A Review of Soil Constitutive Model Research: From Classical Theories to Frontier Advances

Soil constitutive models are mathematical expressions that describe the stress-strain-strength-time relationships of soil mass, and are essential for accurately predicting the deformation behavior of soil under external loading. This paper systematically reviews the development history of soil constitutive models both domestically and internationally. Internationally, the Cambridge model proposed by Roscoe et al. in 1963 marked the beginning of the modern stage of soil mechanics. Domestically, the concept of constitutive models began to appear in the 1970s, and with the development of computer technology and the finite element method, research on such models has gradually gained practical significance. On this basis, this paper introduces various types of constitutive model advances, including the BBM model for unsaturated soils, and typical recent achievements: a mechanical model for frost heave of trapezoidal canals based on the two-parameter elastic foundation beam theory, a three-dimensional modified Cam-clay model for structured soils considering intermediate principal stress, a modified Yin Zongze model for biopolymer-improved expansive soil, and a nonlinear dynamic constitutive model for soils considering fluid-solid coupling effects and its implementation in FLAC3D. Finally, future directions for constitutive model development are discussed, emphasizing the integration of physical mechanisms, mathematical methods, and computer technology to improve model accuracy and applicability in practical engineering. This paper serves as a theoretical reference for research in soil mechanics.