Study On Mechanical Properties And Working Depth Of Reclaimed Soft Ground In Port

Land reclamation has become an important resort in solving the land-scare issue forport construction in highly-developed coastal areas. Since large settlement will occur underthe action of load in dredged fill ground of port, it is an important research topic to controlthe depth of working area in the port in order to avoid excessive deformation. This thesisdeals with the equivalent resilient modulus and the depth of working area of the reclaimedground in port systematically by theoretical calculation, field test and numerical simulation.According to the existing analytic formula for working depth，the equivalent thicknessmethod is adopted to modify the Boussinesq solution and the depth of working area isdefined by choosing the ratio of additional stress to geostatic stress to be0.1. The values ofoptimized thickness of the sand cushion covered by different pavement structures underdesign load in the port are obtained through calculation.The field loading test and compactness test are conducted on the soft ground in theport. As the thickness of sand cushion increases, the resilient modulus of the foundationincreases.The resilient modulus values are discrete when the thickness of sand cushion isrelatively small as the ground is hard to be fully compacted. The additional stress of thefoundation is measured through field full-scale test under the load of containers and trailers.The test results show that the additional stress increases with the increase of the load anddecreases with the increase of the depth. The corresponding depths of working area coveredby different pavement structures are also obtained.The numerical model establisted by the finite difference software FLAC3Dis modifiedaccording to the field test results. The distribution rule of additional stress, the ratio ofadditional stress to geostatic stress, the vertical strain and lateral displacement of differentpavement structures under design load are studied. The values of optimized thickness of thesand cushion covered by different pavement structures under the specified load are alsoobtained.The achievements of this thesis can provide valuable references for the Design Codeof Road and Stockyard for PortArea.