With the background of mine layered filling,based on the initial ultrasonic velocity and dissipation energy evolution characteristics for three-layer composite structural backfills,and with Logistic model,a damage variable equation that could describe the complete damage process under the coupling effect of the interlayer structure and loading was established.Further,a segmented constitutive model of the structural backfill was constructed using damage mechanics and effective medium theories.The results reveal that the deformation damage characteristics of the structural backfill can be divided into three stages,i.e.initial cumulative damage,rapid damage and accelerated damage,and the location of the turning point of damage acceleration is related to the mechanical properties of the middle layer.The damage variable shows S-shaped growth,the initial damage is exponentially related to the c/t ratio and h/H ratio of the middle layer,and the maximum damage rate decreases with the decrease of the middle layer strength.The established constitutive model is able to describe the stress-strain process better,and has a high degree of consistency with the actual measured data.
关键词
结构充填体/能量演化/损伤变量/能耗特征/本构模型
Key words
structural backfill/energy evolution/damage variable/energy dissipation characteristics/constitutive model
维普
万方数据