Experimental system, testing methods and strength evaluating technologies for geotechnical material under complex dynamic conditions in earthquake-prone mountainous area

An integrated large-scale triaxial dynamic geotechnical shear testing system, comprising a four-column loading frame (25), and further comprising:

• a shear box (17), a z-axis servo cylinder (11), an x-axis servo cylinder (19), a y-axis servo cylinder (23), and a specimen transport system, wherein the shear box (17) is arranged in the four-column loading frame (25), the z-axis servo cylinder (11) is arranged at the top of the four-column loading frame (25) and vertically acts on the shear box (17) through a z-axis press head (16), the x-axis servo cylinder (19) and the y-axis servo cylinder (23) are arranged on side walls of the four-column loading frame (25) and horizontally act on the shear box (17), one side of the four-column loading frame (25) is provided with an opening, the specimen transport system is arranged at the opening, the shear box (17) is transported into the four-column loading frame (25) through the specimen transport system, and the shear box (17) is a simple shear box (8) or a direct shear box (9);
• a hydraulic system (3) and a cooling system (4), wherein the hydraulic system (3) is configured to supply hydraulic oil to the z-axis servo cylinder (11), the x-axis servo cylinder (19), and the y-axis servo cylinder (23), and the cooling system (4) is configured to cool the hydraulic oil supplied by the hydraulic system (3);
• a data collection system, wherein the data collection system is configured to measure and collect loading parameters of the z-axis servo cylinder (11), the x-axis servo cylinder (19), and the y-axis servo cylinder (23);
• and
• a computer control system (2) and a computer control cabinet (1), wherein the computer control system (2) is electrically connected to the computer control cabinet (1), and the hydraulic system (3), the cooling system (4), and the data collection system are all electrically connected to the computer control system (2);
• wherein the direct shear box (9) comprises a base (21), a y-axis friction-reducing roller array (40), a shear press head (41), an x-axis reaction backing plate (45), an x-axis reaction backup nut (46), a y-axis reaction backup nut (48), a connection backup nut (49), a y-axis reaction backing plate (50), an upper direct shear box (53), and a lower direct shear box (55), wherein the lower direct shear box (55) is arranged on the base (21), the upper direct shear box (53) is arranged at the top of the lower direct shear box (55), the shear press head (41) is arranged at the top of the upper direct shear box (53), the y-axis friction-reducing roller array