The SMW construction-method pile foundation pit support project for a certain project in Yaoqiang, Jinan, has a foundation pit excavation depth of 11 meters and an overall support length of more than 150 meters. It falls within the scope of deep foundation pit construction and imposes extremely high requirements on the stability of the support structure and the tightness of water-stop and seepage-prevention measures.

     Compared with conventional projects, the on-site construction conditions of this project are extremely demanding, posing great challenges to construction progress. The construction site is very narrow, with an effective east-west span of less than 20 meters, barely enough to accommodate the entry and operation of construction equipment. This greatly compresses the construction operating space and places higher demands on equipment positioning, process sequencing, and on-site coordination.

     At the same time, the groundwater level in the project area is relatively high, and the risk of groundwater seepage is prominent. The ends of the mixing piles must fit tightly and seamlessly against the existing underground diaphragm wall in order to build a complete water-stop protection system and eliminate safety hazards such as foundation pit seepage and collapse, which greatly increases construction precision and connection difficulty.

     Limited by the inherent construction process of the triaxial mixer, the equipment cannot operate close to the wall, leaving a construction blank area of about 2 meters. If this blank area is not properly treated, it will form a weak zone in the water-stop system, directly damaging the overall foundation pit water-stop system and leaving serious seepage hazards for subsequent construction.

     Faced with these difficulties, the project department responded quickly and took proactive action. It immediately organized technical backbones to review the on-site working conditions and assess risk hazards, optimized the construction process based on rich deep foundation pit construction experience, and innovatively adopted high-pressure jet grouting drilling rigs to carry out supplementary pile construction in the 2-meter blank area, precisely filling the construction blind zone. While ensuring the water-stop reinforcement effect and thoroughly eliminating foundation pit seepage hazards, this maximized construction cost savings and achieved multiple benefits of improved quality, increased efficiency, and reduced costs. The project was ultimately accepted smoothly with no leakage.

      Craftsmanship is revealed in the details, and responsibility is demonstrated in overcoming difficulties. The smooth acceptance of this project fully demonstrates the project department's construction philosophy of striving for excellence and its pragmatic spirit of tackling difficulties head-on. Next, the project department will continue to uphold the work style of building quality with craftsmanship and achieving long-term success through practical work, strictly control construction details, strictly observe the safety bottom line, and strictly guard quality thresholds. It will go all out to advance subsequent construction tasks and support high-quality project construction with outstanding technical strength and excellent construction results.