Dynamic behaviour of drystone retaining walls: shaking table scaled-down tests

Abstract

In this paper, an experimental study aiming at understanding the seismic behaviour of dry stone retaining walls is presented. Harmonic shaking table tests have been carried out on scaled-down dry-joint retaining walls involving parallelepiped bricks. It is found that a thicker wall is more resistant and that a given retaining wall is less sensitive to higher frequencies. For those higher frequencies, the walls accept larger displacements before collapsing. The displacements start to occur from a given threshold, which depends on the wall geometry but not on the frequency of the base motion. The typical toppling failure is observed for slender wall and/or low frequency inputs. For less slender walls or higher frequency inputs, walls experience local sliding failures until the complete collapse of the system. The acceleration at failure reported during the dynamic tests has been compared to the corresponding pseudo-static resistance, enabling a conservative estimate of the seismic behaviour coefficient for pseudo-static analysis of this class of retaining walls. This novel experimental dataset is aimed to serve as a validating framework for future numerical or analytical tools in the field.

Keywords:

• Earthquake engineering
• masonry
• shaking table tests
• dry stone
• seismic behaviour
• harmonic shakin
• g
• DSR
• W

Acknowledgements

The authors want to thank the French Ministry of Higher Education and Research for their financial support through the PhD scholarship. The authors want also to acknowledge the support of the technical team of the ENTPE, and particularly the help of Stéphane COINTET. The authors valued a lot the conversations had with Dr. Thiep DOANH and Dr. Denis BRANQUE (ENTPE) in relation to the behaviour of sands at low confining pressures.

Notes

1 The S28 sand had minimum and maximum void ratios equal to e_min = 0.689 and e_max = 1.031 (Combe, 1998).

2 The Transfer Function corresponds to the Fourier Transform of the response of an accelerometer divided by the Fourier Transform of the input signal (ACC2), which is herein characterised by a plateau between 3 and 70 Hz.

3 Mean void ratios and relative densities of e_loose = 0.97, $R_{D, \mathit{loose}}=19\%,$ e_dense = 0.72 and $R_{D, \mathit{dense}}=91\%$ have been found throughout the tests.

4 $A=\sqrt{2\times <{\mathrm{S}}^2(t)>}.$

Additional information

Funding

Ministère de l'Education Nationale, de l'Enseignement Supérieur et de la Recherche.