考虑材料的拉压模量不同及应变软化特性的柱形孔扩张问题  

EXPANSION OF CYLINDRICAL CAVITIES IN STRAIN-SOFTENING MATERIAL WITH DIFFERENT ELASTIC MODULI IN TENSION AND COMPRESSION

作　　者：罗战友[1] 杨晓军[1] 龚晓南[1] 

机构地区：[1]浙江大学岩土工程研究所,浙江杭州310027

出　　处：《工程力学》2004年第2期40-45,共6页Engineering Mechanics

摘　　要：建立了拉压模量不同及应变软化特性材料的柱形孔扩张理论。对于岩土类材料,提出用a及b分别作为拉压模量不同和软化特征的控制参数,运用不同模量弹性理论及应力跌落软化模型推导了Tresca和Mohr-Coulomb材料柱形圆孔扩张问题的应力及位移解。分析了不同模量及软化特性材料对柱形孔扩张的影响,结果表明:圆孔极限扩张压力,塑性区的发展规律,应力场,位移场等均随着模量参数a和软化系数b的变化而变化,因此若采用经典的弹性理论及传统的不考虑应变软化来对岩土类的工程材料进行设计计算,必会带来较大的误差。An expansion theory of cylindrical cavities in strain-softening materials with different moduli in tension and compression is presented. For geotechnical materials, two controlling parameters α and β are introduced to take into account the different moduli and strain-softening properties. By means of different modulus elasticity and stress-softening model, general solutions calculating Tresca and Mohr-Coulomb materials' stress and displacement fields of expansion of cylindrical cavities are derived. For expansion of cylindrical cavities, the ultimate expansion pressure, stress and displacement fields and development of plastic zone are found to vary with the different elastic moduli and strain-softening properties. If classical elastic theory is adopted and strain-softening properties are neglected, rather large errors may be resulted in.

关 键 词：岩土工程 柱形孔扩张问题 Tresca材料 Mohr-Coulomb材料 不同模量弹性理论 应力跌落软化模型 

分 类 号：TU431[建筑科学—岩土工程] TU452[建筑科学—土工工程]