Study on Seismic Response in Deeply Deposited Saturated Liquefiable Soil Reinforced by Using Subarea Long-Short Gravel Piles

Junding Liu,Ze Li,Rongjian Li,Shibin Zhang,Weishi Bai

doi:10.3390/app112311271

Abstract

To avoid large deformation, resulting from liquefaction, in inclined and deeply deposited liquefiable soil, it is necessary to design economical and reasonable reinforcement schemes. A reinforcement scheme employing subarea long-short gravel piles was proposed, and it was successfully applied in the embankment construction of the Aksu-kashgar highway. To reveal its underlying mechanism and effect on the seismic performance of the highway, the dynamic responses of natural foundation and two kinds of reinforced foundations were analyzed and compared under this scheme, using the program FEMEPDYN. Results showed that both the seismic subsidence and the excess pore pressure ratios were far less in the foundation reinforced with isometric gravel piles and in the foundation reinforced with subarea long-short gravel piles, compared with that in natural foundation. Therefore, the potential hazards of liquefaction were overcome in these two kinds of reinforced foundations. Furthermore, it was obvious that the shielding region only formed within the foundation reinforced with subarea long-short gravel piles. With the shielding effect, the proposed reinforcement scheme employing subarea long-short gravel piles not only eliminated liquefaction in deeply deposited liquefiable soil, but it also demonstrated an outstanding advantage in that the total length of gravel piles used was greatly reduced compared to the total length in the isometric gravel piles scheme and the interphase long-short gravel piles.

Highlights

The large deformation, caused by earthquake liquefaction, will endanger the stability of nearby rivers and the environment of formation slopes
In the later period of the earthquake, the subsidence distribution of the natural founIn the later period of the earthquake, the subsidence distribution of the natural foundation, foundation reinforced with isometric gravel piles, and foundation reinforced with dation, foundation reinforced with isometric gravel piles, and foundation reinforced with subarea long-short gravel piles are as shown in Figure 8a–c, respectively
Twenty seconds into an earthquake, the dynamic excess pore water pressure distriTwenty seconds into anfoundation earthquake, the dynamic excess pore water pressure disbution in natural foundation, reinforced with isometric gravel piles, and fountribution in natural foundation, foundation reinforced with isometric gravel piles, and dation reinforced with subarea long-short gravel piles in the deeply deposited saturated foundation reinforced with subarea long-short gravel piles in the deeply deposited satuliquefiable soil are shown in Figure 9a–c, respectively

Summary

Introduction

The large deformation, caused by earthquake liquefaction, will endanger the stability of nearby rivers and the environment of formation slopes. Liquefaction caused by earthquakes often leads to the loss of bearing capacity of the foundation and endangers the safety of structures built on the liquefiable soil (Xu et al [1]). Werner et al [5] reported seismic damage to the port structure of Port-Au-Prince during the 2010 Haiti earthquake and pointed out that large-scale liquefaction and lateral spreading of soil near the port caused different degrees of lateral movement of bridge pile foundations and abutments. Zhou et al [7] studied liquefaction cases in the Wenchuan Earthquake in China in 2008 and reported damage by seismic liquefaction and lateral displacement of pile foundation in Yingxiu Town.

Methods

Results

Discussion

Conclusion