Deep and large foundation pit deformation internal force physical simulation method

The invention provides a deep and large foundation pit deformation internal force physical simulation method. The method comprises the steps that a proper similarity ratio lambda is determined according to a deep and large foundation pit engineering design drawing and a construction special scheme; obtaining a model with a corresponding size and a corresponding supporting structural member material through the similarity ratio lambda; manufacturing the model according to the size of the model and the corresponding supporting structural member material; a distributed optical fiber monitoring sensing system with enough measurement precision is embedded into the manufactured model according to the requirements of a construction drawing; simulating excavation of the deep and large foundation pit according to a special construction scheme, and collecting data of the distributed optical fiber monitoring sensing system in the process; the collected data are sorted and analyzed, the whole physical simulation process