Development and application of similar materials for pit excavation group model tests in soft soil
Considering the coupling effect issue prevalent in the continuous pit excavation,the similar material proportioning scheme was determined,then optimal proportioning materials were derived through orthogonal test.Subsequently,the model tests for pit excavation group were designed to investigate the deformation of the retaining structure and ground movement of the station pit in the middle under the influence of the coupling effect of pit excavations on both sides.The results show that the proportion of soil mixture that satisfies the similarity constant is(quartz sand∶talcum powder∶double fly powder∶bentonite∶water=0.27∶0.27∶0.232∶0.058∶0.17).Compared with station pit without adjacent excavations,the coupled soil arching effect behind the retaining walls leads to a decrease in horizontal stress and reduced earth pressure and deformation on the retaining structures,while also an increase in the settlement of the soil between pit excavations.The spacing between exca-vations is a major factor affecting the deformation of the supporting structure.When the most important influencing factor distance between adjacent pit excavations is between 1Hto 2H(excavation depth),the coupling effect on the side closer to 1 time the excavation depth is greater than that on the side closer to 2 times the excavation depth.
pit excavation groupsoft soilsimilar materiallaboratory model testretaining structureground settlement
万方数据
维普
