Mechanical Test and Constitutive Analysis of Internal Compression of Concrete

In order to accurately measure the stress-strain relationship inside concrete under compression，resistance strain gauges are suggested to be placed on acrylic resin rods to measure the internal strain of concrete specimens. A large-scale micro earth pressure cell is developed to measure internal stress in concrete. Embedding the relevant testing equipment inside the concrete test specimen，the uniaxial compression test of the concrete is carried out，and the accurate stress-strain relationship data inside the concrete is obtained. The results indicate that the internal constitutive model of concrete has good ductility compared to traditional constitutive models，and the internal peak strength is much higher than traditional constitutive models. Combined with several representative concrete constitutive equations，the test is simulated by finite element method，and the stress-strain curve，peak strength and peak strain are compared and analyzed. The results show that the measured internal stress-strain curve of concrete is reasonable and accurate，and the relevant measurement methods have good accuracy and feasibility. The finite element simulation results based on Chinese design model are in good agreement with the experimental results，which can be further popularized. © 2024 Nanjing University of Aeronautics an Astronautics. All rights reserved.