Patent ID: 11913186
Assignee: CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC E  G | IPC E  G

Claim 16:
17. An in-situ test method for a subgrade dynamic resilient modulus, employing the in-situ test system for a subgrade dynamic resilient modulus according to claim 1, and comprising the following steps:
at step S1, selecting test points along a same straight line on a subgrade surface to be tested, and leveling the subgrade surface;
at step S2, trailing the test vehicle (5) to the leveled subgrade surface to be tested to enable the bearing plate (12) and the loading plate (22) to be in full contact with the subgrade surface, wherein the center of the bottom of the bearing plate (12) is located at a middle test point, the second high precision displacement sensor (34) and the first high precision displacement sensors (29) are mounted on corresponding test points respectively, and the bearing plate (12) and the loading plate (22) are at horizontal position and spaced apart; mounting an appropriate counterweight block (18) according to a dead weight load of a pavement structure layer, and adjusting the test vehicle (5) to be horizontal and stable;
at step S3, setting a loading waveform, a load size, a loading frequency and a number of loading times of a pre-applied vehicle load of the servo cylinder (9) through the computer (7);
at step S4, starting the servo cylinder (9) to apply a vehicle load under specified parameters, and transmitting resilient deformation displacement values of various test points to the computer (7) through the first high precision displacement sensors (29) and the second high precision displacement sensor (34); and
at step S5, performing, by the computer (7), inverse calculation for a dynamic resilient modulus value of a subgrade through a software according to the vehicle load applied by the servo cylinder (9) and the resilient deformation displacement values of various test points of the subgrade surface collected by the first high precision displacement sensor (29) and the second high precision displacement sensor (34).