横观各向同性岩体边坡与预应力锚索框架梁相互作用研究

为研究横观各向同性岩体边坡与支护结构的相互作用机制,结合高速公路边坡工程,对现场岩样进行分组实验,通过不同层理面走向的岩样进行单轴压缩实验,确定边坡横观各向同性岩体的弹性特征参数.在横观各向同性岩体的应力-应变关系等理论基础上,建立横观各向同性岩体边坡与预应力锚索框架梁相互作用的分析模型,提出预应力锚索最佳锚固角的概念,利用有限元法进行数值分析,对各种横观各向同性岩体边坡的预应力锚索锚固角度以及横观同性岩体边坡与预应力锚索框架梁相互作用进行参数研究,提出层理的方向性对支护结构影响的规律.研究结果表明,所提出的分析模型和方法可为横观各向同性岩体边坡的预应力锚索框架梁支护设计提供了理论依据和工程借鉴.

INTERACTION BETWEEN TRANSVERSE ISOTROPY ROCK SLOPE AND PRESTRESSED ANCHOR CABLE WITH FRAME BEAM SUPPORT

The rock mass in natural state is a discontinuous anisotropy mass,therefore,if rock mass is still regarded as isotropy mass,it will not agree with the actual situation.In general analysis of engineering cases,anisotropy material includes orthotropy material and transverse isotropy material.In order to study the interaction between transverse isotropy rock mass and supporting structure,engineering geology of the slope at an expressway project is considered.Then,the laboratory tests for rock samples from field were carried out;and the uniaxial compression tests for rock samples with different stratification planes are performed to determine the indices of describing elasticity characteristics of transverse isotropic rock.Based on the theory of stress-strain relationship of transverse isotropy rock mass,the analytical model of interaction between rock mass transverse isotropy of slope and prestressed anchor cable with frame beam is established;and the notion of the optimum anchorage angle in prestressed anchor cable is presented.The interaction between rock mass transverse isotropy of slope and prestressed anchor cable with frame beam was analyzed with finite element analysis.At the same time,the study on parameters of the interaction between rock mass transverse isotropy of slope and prestressed anchor cable with frame beam and the optimum anchorage angle in prestressed anchor cable is performed.The rules of the influence on directivity of stratification plane of supporting structure are determined.The results show that some reasonable and reliable references and actual engineering experiences on the design of prestressed anchor cable with frame beam supporting for transverse isotropy rock slope can be accepted.