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
2014年
12期
2573-2581
,共9页
王贺%杨广庆%吴连海%刘华北%熊保林
王賀%楊廣慶%吳連海%劉華北%熊保林
왕하%양엄경%오련해%류화북%웅보림
土力学%返包式%土工格栅%加筋土挡墙%模型试验
土力學%返包式%土工格柵%加觔土擋牆%模型試驗
토역학%반포식%토공격책%가근토당장%모형시험
soil mechanics%wrapped face%geogrids%reinforced retaining wall%model test
为了研究返包式土工格栅加筋土挡墙在墙顶荷载作用下的受力和变形状态,分析其作用机制,通过室内模型试验,进行包括加筋土墙体垂直和水平土压力、应力扩散角、侧土压力系数、墙面水平变形和竖向沉降及土工格栅拉伸应变等分布规律的研究。试验结果表明:加筋土挡墙内垂直土压力沿筋材长度方向呈非线性分布,最大值位置从加载前位于筋材中部附近逐渐移动到加载点下;靠近墙面位置侧土压力沿墙高逐渐从加载前与自重应力线性相关变化为加载后从高到低逐渐减小的分布规律,其值小于主动土压力;实测应力扩散角较非加筋土体大,稳定的应力扩散角约为50°;侧土压力系数与荷载大小成正比,其沿墙高分布规律与水平土压力相似;墙面累积水平位移沿墙高呈“S”形曲线分布,最大值位于中下部;筋材应变沿其长度方向呈单峰值和双峰值的分布,峰值出现位置距墙脚的水平距离从高到低逐渐减小。
為瞭研究返包式土工格柵加觔土擋牆在牆頂荷載作用下的受力和變形狀態,分析其作用機製,通過室內模型試驗,進行包括加觔土牆體垂直和水平土壓力、應力擴散角、側土壓力繫數、牆麵水平變形和豎嚮沉降及土工格柵拉伸應變等分佈規律的研究。試驗結果錶明:加觔土擋牆內垂直土壓力沿觔材長度方嚮呈非線性分佈,最大值位置從加載前位于觔材中部附近逐漸移動到加載點下;靠近牆麵位置側土壓力沿牆高逐漸從加載前與自重應力線性相關變化為加載後從高到低逐漸減小的分佈規律,其值小于主動土壓力;實測應力擴散角較非加觔土體大,穩定的應力擴散角約為50°;側土壓力繫數與荷載大小成正比,其沿牆高分佈規律與水平土壓力相似;牆麵纍積水平位移沿牆高呈“S”形麯線分佈,最大值位于中下部;觔材應變沿其長度方嚮呈單峰值和雙峰值的分佈,峰值齣現位置距牆腳的水平距離從高到低逐漸減小。
위료연구반포식토공격책가근토당장재장정하재작용하적수력화변형상태,분석기작용궤제,통과실내모형시험,진행포괄가근토장체수직화수평토압력、응력확산각、측토압력계수、장면수평변형화수향침강급토공격책랍신응변등분포규률적연구。시험결과표명:가근토당장내수직토압력연근재장도방향정비선성분포,최대치위치종가재전위우근재중부부근축점이동도가재점하;고근장면위치측토압력연장고축점종가재전여자중응력선성상관변화위가재후종고도저축점감소적분포규률,기치소우주동토압력;실측응력확산각교비가근토체대,은정적응력확산각약위50°;측토압력계수여하재대소성정비,기연장고분포규률여수평토압력상사;장면루적수평위이연장고정“S”형곡선분포,최대치위우중하부;근재응변연기장도방향정단봉치화쌍봉치적분포,봉치출현위치거장각적수평거리종고도저축점감소。
Large-scale model tests in laboratory were carried out to study the behaviors of geogrids reinforced retaining wall of wrapped face under the loading on top of the retaining wall. The vertical and horizontal soil pressures,the stress diffusion angle,the coefficient of lateral soil pressure,the lateral displacement and the vertical settlement of wall face and the tension strain of geogrids were measured. The distribution of the vertical soil pressure along the geogrid length was found to be nonlinear and the position of the maximum pressure was moved from the middle of geogrids to the position under the loading point. The distribution of the lateral soil pressure along the wall height near the wall face increased linearly along the wall depth due to gravitational stress before loading and decreased along the wall depth after the overhead loading. The values of the lateral soil pressure were always smaller than the active earth pressure. The measured stress diffusion angle was greater than that of soil mass without geogrids and the stable values of the stress diffusion angle was 50°. The coefficient of lateral soil pressure was in direct proportion to the overhead loading,and its distribution along the wall height was similar to that of horizontal soil pressure. The cumulative lateral displacement of wall face had a distribution curve of S-shape,and its maximum value was located in the lower middle. The strain distributions of geogrids along its length were the curves of single-peak or twin-peak and the horizontal distance from the position of peak strains to the wall foot decreased gradually along the wall height.