for the pipe-jacking crossing section from Zhenluo East Road to Zhongguan Road in the Zhenlian Shitangxia Project was successfully completed.
The Zhenlian Shitangxia Project involves four pipe-jacking tunnel crossings. The crossing working shafts all adopt the “open-cut sequential construction” method. Depending on site conditions, the foundation pit retaining structures use either “bored pile support, cement-soil mixing pile waterproof curtain, and triple-tube high-pressure jet grouting pile gap filling” or “diaphragm wall” retaining schemes. The excavation depth of the launch shaft for Working Shaft No. 21 is 14.03 m. The construction of such a large-diameter pipe-jacking and deep working shaft is the first of its kind in the company's long-distance pipeline construction history. The project department overcame unfavorable factors such as lack of construction experience, complex surrounding pipelines and buildings, high coordination difficulty, harsh geological conditions, land acquisition and crop compensation, and difficulties in highway approval policy processing, and proceeded with careful planning and active promotion.
The successful excavation of this working shaft foundation pit to the required depth marks a major construction milestone for the project and has accumulated experience for the excavation of the remaining working shafts.