Numerical and test study on vertical vibration characteristics of pile group in slope soil topography

Qu, Liming; Ding, Xuanming; Zheng, Changjie; Chongrong, Wu; Cao, Gang

doi:10.1007/s11803-021-2026-7

Cited by 18 publications

(2 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, a shallow buried anchorage foundation was proposed for the Honghe bridge in Yunnan province, where the underlying stratum is inclined bedrock [4]. A pile composite foundation (PCF) with dissimilar pile lengths can significantly reduce the settlement and differential settlement of a foundation and is adopted to adjust the vertical and horizontal stiffness of a bearing stratum [5][6][7][8]. For a PCF with a dissimilar pile length over inclined bedrock, a more complex analysis is need for the key parameters, such as the penetration depth of the pile head, the load-sharing ratio (LSR) of the pile, the vertical stiffness of the PCF, and differential settlement.…”

Section: Introductionmentioning

confidence: 99%

The Vertical Behaviors of Dissimilar Pile Composite Foundations over Inclined Bedrock

Zhou,

Tan,

Yue

et al. 2024

Buildings

View full text Add to dashboard Cite

Pile composite foundations (PCFs) have been commonly applied in reinforcement engineering to adjust the vertical stiffness of foundations, due to the displacement control design criteria for foundations. PCFs that have dissimilar pile lengths, located over inclined bedrock, have shown significantly different vertical behaviors from PCFs with equal pile lengths, placed over a semi-infinite medium. However, the vertical behaviors of dissimilar PCFs over inclined bedrock cannot be predicted with the current theoretical methods, although they have been widely adopted in engineering. An analytical method is proposed in this investigation to analyze the vertical bearing characteristics of dissimilar PCFs over inclined bedrock. A pile–soil system is decomposed into fictitious piles and extended soil, and then a control equation to determine the axial force along the fictitious piles is established, stemming from the compatibility conditions between them. The vertical behaviors of dissimilar PCFs can be obtained by solving the control equation with iterative procedures, and the equation is verified by two field load tests of single piles from the Honghe bridge and a numerical case. Then, the settlement and load transfer behaviors of 3 × 1 dissimilar PCFs and their influence factors are analyzed, and the results are as follows. (1) Obvious differences can be observed concerning the axial force distribution, settlement w, and load-sharing ratio (LSR) of each pile element for different pile–soil stiffness ratios (Ep/Es). (2) The LSR of pile 1 increases from 0.074 to 0.253 for the rigid pile and from 0.062 to 0.161 for the flexible pile condition when the cushion stiffness Kc changes from 1 × 104 kN/m to 3 × 108 kN/m. The non-dimensional vertical stiffness of the foundation, N0/wdEs, increases from 10.21 to 28.95 for the rigid pile condition and increases from 8.69 to 14.44 for the flexible pile condition, when Kc increases from 1 × 104 kN/m to 4 × 105 kN/m. (3) The neutral layer depth of the pile zn, the average settlement w, and the differential settlement wd of each element head decrease with Kc, and no negative friction zone exists (zn = 0 m) for all the pile elements when Kc> 2 × 105 kN/m. (4) The N0/wdEs decreases with the distance between the pile bottom and the inclined bedrock Δ. For the rigid and flexible pile conditions, the N0/wdEs is 22.16 and 13.48 for Δ = 1 m, and 13.13 and 10.10 for Δ = 8 m. The wd reaches 16.7 mm and 4.0 mm for Δ = 1 m and Δ = 8 m, respectively. (5) The N0/wdEs increases almost linearly with an increase in l/d for the rigid pile condition, and it gradually decreases for the flexible pile condition. The developed model can improve the design and analysis of PCFs located over inclined bedrock under vertical loading.

show abstract

Section: Introductionmentioning

confidence: 99%

The Vertical Behaviors of Dissimilar Pile Composite Foundations over Inclined Bedrock

Zhou,

Tan,

Yue

et al. 2024

Buildings

View full text Add to dashboard Cite

show abstract

“…The dynamic interaction between the pile and the foundation soil was not sufficiently studied due to the complexity of the vibrogenerator-pile-foundation soil model [16]. The studied dynamic models of the interactions of vibrogenerator-pile-foundation soil are theoretical models [17][18][19], numerical simulations models [20] and experimental models (in situ or indoor tests) [21][22][23]. Numerical simulation and, especially, analytical modeling of the movement of vibrating piles in saturated soil is quite difficult [24].…”

Section: Introductionmentioning

confidence: 99%

Dynamic Response of Vibratory Piling Machines for Ground Foundations

2022

View full text Add to dashboard Cite

Vibrating technological equipment for the introduction of piles and columns into the ground of construction foundations (named vibratory piling machines) is crucial in the process of building stable and resilient foundations for civil engineering, hydrotechnical construction, special construction (e.g., military constructions), bridges, roads and industrial platforms. During the works carried out by the construction companies in various geographical areas of Romania, particularities of the dynamic technological regimes influenced by the nature of the land were identified at the deep introduction of the construction elements in the form of piles or circular (tubular) columns. The results of applied research, rheological modeling and optimization of vibrating equipment, highlight the need for an analytical approach that takes into account the parametric variations of the elastic and damping characteristics of some categories of soils on the depth of piles or foundation columns. In this context, the paper presents the calculation model with the dynamic response for the vibrating equipment of insertion with disturbing forces of 200–1250 kN for piles or columns with lengths of 10–30 m. The novelty of the research study consists in the linear rheological model, which was adopted in the form of a Maxwell–Voigt–Kelvin schematic of the type (E-V)–(E|V), with a discrete variation in four values for stiffness and damping of the soil, as the piles or columns vibrate and advance in the ground foundation. Practical experience of the authors in the field of using vibrogenerators for the introduction of piles in various types of ground foundations led to the adoption of the rheological model with variable damping coefficients depending on the depth of penetration into the soil. The curves of the dissipated power confirm the experimental data obtained in situ, in accordance with the rheological indoor tests of the different types of soil foundations.

show abstract

Vertical vibration of piles with square cross‐section

Yang

Ding

et al. 2021

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

The paper presents an approximate solution to axial dynamic impedance calculation for group of square piles. Firstly, dynamic responses of the single pile‐soil system are derived on the basis of Hamilton's energy principle and variation analysis. Then, the effects of square cross section on the pile‐soil interaction are examined through the combination of theoretical deduction and numerical simulation. The vertical soil vibration around a square pile is found to be dependent on wave propagation directions in the near field (two times less than the side length of square pile). As the radial distance off pile axis increases, the soil vibration tends to be independent on propagation directions. Through superposition principle, the dynamic impedance of square pile group is calculated. This study could provide a reference to the problems with how the non‐circular piles interplay with soil on vibration.

show abstract

Numerical and test study on vertical vibration characteristics of pile group in slope soil topography

Cited by 18 publications

References 33 publications

The Vertical Behaviors of Dissimilar Pile Composite Foundations over Inclined Bedrock

The Vertical Behaviors of Dissimilar Pile Composite Foundations over Inclined Bedrock

Dynamic Response of Vibratory Piling Machines for Ground Foundations

Vertical vibration of piles with square cross‐section

Contact Info

Product

Resources

About