PFF复合反滤层及其在支挡工程中的应用研究

Study on PFF composite filter layer and its application in retaining engineering

为避免地下水对支挡结构的不利影响,需设置反滤层排除支挡工程背后岩土体的渗水。目前支挡工程多采用混凝土浇筑施工,受墙后空间狭小影响,常规的砂砾石反滤层不易压实,影响支挡工程受力和使用功能。文章结合反滤层的隔离挡土、过滤、排水等基本作用原理,研制开发了一种由隔水层、排水层、透水层相结合形成的具有墙背模板功能的PFF整体式复合反滤层,以适应混凝土支挡结构浇筑施工工法。试验工点排水试验表明,该新型反滤层排出水数量和效率均优于传统的砂砾石反滤层,可在支挡工程中推广应用。

In order to avoid the adverse effects of water on under the retaining structure. The construction materials retaining structure, filter layer is needed to set of retaining structure was changed from mortar rubble to concrete, then the construction method was also changed from masonry to cast-in-place concrete. Due to the narrow space, it is difficult to guarantee the quality and the compaction degree of the conventional sand gravel filter layer, thus the reliability of the retaining structure was affected. Base on the basic principle of the filter layer, such as isolation, filtration and drainage, a new type of geosynthetics filter layer is developed. The new filter layer, which possesses formwork feature, is formed by the combination of water- resisting layer, drainage layer and permeable layer. The efficiency of concrete retaining wall construction is significantly improved after using this new material. Site drainage test shows that discharge water quantity and efficiency of the new filter layer are better than the traditional sand gravel filter layer, which can be used in retaining engineering.