土工格栅加筋土地基平板载荷试验研究

Experimental study of geogrid-reinforced soil foundation by plate load test

在近年来的岩土工程实践中,土工合成材料加筋土技术得到越来越广泛的应用。采用平板载荷板试验方法,进行了多组加筋砂土地基模型试验,监测和分析了不同加筋材料(双向格栅与四向格栅)和加筋层数对土工格栅加筋土地基承载特性的影响。研究结果表明:土工格栅加筋土地基与无筋地基相比,承载性能得到改善,双层加筋明显优于单层加筋;土工格栅加筋限制了浅层地基的侧向变形,相同荷载下地基沉降减小,可恢复变形增大;模型试验中测得加筋材料应变和拉力很小,与土工格栅强度相比,拉伸模量对加筋土地基承载力的贡献更大。

The technology of geosynthetic reinforced soils is applied more and more widely in recent geotechnical engineering practice. For further study of reinforced soil foundation, the authors carried out several plate load tests of geosynthetics reinforced sand soil foundation, the influences of different reinforcing materials （biaxial geogrid and quaxial geogrid） and the number of reinforcing layers on the bearing characteristics of geogrid reinforced sand soil foundation are monitored and analysed. The results show that： comparing with sand soil foundation without reinforcement, the bearing behavior of geogrid reinforced sand soil foundation are improved, and the effect of two-layer reinforcement is significantly better than one-layer reinforcement. Lateral deformation of the shallow foundation is confined by the geogrid reinforcement; and the settlements of geogrid-reinforced sand soil foundation decreased under the same load; and the recoverable rebound deformation increased. The monitored strain and tension of the reinforcing material during the loading progress are very small; and the tensile modulus of the reinforcements contributes greater to the bearing capacity of the geogrid-reinforced sand soil foundation than the strength of the reinforcements.