NUMERICAL SIMULATION OF DEEP EXCAVATION IN GRAVEL LAYERS

Abstract

This study analyzed gravel excavation cases in the Xindian District of Taiwan. Instead of the parameters typically employed in deep excavation analysis we used the deformations of diaphragm walls in a back analysis to achieve recommendations regarding the ideal range of the soil elastic modulus E-s in the analysis parameters of numerical simulations for the Xindian District stratum or similar strata. We used Plaxis 2D software to analyze the gravel layer. The results indicated that, when the fifth layer of gravel was set to N = 100 and the range of the soil elastic modulus Es was set between 7.84N and 9.8N MPa, where N is the N value of the Standard Penetration Test, the maximum deformation of the wall at the final excavation stage was satisfactorily estimated. A few studies have investigated the gravel layer of the Xindian District; therefore, the current study used the gravel layer of Bagua Mountain in the Changhua Region of Taiwan for conducting a comparison. Previous studies on the gravel layer of Bagua Mountain have reported that the soil elastic modulus Es of this layer ranged from 88.2 to 833 MPa, which is consistent with the empirically estimated range of the elastic modulus Es (180.3-980 MPa) in our study.