Settlement Prediction Of Artificial Island Revetment Considering Creep

Coastal cities have scarce land resources.In order to meet the needs of economic construction,more and more coastal cities adopt land reclamation to meet the demand for land.Since the foundation of the reclamation project is generally soft ground,it will face the problem of long-term settlement.In the current research on the settlement of soft soil foundations,only the main consolidation settlement stage is often considered,and the effect of creep deformation of soft clay on settlement is ignored.As a result,the actual settlement value exceeded the predicted value,which caused inconvenience to the subsequent normal operation of the project.Therefore,it is necessary to consider the creep deformation of soft soil in studying the settlement deformation of soft soil foundation.This paper is based on the research of an artificial island slope protection project in Dalian.In this paper,the soft clay in the revetment foundation is taken as the research object,and the creep deformation characteristics of the soft clay are analyzed on the basis of the test results of the soft clay creep test.Then the numerical simulation method is used to calculate the creep deformation in the creep test of soft clay,which verifies the applicability of the numerical simulation method.Finally,the settlement deformation of the artificial island revetment foundation is calculated and predicted.The main research content includes the following aspects:(1)Based on the test results of the triaxial creep test of soft clay,the "Chen method" is used to process the test data,and the creep deformation law of soft clay is analyzed.Studies have shown that there is a linear relationship between the stress and strain of soft clay in this area,and the creep deformation exhibits the characteristics of attenuation and stability.Then,this paper selects the Cvisc creep constitutive model that can respond to the viscoelastic plastic deformation of the soft clay to fit the strain-time change curve of the soft clay creep test.The results show that the fitting effect is good.It proves that the creep model is reliable.(2)To verify the effectiveness of the numerical simulation software FLAC3 D,this paper conducted numerical simulation calculations on the creep deformation of soft clay in the creep test.Then the results of the numerical simulation are compared with the test curve and the fitting curve,which verifies the applicability of this numerical simulation method in calculating the creep deformation of the soft clay.(3)On the basis of the above research,this paper performs settlement calculation on the soft ground of the artificial island revetment.First,a numerical model was established,and then the law of dissipation of excess pore water pressure in the soil layers of different depths in the foundation was studied.The main soil layers that caused the settlement of the found-ation were clay layers and silty clay layers.Finally,this paper analyzed two calculation results considering soft clay's creep deformation and not considering soft clay's creep deformation.Comparing the numerical simulation results with the actual monitoring data,the results show that it is very important to consider the creep deformation of soft clay when calculating the settlement of soft soil necessary.(4)Finally,the numerical simulation method is used to predict the settlement of the artificial island revetment foundation for 10 years,considering the creep deformation of soft clay.It was found that the area with the largest amount of foundation settlement after 10 years occurred on the right side of the revetment.The excess pore pressure in the foundation did not completely dissipate within 10 years.After that,creep settlement will be the main part of foundation settlement.