|
|
|
| Analytical model and solution for the longitudinal impedance of large-diameter pipe piles in radial inhomogeneous layered soils |
| LIANG Zhimeng1，CUI Chunyi1，XU Chengshun2，XIN Yu1，MENG Kun1，PEI Huafu3#br# |
(1. Department of Civil Engineering，Dalian Maritime University，Dalian，Liaoning 116026，China；2. Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education，Beijing University of Technology，Beijing 100124，China；3. State Key Laboratory of Coastal and Offshore Engineering，Dalian University of Technology，Dalian，Liaoning 116024，China)
|
|
|
|
|
Abstract In order to investigate the vertical vibration characteristics of large-diameter pipe piles embedded in bidirectional inhomogeneous soils，a mechanical model for longitudinal vibration of large-diameter pipe piles in radial inhomogeneous layered soils is established by considering the lateral inertia effect of large-diameter pipe piles and construction disturbance，based on the Rayleigh-Love rod model and Novak¢s plane-strain theory. The complex stiffness expression at the interface between the soil and the large-diameter pipe pile is obtained recursively by means of the Laplace transform and complex stiffness transfer techniques. Then the analytical solution for the dynamic impedance of large-diameter pipe piles is derived by using the completely coupling condition between pile and soil and the transitivity of the impedance function，and compared with the previous solutions to verify the validity and precision. Furthermore，parametric analyses are performed to investigate the effects of the parameters of pile and soil on the dynamic impedance of a large-diameter pipe pile. The results show that the Rayleigh-Love rod model and the relevant analytical solution are more appropriate to analyze the longitudinal vibration characteristics of large-diameter pipe piles than Euler-Bernoulli rod model which underestimates the amplitude and resonance frequency of the dynamic impedance. Keeping the inner(outer) diameter constant，the larger(smaller) the outer(inner) diameter，the higher the amplitude and resonance frequency of the dynamic impedance at the pile head. The softer(harder) the longitudinal interlayer of the surrounding soil，the larger the peak difference of the dynamic impedance curves. The greater the degree of softening(hardening) of the surrounding soil，the larger(smaller) the amplitude and resonance frequency of the dynamic impedance at the pile head. The disturbance range has a significant effect on the oscillation amplitude while little influence on the resonance frequency.
|
|
|
|
|
|
|
|
|
2021, Vol. 40 
