Geotechnical engineering construction supporting structure for deep foundation pit excavation and installation method

The invention relates to the technical field of foundation pit supporting, in particular to a geotechnical engineering construction supporting structure for deep foundation pit excavation and an installation method.The geotechnical engineering construction supporting structure comprises two supporting plates and a plurality of supporting assemblies, the two supporting plates are arranged on the opposite side walls of a foundation pit respectively, and the two ends of the supporting assemblies abut against the two supporting plates to provide supporting force for the supporting plates. The supporting plate is formed by splicing a plurality of standard plates and a completion plate. The standard plate and the auxiliary standard plate are in standardized sizes, mass production is facilitated, production cost is reduced, when water is accumulated in the foundation pit, a water pumping pipe is inserted into a water pumping groove, the bottom end of the water pumping pipe can extend into a water pumping cavity alon