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
11期
2170-2184
,共15页
周辉%李震%杨艳霜%张传庆%盛谦
週輝%李震%楊豔霜%張傳慶%盛謙
주휘%리진%양염상%장전경%성겸
岩石力学%岩石材料%统一能量屈服准则%剪切应变能%体积应变能
巖石力學%巖石材料%統一能量屈服準則%剪切應變能%體積應變能
암석역학%암석재료%통일능량굴복준칙%전절응변능%체적응변능
rock mechanics%rock material%unified energy yield criterion%shear strain energy%volumetric strain energy
不同于金属材料,岩石材料由于具有内摩擦特性而表现出明显的 Lode 角效应等特点,其屈服过程不仅与广义剪应力有关,还受静水压力的影响。为建立适用范围更广、更符合岩石屈服机制的屈服准则,开展如下主要工作:综合考虑岩石材料屈服时的剪切滑移和法向压密机制,将与屈服相关的能量划分为3个复合滑动面的剪切应变能之和与体积应变能,并给出相应的计算公式;几种不同性质的岩石试验结果表明,岩石屈服时的2种能量近似符合线性关系,基于此,建立岩石统一能量屈服准则,总体上它可较好地描述岩石材料的屈服特性,如子午面上的曲线形态、Lode角效应等;通过对常用的岩石屈服准则进行对比分析,指出统一能量屈服准则是多种常用岩石屈服准则的一般形式;分别采用统一能量屈服准则、三剪能量屈服准则、Mohr-Coulomb 屈服准则、Drucker-Prager屈服准则、双剪强度理论、Hoek-Brown准则和Murrell准则对3种不同性质岩石的屈服强度进行计算,结果表明统一能量屈服准则的计算结果比较精确(尤其是在高围压和高静水压力条件下),并且分析统一能量屈服准则产生上述结果的本质机制,探讨岩石材料屈服时剪切应变能为定值的传统假设近似成立的条件。所建立的岩石统一能量屈服准则突破了岩石材料屈服时剪切应变能为定值的传统假设,通过分析体积应变能对岩石屈服的影响规律,在屈服准则中合理地考虑体积应变能的影响因素,这对于准确地定量分析岩石材料的屈服特性具有重要意义。
不同于金屬材料,巖石材料由于具有內摩抆特性而錶現齣明顯的 Lode 角效應等特點,其屈服過程不僅與廣義剪應力有關,還受靜水壓力的影響。為建立適用範圍更廣、更符閤巖石屈服機製的屈服準則,開展如下主要工作:綜閤攷慮巖石材料屈服時的剪切滑移和法嚮壓密機製,將與屈服相關的能量劃分為3箇複閤滑動麵的剪切應變能之和與體積應變能,併給齣相應的計算公式;幾種不同性質的巖石試驗結果錶明,巖石屈服時的2種能量近似符閤線性關繫,基于此,建立巖石統一能量屈服準則,總體上它可較好地描述巖石材料的屈服特性,如子午麵上的麯線形態、Lode角效應等;通過對常用的巖石屈服準則進行對比分析,指齣統一能量屈服準則是多種常用巖石屈服準則的一般形式;分彆採用統一能量屈服準則、三剪能量屈服準則、Mohr-Coulomb 屈服準則、Drucker-Prager屈服準則、雙剪彊度理論、Hoek-Brown準則和Murrell準則對3種不同性質巖石的屈服彊度進行計算,結果錶明統一能量屈服準則的計算結果比較精確(尤其是在高圍壓和高靜水壓力條件下),併且分析統一能量屈服準則產生上述結果的本質機製,探討巖石材料屈服時剪切應變能為定值的傳統假設近似成立的條件。所建立的巖石統一能量屈服準則突破瞭巖石材料屈服時剪切應變能為定值的傳統假設,通過分析體積應變能對巖石屈服的影響規律,在屈服準則中閤理地攷慮體積應變能的影響因素,這對于準確地定量分析巖石材料的屈服特性具有重要意義。
불동우금속재료,암석재료유우구유내마찰특성이표현출명현적 Lode 각효응등특점,기굴복과정불부여엄의전응력유관,환수정수압력적영향。위건립괄용범위경엄、경부합암석굴복궤제적굴복준칙,개전여하주요공작:종합고필암석재료굴복시적전절활이화법향압밀궤제,장여굴복상관적능량화분위3개복합활동면적전절응변능지화여체적응변능,병급출상응적계산공식;궤충불동성질적암석시험결과표명,암석굴복시적2충능량근사부합선성관계,기우차,건립암석통일능량굴복준칙,총체상타가교호지묘술암석재료적굴복특성,여자오면상적곡선형태、Lode각효응등;통과대상용적암석굴복준칙진행대비분석,지출통일능량굴복준칙시다충상용암석굴복준칙적일반형식;분별채용통일능량굴복준칙、삼전능량굴복준칙、Mohr-Coulomb 굴복준칙、Drucker-Prager굴복준칙、쌍전강도이론、Hoek-Brown준칙화Murrell준칙대3충불동성질암석적굴복강도진행계산,결과표명통일능량굴복준칙적계산결과비교정학(우기시재고위압화고정수압력조건하),병차분석통일능량굴복준칙산생상술결과적본질궤제,탐토암석재료굴복시전절응변능위정치적전통가설근사성립적조건。소건립적암석통일능량굴복준칙돌파료암석재료굴복시전절응변능위정치적전통가설,통과분석체적응변능대암석굴복적영향규률,재굴복준칙중합리지고필체적응변능적영향인소,저대우준학지정량분석암석재료적굴복특성구유중요의의。
Unlike metals,rock materials show the Lode angle dependence and other characters in mechanical behavior as a result of frictional effect. Its yield process depends not only on generalized shear stress but also on hydrostatic pressure. In order to construct the unified yield criterion which is widely used and accordant with characters of rock,work and results are as follows. Firstly,considering shear slide and normal compaction,energy related to yield is divided into the sum of shear strain energy on combined mobilized plane together with volumetric strain energy and their formulas are also derived. Secondly,test results show that when rock yields the relationship between the two kinds of strain energy is linear. Based on the result,rock unified yield criterion is established and it can describe basic yield characters such as curves on meridian plane and Lode angle dependence. Thirdly,after the analysis of some widely used rock yield criterions,it is proposed that unified energy yield criterion is a generalized form of these yield criterions. Lastly,the yield strength is calculated and with the following criterions respectively:the unified energy yield criterion,the triple shear energy yield criterion, Mohr-Coulomb yield criterion,Drucker-Prager yield criterion,twin-shear strength theory,Hoek-Brown yield criterion and Murrell yield criterion. The result by the unified energy yield criterion is more accurate and the error is more stable as well especially under high confining pressure and hydrostatic pressure. The intrinsic mechanism of above-mentioned result is analyzed and the qualification of the traditional assumption that shear strain energy retains to be constant when rock yields is confirmed. So the unified energy yield criterion established in this paper breaks through the traditional assumption. The factor such as volumetric strain energy should be considered reasonably in the yield criterion by analyzing the influencing rule of it,which is significant for the accurate quantitative analysis of rock yield characters.