Underground diaphragm wall construction method under low clearance condition

The invention discloses a low-clearance-condition underground diaphragm wall construction method, and relates to the technical field of diaphragm wall construction. The construction method comprises the steps of construction preparation, survey setting-out, guide wall construction, slurry preparation and the like. Through the overall design, the safety performance is high, the stability of the pile foundation is improved by pre-burying the sleeve valve pipes around the viaduct pile foundation for grouting reinforcement, smooth construction of the underground continuous wall is facilitated, economic benefits are excellent, pier settlement is effectively controlled, the labor cost of treatment is saved, the input cost of engineering materials is reduced, and the construction period is shortened. The construction method has the advantages that smooth construction of the underground diaphragm wall on site is guaranteed, the application range is wide, the construction method can be adopted in urban subway undergro