岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
4期
1141-1146
,共6页
基底应力分布%FPA假设%应力凹陷%剪应力分布假设
基底應力分佈%FPA假設%應力凹陷%剪應力分佈假設
기저응력분포%FPA가설%응력요함%전응력분포가설
basal stress distribution%FPA assumption%depression of stress%shear stress distribution assumption
对砂堆三棱柱的基底应力分布及应力凹陷现象进行了研究,基于固定主应力轴假设(FPA假设)将砂堆分为应力状态已知的I区和应力状态未知的II区,并假设了II区内的多种剪应力分布来求解II区内的应力状态,最后,将不同剪应力分布假设下砂堆中线上的静止土压力系数值与Kulhawy公式计算值对比,可得出如下结论:基底法向应力存在应力凹陷现象,自然休止角越大(砂堆越紧密),应力凹陷程度、应力凹陷范围越大;不同剪应力分布假设下,II 区应力分布形态不同,法向应力极小值所在处也不同。剪应力二次方分布假设和三次方假设下砂堆基底应力分布最为合理、最为符合真实情形。
對砂堆三稜柱的基底應力分佈及應力凹陷現象進行瞭研究,基于固定主應力軸假設(FPA假設)將砂堆分為應力狀態已知的I區和應力狀態未知的II區,併假設瞭II區內的多種剪應力分佈來求解II區內的應力狀態,最後,將不同剪應力分佈假設下砂堆中線上的靜止土壓力繫數值與Kulhawy公式計算值對比,可得齣如下結論:基底法嚮應力存在應力凹陷現象,自然休止角越大(砂堆越緊密),應力凹陷程度、應力凹陷範圍越大;不同剪應力分佈假設下,II 區應力分佈形態不同,法嚮應力極小值所在處也不同。剪應力二次方分佈假設和三次方假設下砂堆基底應力分佈最為閤理、最為符閤真實情形。
대사퇴삼릉주적기저응력분포급응력요함현상진행료연구,기우고정주응력축가설(FPA가설)장사퇴분위응력상태이지적I구화응력상태미지적II구,병가설료II구내적다충전응력분포래구해II구내적응력상태,최후,장불동전응력분포가설하사퇴중선상적정지토압력계수치여Kulhawy공식계산치대비,가득출여하결론:기저법향응력존재응력요함현상,자연휴지각월대(사퇴월긴밀),응력요함정도、응력요함범위월대;불동전응력분포가설하,II 구응력분포형태불동,법향응력겁소치소재처야불동。전응력이차방분포가설화삼차방가설하사퇴기저응력분포최위합리、최위부합진실정형。
This paper focuses on the basal stress distribution and depression of stress of sand prism. The sand prism is divided into a stress known zone I and a stress unknown zone II based on the fixed principal axes (FPA) assumption. On several shear stress distribution assumptions, the stress state of zone II is available. The values of coefficient of earth pressure at rest on the sand centerline on different shear stress distribution assumptions are compared to the one proposed by Kulhawy. The following results are achieved;there is depression of normal stress on the base of sand prism, and the larger of the friction angle (the denser the sand prism) is, the more the depression of normal stress is; and the larger of the depression range is; the shape of the stress distribution and minimum value of normal stress and the location of the minimum normal stress are different on different assumptions; and the assumption of quadratic distribution and cubic distribution of shear stress are most reasonable.