A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
NUMERICAL ANALYSIS OF STONE COLUMNS IN LIQUEFIABLE SOIL
AbstractStone columns are widely used to improve properties of cohesionless soils (i.e. stiffness and shear strength parameters) and decrease its susceptibility to liquefaction. Quality control is a crucial matter regarding stone column construction; and many field tests can be used to assess the in-situ stone column stiffness. Plate load test on single stone column is regularly used as one of these quality control methods. However, plate load test results do not clearly indicate stone column in-situ stiffness or the improvement in the field’s liquefaction resistance. A series of axisymmetric numerical simulations of plate load tests on stone columns is presented to investigate the relationship between the stone column stiffness (Ecol.) as an input parameter and that back analyzed stiffness (Eint) from the test results. The research also presents the results of plane-strain numerical models simulating a reference earthquake applied to a unit cell improved by a stone column to assess the change in liquefaction resistance with increasing column stiffness (Ecol.). The dynamic analyses compare between two well-known dynamic constitutive models; PM4Sand, and UBC3D-PLM. A verification was done for both soil models to ensure soil parameters and estimate pore water pressure calculation accuracy for undrained sand behavior under rapid dynamic loading. The degrees of improvement in liquefaction resistance predicted in the study agree well with that of theories based on combined shear and flexural stone column deformation mechanisms. Finally, the research presents a set of design curves which helps field engineers to assess the degree of improvement in liquefaction resistance from plate load test results by combining the results from static and dynamic simulations.
NUMERICAL ANALYSIS OF STONE COLUMNS IN LIQUEFIABLE SOIL
AbstractStone columns are widely used to improve properties of cohesionless soils (i.e. stiffness and shear strength parameters) and decrease its susceptibility to liquefaction. Quality control is a crucial matter regarding stone column construction; and many field tests can be used to assess the in-situ stone column stiffness. Plate load test on single stone column is regularly used as one of these quality control methods. However, plate load test results do not clearly indicate stone column in-situ stiffness or the improvement in the field’s liquefaction resistance. A series of axisymmetric numerical simulations of plate load tests on stone columns is presented to investigate the relationship between the stone column stiffness (Ecol.) as an input parameter and that back analyzed stiffness (Eint) from the test results. The research also presents the results of plane-strain numerical models simulating a reference earthquake applied to a unit cell improved by a stone column to assess the change in liquefaction resistance with increasing column stiffness (Ecol.). The dynamic analyses compare between two well-known dynamic constitutive models; PM4Sand, and UBC3D-PLM. A verification was done for both soil models to ensure soil parameters and estimate pore water pressure calculation accuracy for undrained sand behavior under rapid dynamic loading. The degrees of improvement in liquefaction resistance predicted in the study agree well with that of theories based on combined shear and flexural stone column deformation mechanisms. Finally, the research presents a set of design curves which helps field engineers to assess the degree of improvement in liquefaction resistance from plate load test results by combining the results from static and dynamic simulations.
NUMERICAL ANALYSIS OF STONE COLUMNS IN LIQUEFIABLE SOIL
Gamal Diaaeldin Abdelrazek, Adham (author)
2021-02-21
Article (Journal)
Electronic Resource
English
Effect of Discrete Columns on Shear Stress Distribution in Liquefiable Soil
| British Library Conference Proceedings | 2012