Experimental Evaluation on Earthquake-Resistance of Road Retaining Wall Using Gabion

Abstract

In the 2015 earthquake in Gorkha, Nepal, damaged different kinds of structures around the Kathmandu Basin. On the other hand, in mountainous areas, it was confirmed that gabion structures such as retaining walls along roads showed their high flexibility by performing their functions. In this paper, based on the results of the damage field survey on gabion retaining walls, a full-scale shake table test is conducted to evaluate the earthquake resistance of gabion retaining walls on roads, which are a common site in Nepal. The soil container used for the full-scale shake table test has the following internal dimensions: 4.0 m height, 3.1 m width, and 11.5 m depth. Earthen bank retaining walls with height of 3 m were arranged in three rows in a perpendicular direction to the cross-section, and the ground behind the retaining wall was prepared. The sinusoidal waves of 3 Hz were applied, consisting of 2 s of gradual increase, 4 s of steady part, and 2 s of gradual decrease; the input waves were provided in four stages of acceleration amplitude. Three types of gabion retaining walls were considered, i.e., vertical-type, stepwise-type and gravity-type, and 3D terrestrial laser measurement was conducted before and after shake table test of each case. Comparison of the residual deformations of the gabion retaining walls measured by 3D terrestrial laser showed that the vertical-type wall did not collapse but tilted forward after the shake teble test. A similar damage situation was confirmed by the field survey in Nepal. The other two cases suffered only slight deformation and are considered to be effective structures for application on sites. Finally, the trial wedge method was applied to the experimental results of the vertical-type of gabion retaining and useful suggestions for future earthquake-resistant design were made by comparing the active collapse angle with the positions of deformation, such as cracking which occurred in the ground behind the retaining wall after shaking. Then, the applicability of trial wedge method and its problem in the design of gabion retaining wall were shown.

Basic Study on Deformation Evaluation of Steel Wire Mesh for Rational Gabion Structure Design

“…A full-scale model experiment was conducted to verify the seismic performance and dynamic behavior of gabionbased retaining walls during an earthquake. This has been reported in detail by Nakazawa et al [6]. Based on the field survey findings, an experiment was carried out on a retaining wall model with a wall height of 3 m, using gabions with unit sizes of about 100 cm in width, height, and depth.…”

“…In this set of experiments, tests were conducted using three gabion retaining wall types shown as Cases 1 to 3, one of which consisted of the vertically upright triple-stacked gabion retaining wall common in Nepal and two which involved newly proposed gabion structures [6]. As an example here, the model specifications and test results for Case 1, which show the vertically upright triple stacks common to Nepal, are shown in Figs.…”

Model Tests on the Stability of Retaining Walls with Gabions Under Earthquake and Rainfall Conditions

“…Hara et al (2018) conducted three field surveys, in July andNovember, 2015, andNo-vember, 2016, of the damage to the gabion road retaining walls along the Araniko Highway in the mountainous regions, and have previously reported the findings in detail. The usage of gabions reported by Hara et al (2018) and Nakazawa et al (2018), shown in Fig. 1, indicates that, of the 115 locations, 49%, or approximately half, were used as road retaining walls, followed by 19% as crash barriers.…”

Evaluation of Numerical Analysis for Earthquake Resistance of Retaining Wall Using Gabions

“…Before shaing(Case1) Case1(257gal) Case2(313gal) Case3(302gal) Figure 1. Residual displacement of Gabion [8] confined pressure and 64kN/m 2 was fully considered. Figure 4 shows result of triaxial compressive test (CD test) of background and materials of support ground.…”

“…To evaluate the characteristics, and to grope more stable structures, the authors executed full-scale shake tests [7][8][9][10][11].…”