关键词: 胶凝砂砾石;胶凝材料用量;应力-应变关系;本构模型;二元并联模型;

Abstract: Cement sand gravel material is a kind of poor cementing material for dam construction, and its stress and strain characteristics are different from that of conventional concrete. Traditional concrete’s constitutive model cannot be used for calculation of cement sand gravel material. Through analysis on stress-strain curve characteristics of cement sand gravel materials under different confining pressures, we found that the amount of cementing material had a significant influence on its constitutive model. Therefore, we generalized the rockfill body that characterized the initial formation state of cemented sand gravel material as rockfill component, and generalized the cementation of cementing materials as cement component. Based on the binary parallel conceptual model, empirical coefficients were introduced to investigate the influence of different amounts of cementing materials on the stress-strain relationship of the materials. A constitutive model of cement sand gravel material was established, and the constitutive model was verified by large-scale triaxial tests data. The model calculation results had good fitting relation with the experimental data, indicating that the model could well describe the nonlinear characteristics of stress-strain curve of cemented sand gravel material under different amounts of cementitious materials.

Key words: cement sand and gravel; amount of cementing material; stress-strain relation; constitutive model; binary parallel conceptual model