Study on Viscoelastic Constitutive Model of Bedded Dolomite Considering Poisson Effect

To explore the mechanical mechanism of the dilatation failure of bedded dolomite caused by unidirectional loads, the viscoelastic theory and Poisson phenomenon were considered under the action of active stress and passive stress. The viscoelastic constitutive considering Poisson phenomenon model (VECPM) was then verified using the viscoelastic constitutive model (VECM) and the mechanical property test (MPT). Although there were some minor differences in the results of the VECPM, VECM, and MPT, the variation law of the stress-time curves was basically the same, which verifies the feasibility and accuracy of the VECPM. When the stress value did not change with time, the maximum stress measurement result of the MPT was 58.75% smaller than that of the VECM and 14.11% smaller than that of the VECPM. Therefore, the VECPM is more consistent with the actual stress state of rock, and its calculation accuracy is higher. The VECPM of bedded dolomite can reflect the process of viscoelastic rock gradually hardening and dilating, which accords with the actual stress situation of rock.