离子型稀土矿体的剪胀特性及其弹塑性本构模型的构建

Dilatancy behaviors and construction of elastoplastic constitutive model of ion-absorbed rare earth orebody

通过塑性功增量分析离子型稀土矿体的剪胀特性,并在修正剑桥模型剪胀方程的基础上,提出离子型稀土矿体的剪胀方程,从而构建出适用于离子型稀土矿体的弹塑性本构模型。结果表明:1)所构建新的剪胀方程能够较好地描述离子型稀土矿体的剪胀比和其应力比之间的关系;2)确定了模型在一般应力状态下的弹塑性刚度矩阵,证明其对离子型稀土矿体的室内三轴CD试验结果具有较好的拟合效果,并进一步通过室内等p三轴试验和减p三轴试验验证了模型的有效性。

The dilatancy behaviors of ion-absorbed rare earth ore body were analyzed by the increment of plastic deformation work.On the basis of the dilatancy equation of the modified Cambridge model,the dilatancy equation suitabled for ion-absorbed rare earth ore body was proposed,then a new elastoplastic constitutive model was proposed.The results show the main conclusions are as follows:1)The new dilatancy equation can well describe the relationship between dilatancy ratio and stress ratio of ion-absorbed rare earth ore body;2)The elastoplastic stiffness matrix of the model under the general stress state is deduced,the model has made considerable fitting results for the triaxial CD test results,and the triaxial constant p test and the triaxial decreased p test verify its effectiveness.