人民长江
人民長江
인민장강
YANGTZE RIVER
2015年
8期
56-60
,共5页
黄土%结构演化%归一化%UU 试验%结构性参数
黃土%結構縯化%歸一化%UU 試驗%結構性參數
황토%결구연화%귀일화%UU 시험%결구성삼수
loess%structural evolution%normalized%unconsolidated - undrained shear test%structural parameter
结构性对黄土的承载力、变形特点以及强度具有重要影响。为研究未受扰动情况下黄土的结构性演化,采用不固结不排水剪切试验的方法,研究黄土在常规三轴应力条件下压-剪过程中结构性演变的宏观试验规律。试验结果表明,初始含水率增加使黄土应力应变曲线从软化型向硬化型发展,围压增大促使应力应变曲线由弱硬化向相对强硬化转变,围压和含水率都对结构性演变具有重要影响。土结构在未受固结扰动的情况下,围压和初始含水率影响了结构演变的路径,低围压下结构衰减要快于高围压下;低含水率时,结构性衰减对围压较敏感,含水率升高后敏感程度降低。
結構性對黃土的承載力、變形特點以及彊度具有重要影響。為研究未受擾動情況下黃土的結構性縯化,採用不固結不排水剪切試驗的方法,研究黃土在常規三軸應力條件下壓-剪過程中結構性縯變的宏觀試驗規律。試驗結果錶明,初始含水率增加使黃土應力應變麯線從軟化型嚮硬化型髮展,圍壓增大促使應力應變麯線由弱硬化嚮相對彊硬化轉變,圍壓和含水率都對結構性縯變具有重要影響。土結構在未受固結擾動的情況下,圍壓和初始含水率影響瞭結構縯變的路徑,低圍壓下結構衰減要快于高圍壓下;低含水率時,結構性衰減對圍壓較敏感,含水率升高後敏感程度降低。
결구성대황토적승재력、변형특점이급강도구유중요영향。위연구미수우동정황하황토적결구성연화,채용불고결불배수전절시험적방법,연구황토재상규삼축응력조건하압-전과정중결구성연변적굉관시험규률。시험결과표명,초시함수솔증가사황토응력응변곡선종연화형향경화형발전,위압증대촉사응력응변곡선유약경화향상대강경화전변,위압화함수솔도대결구성연변구유중요영향。토결구재미수고결우동적정황하,위압화초시함수솔영향료결구연변적로경,저위압하결구쇠감요쾌우고위압하;저함수솔시,결구성쇠감대위압교민감,함수솔승고후민감정도강저。
The bearing capacity,deformation law and strength of loess are influenced by its structural characteristic. We con-centrate on the structural evolution of undisturbed loess by performing unconsolidated - undrained shear tests to investigate the structural evolution under regular triaxial test characterized as compact - shear stress condition. The results show that increase of the initial water content turns the stress - strain curves from softening type to hardening type,while the confining pressure incre-ment changes the stress - strain curves from weak hardening into relatively strong hardening,demonstrating that the two factors in-fluence the structural evolution significantly. When the loess is not disturbed by consolidation process,both the initial water con-tent and confining pressure have impacted on the structural evolution routine,the structure damps faster under lower confining pressure than it does under higher confining pressure. In a lower water content environment,the damping of the structure is more sensitive to confining pressure than it is under higher water content.