岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2013年
z1期
2764-2771
,共8页
岩石力学%地基承载力%临界滑动场%Hoek-Brown非线性破坏准则
巖石力學%地基承載力%臨界滑動場%Hoek-Brown非線性破壞準則
암석역학%지기승재력%림계활동장%Hoek-Brown비선성파배준칙
rock mechanics%bearing capacity of foundation%critical slip fields%Hoek-Brown nonlinear failure criterion
针对节理岩体非线性破坏特征,发展基于 Hoek-Brown 破坏准则的临界滑动场理论进行节理岩体地基承载力的计算.首先将Hoek-Brown准则的剪切强度逐点等效到Mohr-Coulomb强度线上,求得每点的瞬时内摩擦角和瞬时黏聚力;在此基础上,改进基于Mohr-Coulomb准则的临界滑动场理论,建立新的迭代算法,将Hoek-Brown强度准则与临界滑动场理论结合起来,求解被动土压力和地基承载力.同时,综合分析GSI和mi值对地基承载力的影响.算例对比分析结果表明,该方法能迅速准确地确定节理岩体地基最危险破坏滑面并得到相应的地基极限承载力值.
針對節理巖體非線性破壞特徵,髮展基于 Hoek-Brown 破壞準則的臨界滑動場理論進行節理巖體地基承載力的計算.首先將Hoek-Brown準則的剪切彊度逐點等效到Mohr-Coulomb彊度線上,求得每點的瞬時內摩抆角和瞬時黏聚力;在此基礎上,改進基于Mohr-Coulomb準則的臨界滑動場理論,建立新的迭代算法,將Hoek-Brown彊度準則與臨界滑動場理論結閤起來,求解被動土壓力和地基承載力.同時,綜閤分析GSI和mi值對地基承載力的影響.算例對比分析結果錶明,該方法能迅速準確地確定節理巖體地基最危險破壞滑麵併得到相應的地基極限承載力值.
침대절리암체비선성파배특정,발전기우 Hoek-Brown 파배준칙적림계활동장이론진행절리암체지기승재력적계산.수선장Hoek-Brown준칙적전절강도축점등효도Mohr-Coulomb강도선상,구득매점적순시내마찰각화순시점취력;재차기출상,개진기우Mohr-Coulomb준칙적림계활동장이론,건립신적질대산법,장Hoek-Brown강도준칙여림계활동장이론결합기래,구해피동토압력화지기승재력.동시,종합분석GSI화mi치대지기승재력적영향.산례대비분석결과표명,해방법능신속준학지학정절리암체지기최위험파배활면병득도상응적지기겁한승재력치.
Considering the nonlinear failure characteristics of jointed rock mass,the critical slip field method is modified based on the generalized Hoek-Brown failure criterion to calculate the bearing capacity of joined rock mass foundation. By transforming the shear strength of each point on the Hoek-Brown strength envelope into the Mohr-Coulomb linear relation,transient internal friction angle and cohesion of each point are calculated;and the critical slip field method based on the Mohr-Coulomb criterion is improved and a new iterative procedure is thus established. Using the newly developed critical slip field method based on the Hoek-Brown failure criterion,the passive earth pressure and ultimate bearing capacity of jointed rock mass foundation are computed. The effects of values of GSI and mi on ultimate bearing capacity of foundation are comprehensively analyzed. The results of comparative studies show that the proposed method can accurately determine the critical slip surfaces and associated values of ultimate bearing capacity of jointed rock mass foundation with reasonable accuracy.