土工格室加固风积沙地基模型试验及力学特性研究

Study on model test and mechanical properties of aeolian sand foundation reinforced by geocell

目前对土工格室加固风积沙地基的最佳规格探究相对较少,市面上的格室规格较多,需对格室规格变化引起的力学性能变化规律进行探究。选用市面上7种不同高度及6种不同焊距的格室加固风积沙地基进行大型模型试验。试验结果表明:格室焊距越小,高度越高,其加固风积沙地基的性能越好。当格室焊距为500 mm、格室高度为50~200 mm时可以提高风积沙地基承载力2.75~4.29倍,当格室高度为100 mm时,格室焊距为300~800 mm时能提高风积沙地基承载力2.32~3.75倍。格室层在竖直和水平方向上均对荷载有分散作用,在竖直方向上尤为明显。当竖向沉降相同时,焊距相同的格室应变走势大致相同,高度相同的格室焊距越大条带应变越小,格室层条带的侧限作用越差,加固效果越差。选用高度×焊距为150 mm×500 mm的格室加固风积沙地基,效果最佳。

At present,there are relatively many specifications of geocell on the market,and there are relatively few studies on the best specifications of geocell reinforcement of eolian sand foundation,and it is necessary to explore the change law of mechanical properties caused by the change of geocell specifications.A large-scale model test was carried out on the aeolian sand foundation reinforced by geocell with 7 different heights and 6 different welding distances on the market.The test results show that:The smaller the welding distance and the higher the height of the geocell,the better the performance of the reinforced aeolian sand foundation.When the welding distance is 500 mm and the geocell height is 50~200 mm,the bearing capacity of aeolian sand foundation can be increased by 2.75~4.29 times,and when the height of the geocell is 100 mm,the welding distance of the geocell is 300~800 mm,which can improve the bearing capacity of the aeolian sand foundation by 2.32~3.75 times.The geocell layer has a dispersion effect on the load in both vertical and horizontal directions,especially in the vertical direction.When the vertical settlement is the same,the strain trend of the geocell with the same welding distance is roughly the same,and the larger the welding distance of the geocell with the same height is,the smaller the strain of the strip is,the worse the lateral confinement effect of the geocell layer is,and the worse the reinforcement effect is.The geocell with height×welding distance of 150 mm×500 mm has the best economic benefit in reinforcing aeolian sand foundation.