格宾网加筋煤矸石路堤稳定性及其强化措施

煤矸石是煤炭开采加工等工业过程中形成的煤炭矿渣,由于其工业价值低而被作为废弃物。考虑到煤矸石矿区公路路基填料缺乏和遵循变废为宝的环保理念,某高速公路建设工程采用了煤矸石填筑路基,并采用了格宾网加筋土结构形式,然而,有关格宾网加筋煤矸石路基的工作性能方面的研究匮乏。为此,以该高速公路建设为依托,通过现场试验研究格宾网加筋煤矸石路堤的力学与变形特性；在此基础上,建立相应的三维数值模型,进一步分析格宾网加筋煤矸石路堤的稳定性及其加固强化措施。结果表明：在退台式格宾网箱墙面的卸荷作用和格宾网网兜效应共同作用下,墙面附近的竖向土压力较低；格宾网加筋挡墙是一种柔性结构,其墙后侧向土压力小于静止土压力；提出了在坡脚下方埋设格宾网箱的加固强化措施,该措施可通过改变坡脚下方土体的力学与变形状态以及潜在滑裂面的形状,来增大路堤的抗滑力,进而提高格宾网加筋路堤的稳定性。

Study on stability and strengthening measure of coal gangue embankment reinforced by gabion

Coal gangue is the coal slag formed in the industrial process of coal mining and processing, which is regarded as waste because of its low industrial value. Coal gangue was used to fill the roadbed in an expressway construction project, and the gabion mesh reinforcement structure was adopted. However, there is a lack of research on the working performance of gabion reinforced coal gangue subgrade. To this end, based on the construction of this expressway, the mechanics and deformation characteristics of gabion reinforced coal gangue embankment were studied through field test. Then, the corresponding three-dimensional numerical model was established to further analyze the stability of the gabion reinforced coal gangue embankment and its reinforcement measures. The results show that under the combined action of the unloading effect of the retreating gabion cage and the pocket effect of the gabion, the vertical earth pressure near the wall face is lower. Gabion reinforced retaining wall is a flexible structure. The lateral earth pressure behind the wall face is less than the static earth pressure. The reinforcement measure of burying gabion cages under the slope toe is proposed. This measure can increase the anti-sliding force of the embankment by changing the mechanics and deformation state of the soil under the slope toe and the shape of the potential sliding surface, thereby improving the stability of the gabion reinforced embankment.