Abstract

The field bearing plate method test is the most commonly used method to determine rock mass deformation parameters. Currently, due to the effect of the applied test stress, the difference between the rheological model curve and test curve can be significant, namely the model cannot reflect the effect of the applied stress. In this study, a seven-component viscoelastic combination model that considers the effects of stress is proposed. Based on the proposed viscoelastic combination model and viscoelastic theory, the viscoelastic analytical solutions for the bearing plate tests are derived. Then, the viscoelastic characteristics of rock mass aging deformation as well as the effect of viscoelastic parameters on rock mass aging deformation are discussed. After that, a flexible bearing plate test and a rigid bearing plate test are carried out respectively, based on which the optimal rheological models and corresponding parameters of the rock mass aging deformation are identified according to the optimisation inversion method. Results indicate that the proposed combination rheological model with two Kelvin bodies is more preferable then that with only one Kelvin body. The bearing plate tests and the model parameters identification manifest that the proposed viscoelastic combination model is effective and reasonable.

摘要

现场承压板法试验是确定岩体变形参数最常用的方法。目前，由于外加试验应力的影响，流变模型曲线与试验曲线之间的差异可能很大，即模型不能反映外加应力的影响。在这项研究中，提出了一种考虑应力影响的七分量粘弹性组合模型。基于所提出的粘弹性组合模型和粘弹性理论，推导了承载板试验的粘弹性解析解。然后，讨论了岩体老化变形的粘弹性特性以及粘弹性参数对岩体老化变形的影响。之后，分别进行了柔性承载板试验和刚性承载板试验，在此基础上根据优化反演方法确定了岩体老化变形的最优流变模型和相应参数。结果表明，所提出的具有两个开尔文体的组合流变模型比只有一个开尔文体更可取。承载板试验和模型参数辨识表明，所提出的粘弹性组合模型是有效和合理的。结果表明，所提出的具有两个开尔文体的组合流变模型比只有一个开尔文体更可取。承载板试验和模型参数辨识表明，所提出的粘弹性组合模型是有效和合理的。结果表明，所提出的具有两个开尔文体的组合流变模型比只有一个开尔文体更可取。承载板试验和模型参数辨识表明，所提出的粘弹性组合模型是有效和合理的。