多级加筋土复合式挡墙的现场试验

FIELD TEST OF MULTISTAGE REINFORCED EARTH COMPOSITE RETAINING WALL

在现场对由L型挡土墙与加筋土挡墙形成的多级加筋土复合式挡墙进行了原位试验。试验表明:土压力和拉筋应变随上覆填土厚度增加而增大,但增速却减小;L型挡土墙的加筋土体底部竖向土压力沿筋长方向在加筋土施工期间呈非残性分布,在其上的中且上级模块式加筋土挡墙的竖向土压力施工期呈明显的非线性分布,但最大值均靠近拉筋尾部;L型加筋土挡墙的拉筋应变非常小,且曲线只有一个峰值;模块式加筋土挡墙的加筋土体底部竖向土压力沿筋长方向起初呈线性分布且大小基本相同,但随着填土厚度的增大而呈明显的非线性分布,且出现双峰值;中、上级挡墙的墙面板基底竖向应力随填土厚度的变化形式基本一样,且随填土厚度的增大先是内侧大于外侧,而后是外侧大于内侧;模块式加筋土挡墙的墙背侧向土压力沿墙高、拉筋应变沿筋长方向均呈非线性分布,且实测值均较小。

A muhistage reinforced earth composite retaining wall composed of L-type retaining wall and reinforced earth retaining wall was investigated in situ. The test results showed that the measured values of earth pressures and tensile strains in geogrid-reinforcement of the multistage reinforced earth composite retaining wall growed with the increasing of fill height, while the growth rates of those decreased; the vertical earth pressure of reinforced soil at the bottom of the L-type earth retaining wall was nonlinear distributing along the length of geogrid-reinforcement under construction, then obvious nonlinear distributing was observed on the above concrete-block reinforced earth retaining wall under construction, but the maximum values were close to the end of geogrid-reinforcement; tensile strains of geogrid-reinforcement of that were very small, and had only one peak; the vertical stresses at the bottom of the concrete-block reinforced earth retaining wall were first equivalencelinear and then non-linear along the geogrid- reinforcement length with the iucreasing of the fill height, and had two peaks; their change forms were the same, and the one of the inside bottom were first larger and then smaller than that of outboard; the lateral earth pressure on concrete-block wall was non-linear distributing along wall height, and the tensile strains of geogrid-reinforcement were non-linear distributing along the length of gengrid-reinforcement, but the measured values were lesser.