Settlement Of Soft Clay Research Articles

Ground Subsidence Investigation in Fuoshan, China, Based on SBAS-InSAR Technology with TerraSAR-X Images

Highways built on soft clay subgrade are more prone to subsidence due to the geotechnical characteristics of soft clay. Monitoring ground movements in this area is significant for understanding the deformation dynamics and reducing maintenance cost as well. In this paper, small baseline subset synthetic aperture radar interferometry (SBAS-InSAR) technique is exploited to obtain and investigate the time series ground surface deformation after the construction of a road embankment over soft clay settlement. Considering the important effect of temporal deformation models on the final accuracy of estimated deformation, both the linear velocity model and seasonal deformation model are utilized to conduct the comparative investigation of deformation time series. Two highways in Fuoshan, China—G1501 Guangzhou Belt Highway and Lungui Highway—were selected as the test area. Thirteen TerraSAR-X images acquired from October 2014 to November 2015 were analyzed. Comparative study based on two groups of analyses generated from the two models for both highways were conducted. Consequently, several feature points distributed near the two highways were analyzed in detail to understand the temporal evolution of the settlement. In order to evaluate the reliability of our measurements, the residual phase was analyzed to assess the modelling accuracy of the two models. In addition, leveling data were also used to validate the experimental results. Our measurements suggest that the seasonal model is more suitable for the test highways, with an accuracy of ±3 mm with respect to the leveling results.

Mathematical solution of the stone column effect on the load bearing capacity and settlement using numerical analysis

The most important application of various geotechnical construction techniques is for ground improvement. Many soil improvement project had been developed due to the ongoing increase in urban and industrial growth and the need for greater access to lands. Stone columns are one of the best effective and feasible techniques for soft clay soil improvement. Stone columns increase the bearing capacity and reduce the settlement of soil. Finite element analyses were performed using the program PLAXIS 2D. An elastic-perfectly plastic constitutive relation, based on the Mohr–Coulomb criterion, governs the soft clay and stone column behaviour. This paper presents on how the response surface methodology (RSM) software is used to optimize the effect of the diameters and lengths of column on the load bearing capacity and settlement of soft clay. Load tests through the numerical modelling using Plaxis 2D were carried out on the loading plate at 66 mm. Stone column load bearing capacity increases with the increasing diameter of the column and settlement decreases with the increasing length of the column. Results revealed that the bigger column diameter, the higher load bearing capacity of soil while the longer column length, the lower settlement of soil. However, the optimum design of stone column was varied with each factor (diameter and length) separately for improvement.

Settlement Research and Prediction on Soft Clay Foundation

Soft clay can be found in many places around the country of China. Along with the rapid economic development in coastal areas, civil engineers could meet many soft soils. These settlements appear quickly and may continue for a long period of time due to the consolidation behavior. This paper investigates the deformation characteristics of soft clay foundation from trial dates. Support Vector Machine model is proposed to predict settlement of soft clay. The settlement forecasting show Support Vector Machine method has advantages in its simple structure excellent capability in studying and good application prospects. The results of this study proves the elasto-viscoplastic model rationality based on laboratory test and have shown the SVM approach has the potential to be a practical tool for predicting settlement of soft clay foundation.