Study on stress-strain constitutive relationship of super-long-age plastic concrete under triaxial compression

Abstract

The triaxial stress-strain relationship of super long-aged (540d) plastic concrete mixed with clay and bentonite has been studied. According to the test, the stress-strain curves of plastic concrete under different confining pressures are obtained. It is found that the stress-strain curves under the lateral confining pressure are the same (0.4 MPa, 0.6 MPa), (0.4 MPa, 0.8 MPa), and the slope of the rising section is basically the same. Compared with the peak pressure ratio (0.2 MPa, 0.4 MPa), the lateral confining pressure is larger. In addition, the calculation formula of the peak secant elastic modulus and the triaxial compressive stress-strain relationship in accordance with the lateral pressure of plastic concrete have also been proposed. The fourth-order polynomial mathematical model. The establishment of the mathematical model provides a basis for the development of plastic concrete specifications and triaxial compression performance numerical analysis, and further promotes the engineering application of plastic concrete.