CAJ | 학술논문

为了研究复杂应力务件下的深基坑岩石细观破坏问题,本构方程采用由应变空间导出的弹塑性损伤细观力学模型,借助有限元计算方法,实现了岩石三维破裂过程的数值模拟.采用细观破坏单元网格消去法,实现了有限元模拟裂纹扩展过程;利用位移加载来实现岩石逐渐破裂过程;数值模拟灰岩单轴拉伸及压缩破坏试验、双轴拉伸破坏试验和三轴受压破坏试验,得到其非线性应力一应变曲线和不同载荷阶段弹塑性损伤破裂演化系列图像;分析细观非均匀性对岩石宏观破裂力学行为的影响.研究表明,在复杂应力条件下,随着围压增大,峰值抗压强度明显提高,塑性变形明显增大.本文研究对深基坑施工过程中预防工程事故的发生具有借鉴意义.
위료연구복잡응력무건하적심기갱암석세관파배문제,본구방정채용유응변공간도출적탄소성손상세관역학모형,차조유한원계산방법,실현료암석삼유파렬과정적수치모의.채용세관파배단원망격소거법,실현료유한원모의렬문확전과정;이용위이가재래실현암석축점파렬과정;수치모의회암단축랍신급압축파배시험、쌍축랍신파배시험화삼축수압파배시험,득도기비선성응력일응변곡선화불동재하계단탄소성손상파렬연화계렬도상;분석세관비균균성대암석굉관파렬역학행위적영향.연구표명,재복잡응력조건하,수착위압증대,봉치항압강도명현제고,소성변형명현증대.본문연구대심기갱시공과정중예방공정사고적발생구유차감의의.
In order to study the meso-damage mechanism of deep foundation of rock under complex stress conditions,the constitutive equations of the elasto-plastic meso-damage model,derived from the strain space micromechanics,were adopted in the finite element method to simulate numerically three-dimensional cracking process of the rock.The elimination of micro-damage elements was carried out in the finite element analysis to follow the extending process of cracks.The rock was loaded by displacement to its progressive failure process;the failure tests of the limestone,under loading cases of uni-axial tension/compression,bi-axial tension and tri-axial compression,were simulated numerically to obtain the nonlinear stress-strain curves and a series of images of cracking evolution at different stages of the loading,for the analysis of the influence of rock in-homogeneity on the macro-cracking mechanism of the rock.The results indicate that the peak values of compressive strength and the plastic deformation will increase significantly with the increment of the confining pressure.This study will be helpful to the prevention of engineering disasters in construction of deep foundations.