FEM Numerical Simulation of Electrical Flow in Cylindrical Soft Clay Core Samples for Construction of a Resistivity Correction Factor Chart

Safety of secondary lining is of utmost importance to tunnel engineering quality as the main load-bearing structure and the last waterproof line of rock tunnel under type III. The comparative study of strain state results from FEM numerical simulation and on-site monitoring in Yunnan Tianxin Tunnel was conducted to obtain the stress regularity of tunnel lining. The results showed that except vault, the strain states of secondary lining obtained by numerical simulation and on-site monitoring were consistent. The strain value of on-site monitoring was approximately 60%~70% to the simulation value. And the strain value of right side was greater than the value of the corresponding location on the left side. It’s noticed that high strain were found in tunnel haunch and arch springing. Great attention should be paid to arch springing for the largest strain value. The strain monitoring value of vault (309.83με~327.23με) has been detected larger than simulation value (209.37με), which matches well the crack phenomenon of vault. Therefore it’s significant to focus on the long-term monitoring of vault. The defects of single on-site monitoring method such as poor predictability were made up effectively by comparative study. The results achieved can be recommended for similar projects.

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Numerical Simulation of Pile-Soil Interaction Considering Sand Liquefaction under Earthquake

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.226-228.1019 ◽

2012 ◽

Vol 226-228 ◽

pp. 1019-1022 ◽

Cited By ~ 2

Author(s):

Pei Zhen Li ◽

Dong Ya Ma ◽

Da Ming Zeng ◽

Xi Lin Lu

Keyword(s):

Numerical Simulation ◽

Pore Water Pressure ◽

Water Pressure ◽

Soft Clay ◽

Soil Liquefaction ◽

Engineering Practice ◽

Saturated Sand ◽

Acceleration Response ◽

Sand Liquefaction ◽

Vibration Time

Liquefaction is one of the most important damages in pile foundation under earthquake. However, it is very difficult to analyze. Numerical simulation of pile-soil interaction considering saturated sand liquefaction under earthquake is conducted using OpenSees program. In this model, the soil is divided into soft clay soil and saturated sand, and the single pile is embedded in the soil. The results show that the pore water pressure rises and the soil liquefied as vibration time increases. With the nonlinear of the soil develop, the stiffness, bearing capacity and the acceleration response of the soil and the pile decrease, while the displacement response of the soil increases. Therefore, it is necessary to consider the soil liquefaction in the design and analysis in the engineering practice.

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