建筑垃圾与土工合成材料界面性能试验研究

Experimental Study on Interface Properties of Constructions and Demolition Waste and Geosynthetics

建筑垃圾与土工合成材料的界面剪切性能直接影响建筑垃圾作为填料在加筋土结构中的应用。通过大型直剪试验研究了建筑垃圾的含水率和土工合成材料的种类对建筑垃圾与土工合成材料界面剪切性能的影响。建筑垃圾的含水率为1%、6%、12%和18%的4种状态。土工合成材料分别为双向塑料土工格栅、双向玻纤土工格栅和无纺土工布。试验结果表明提高建筑垃圾含水率会降低建筑垃圾与土工合成材料界面的峰值剪应力;对比不同的土工合成材料,含水率相同时,建筑垃圾与双向塑料土工格栅的界面峰值剪应力最大,其与双向玻纤土工格栅、无纺土工布的界面峰值剪应力接近;建筑垃圾与土工合成材料的界面相互作用系数高于天然填料与土工合成材料的相互作用系数。

The interface shear properties of construction and demolition waste(C&DW) and geosynthetic directly affect the application of C&DW as filler in reinforced soil structure.In this paper, the effects of the C&DW moisture content and the types of geosynthetics on the interaction of C&DW and geosynthetics are studied using large-scale direct shear test. Four C&DW with different moisture contents(1%, 6%, 12% and 18%) were used in this study. Meanwhile,three different geosynthetics were used in this research: a biaxial extruded geogrid,a biaxial woven geogrid and a non-woven geotextile. The test results show that increasing in C&DW moisture content can reduce the peak interface shear stress. Refer to the types of geosynthetics,when the moisture content is the same, the peak shear stress at the interface of C&DW and the biaxial extruded geogrid is maximum, and this value of the biaxial woven geogrid is approach to the value of nonwoven geotextile. The cofficient of interaction of C&DW and geosynthetics interface is higher than that of natural filler and geosynthetics.