RETRACTED: Seismic response of mid-rise buildings on shallow and end-bearing pile foundations in soft soil

Two experimental areas in a highway soft soil ground treatment project in Guangdong Province were designed to investigate the improvement mechanism of geogrid-reinforced and pile-supported embankment(GRPS).The experimental results showed: In End-bearing Pile Area,the differential settlement between pile and soil was bigger than that of Floating Pile Area,so the bearing capacity of soil was exerted to a certain extent in Floating Pile Area. The bearing efficacy of soil below the pile cap was little, so the replacement ratio of composite foundation could be calculated according to the pile cap dimension. The load transfer efficacy of the geogrid was better than that of the soil arch. Five kinds of methods were used to evaluate the soil arch in the fill and it was indicated that the results calculated by the BS8006 method and Carlsson method was close to the experimental data which was smaller than results calculated by Hewlett method and Terzaghi method, bigger than Guido method. Through the analysis of the pile-soil stress ratio, the improvement mechanism of the two types of GRPS were revealed.

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Simple formulas for estimating a lumped parameter model to reproduce impedances of end-bearing pile foundations

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2019.02.021 ◽

2019 ◽

Vol 121 ◽

pp. 341-355 ◽

Cited By ~ 3

Author(s):

Michele Morici ◽

Lucia Minnucci ◽

Sandro Carbonari ◽

Francesca Dezi ◽

Graziano Leoni

Keyword(s):

Lumped Parameter Model ◽

Pile Foundations ◽

Lumped Parameter ◽

End Bearing Pile

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Numerical Modeling of Seismic Response of Rigid Foundation on Soft Soil

International Journal of Geomechanics ◽

10.1061/(asce)1532-3641(2008)8:6(336) ◽

2008 ◽

Vol 8 (6) ◽

pp. 336-346 ◽

Cited By ~ 76

Author(s):

M. H. Rayhani ◽

M. H. El Naggar

Keyword(s):

Numerical Modeling ◽

Seismic Response ◽

Soft Soil ◽

Rigid Foundation

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Power Analysis of Sdof Structures with Tuned Inerter Dampers Subjected to Earthquake Ground Motions

ASCE-ASME J Risk and Uncert in Engrg Sys Part B Mech Engrg ◽

10.1115/1.4049212 ◽

2020 ◽

Author(s):

Wenai Shen ◽

Zhentao Long ◽

Heng Wang ◽

Hongping Zhu

Keyword(s):

Seismic Response ◽

Output Power ◽

Analytical Solutions ◽

Ground Motions ◽

Soft Soil ◽

Response Control ◽

Seismic Response Control ◽

Earthquake Ground Motions ◽

Short Period ◽

Soil Site

Abstract Tuned inerter dampers (TID) have been demonstrated as efficient energy dissipation devices for seismic response control. However, its potential capability for energy harvesting remains largely unexplored. Here, we present a theoretical analysis of the power of a structure-TID system subjected to earthquake ground motions. The analytical solutions of the average damping power of the system are derived for considering white noise base excitations and the Kanai-Tajimi earthquake model, respectively. Comparisons of the numerical results of a Monte Carlo simulation and the theoretical predictions verify the accuracy of the analytical solutions. Besides, we uncover the influence of the TID parameters on the damping power and output power of the system. The optimal frequency ratio of the TID for maximizing its output power slightly differs from that for seismic response control, and the former varies with site conditions. In contrast, both the damping power and output power are not sensitive to the damping ratio of the TID. For short-period structures, a small inertance-to-mass ratio (µ) of the TID is beneficial to maximize its output power, while seismic response control requires a large µ. For long-period structures, the damping power and output power are not sensitive to the µ. Generally, a structure-TID system on a soft soil site absorbs more energy from a given earthquake and is capable of harvesting more energy than that on a hard soil site. This study may help develop new strategies for self-powered control and monitoring in civil structures.

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Development and Performance Analysis of Soil Flow Protector to Reduce Soft Soil Settlement Caused by Cavity Formation

Sustainability ◽

10.3390/su12093641 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3641

Author(s):

Jaewon Yoo ◽

Suwon Son ◽

Sangtae Kim

Keyword(s):

Structural Stability ◽

Field Experiments ◽

Soft Soil ◽

Field Tests ◽

Horizontal Displacement ◽

Pile Foundations ◽

Ground Settlement ◽

Small Magnitude ◽

Box Structures ◽

Soil Flow

Settlement of a relatively small magnitude occurs in box structures supported by pile foundations. However, if cavities are generated under the box structure, ground settlement can be accelerated by surrounding soil entering the cavities. In order for the structure to maintain stability for a long period of time, sustainable development to maintain the stability of the building must be continued. Preventing rapid ground settlement can lead to long-term structural stability and prevent the occurrence of life-threatening damage, thereby helping to maintain and build a sustainable urban infrastructure. Thus, in this study, a soil flow protector (SFP) that can be easily installed on the sides of the structure was developed to mitigate the aforementioned problem. Field tests and numerical analysis were performed to investigate the effect of SFP installation on structural stability and settlement reduction. After performing field experiments, it was found that SFP installation could reduce ground settlement and ground horizontal displacement. Moreover, for a 79.9-mm settlement, the safety factor was 1.315, which remained stable even when the settlement reached 345 mm. Hence, the developed SFP can be used to reduce soft ground settlement affecting box structures supported by pile foundations.

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Effect of Soil-Structure Interaction on the Seismic Response of Existing Low and Mid-Rise RC Buildings

Applied Sciences ◽

10.3390/app10238357 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8357

Author(s):

Ibrahim Oz ◽

Sevket Murat Senel ◽

Mehmet Palanci ◽

Ali Kalkan

Keyword(s):

Seismic Response ◽

Seismic Performance ◽

Soil Structure ◽

Soft Soil ◽

Soil Structure Interaction ◽

Soil Conditions ◽

Existing Buildings ◽

Structure Interaction ◽

Fixed Base ◽

New Buildings

Reconnaissance studies performed after destructive earthquakes have shown that seismic performance of existing buildings, especially constructed on weak soils, is significantly low. This situation implies the negative effects of soil-structure interaction on the seismic performance of buildings. In order to investigate these effects, 40 existing buildings from Turkey were selected and nonlinear models were constructed by considering fixed-base and stiff, moderate and soft soil conditions. Buildings designed before and after Turkish Earthquake code of 1998 were grouped as old and new buildings, respectively. Different soil conditions classified according to shear wave velocities were reflected by using substructure method. Inelastic deformation demands were obtained by using nonlinear time history analysis and 20 real acceleration records selected from major earthquakes were used. The results have shown that soil-structure interaction, especially in soft soil cases, significantly affects the seismic response of old buildings. The most significant increase in drift demands occurred in first stories and the results corresponding to fixed-base, stiff and moderate cases are closer to each other with respect to soft soil cases. Distribution of results has indicated that effect of soil-structure interaction on the seismic performance of new buildings is limited with respect to old buildings.

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