Experimental Research On Reinforcement Techniques Of The Recent Dredger Fill Ultra-soft Foundation

Vacuum preloading method has been proved effective on the soft base treatment application in Tianjin port recent several decades. However, the duration of the land reclamation and engineering construction become shorter and shorter in the development of Binhai new area. There are still many problems need to be studied in the foundation treatment application of Vacuum preloading method.The land reclamation project is carried out at an unprecedented rate in Tianjin Harbor Industrial Park which is newly developed regional project to meet the upcoming infrastructure construction and investment attraction. Due to the large-scale development and construction, foundation treatment should conquer the difficulties including the time urgency, ultra-soft soil like silt, silty soil and even mud fluid which raise the costs and difficulties of the sand and soil material transportation, and that large machinery can not be admitted et al.Based on the work of former researchers, Vacuum preloading method applied in the shallow foundation treatment is studied considering the actual soil circumstance in Tianjin harbor. Research works are conducted as follows:(1) Calculation methods of the consolidation degree, sedimentation and ground bearing capacity in the shallow foundation treatment are analyzed, and laminar summation method is used to calculate the sedimentation.(2) The variations of the physical and mechanical properties before and after reinforcement are compared based on the analysis of the field test data. The variation process of the layer settlement, laminar settlement, pore water pressure and lateral displacement is monitored.(3) Construction techniques are improved based on the experiments considering the soil property of the harbor and lack of the sand and soil.(4) The economic analysis of the improved construction techniques is carried out.