Geogrid Anti-wrapped Improved Soil Geobag Retaining Wallexperimental Research On Bearing Characteristics

The geotechnical bag retaining wall is a new type of reinforced earth retaining wall.It is a retaining wall structure formed by stacking geotechnical bags on the side of a slope.The geotechnical bag retaining wall has developed rapidly due to its simple structure,low cost,good reinforcement effect,and environmental protection.However,in engineering applications,the geobags are independent of the bag body,and the fillers in the bags are separated,so the geobag retaining wall has the disadvantage of poor overall performance in practical applications.The filling in the geotechnical bag is not limited,and it can be gravel,gravel,construction waste,or spoil excavated from the project,so that the waste can be treated and reused,which is economic and environmentally friendly.In this paper,it is proposed to improve the waste silty clay with cement,and use the improved cement soil as a geotechnical bag filler in the geotechnical bag retaining wall structure.The geogrid is then used to wrap the geotextile bag to form a composite reinforced earth retaining wall structure,so that the individual geobags are wrapped together by the geogrid to form a whole,and the bearing performance of the geobag retaining wall is improved.The main work and results of this paper are as follows:(1)Research on the basic properties of silty clay used in the experiment.Indoor geotechnical tests were conducted on the silty clay,and the physical and mechanical properties of the silty clay were measured.The analysis shows that the silty clay has a large water content and poor water stability,so it is not suitable as a filler in geotechnical bags.(2)Laboratory test of cement-modified silty clay.The silty clay is mixed with different proportions of cement for compaction test to obtain the maximum dry density and optimal water content of cement-modified soil.Put the cement and soil into the geotechnical bag for uniaxial compression test.According to the test data,the best cement dosage is 8%.(3)Research on model test of geogrid reverse package improved geotechnical bag retaining wall.Indoor model tests were carried out on natural unsupported soil slopes,improved geotechnical bag retaining walls,and geogrid reverse-encased geotechnical bag retaining walls.By comparing the ultimate bearing capacity of different working conditions,the settlement of the top of the slope,The horizontal displacement of the wall surface and the lateral earth pressure behind the retaining wall result in a geogrid reverse wrap improved geotechnical bag retaining wall structure that can effectively improve the bearing capacity of the retaining wall.(4)When the reinforcement length is the same,the slope ratio has an effect on the reinforcement effect of the geogrid reverse-enclosed improved geotechnical bag retaining wall.Through the indoor model research on the retaining walls with slope ratios of 1:0.25,1:0.5 and 1:0.75,the ultimate bearing capacity of each working condition,the settlement of the top of the slope body,the horizontal displacement of the wall surface,the back side of the retaining wall are analyzed The earth pressure and the strain of the geogrid laid in the soil body,it is concluded that the geogrid reverse package improved geotechnical bag retaining wall structure can improve the bearing performance of the retaining wall by increasing the slope ratio.(5)The FLAC~3DD numerical simulation analysis of the working conditions of the geogrid reverse wrap improved geotechnical bag retaining wall under rainfall conditions.The numerical simulation was used to verify the bearing capacity of the geogrid reversed improved geotechnical bag retaining wall under non-rainfall conditions,and compared with the results of the model test.Re-simulating the load-bearing performance of the geogrid reverse-encased improved geotechnical bag retaining wall under rainfall conditions,recommendations are made for areas with heavy rainfall.Favorable slope reinforcement measures.