Influence of reinforcement-arrangements on dynamic response of geogrid-reinforced foundation under repeated loading: Fid-Bau Portal

Influence of reinforcement-arrangements on dynamic response of geogrid-reinforced foundation under repeated loading

Wang, Jia-Quan / Zhang, Liang-Liang / Tang, Yi / Huang, Shi-Bin

Highlights • Influence of geogrid arrangements on the dynamic response of footing was studied. • Depth of first geogrid layer was most influence on the bearing capacity of footing. • Reasonable geogrid arrangements obviously attenuated the acceleration peak of soil. • Geogrid arrangements affected the failure mode of footing and the geogrid strain. • Suggestions on the optimal geogrid arrangements under repeated loading was proposed.

Abstract Dynamic tests were carried out on a square footing resting on unreinforced and reinforced foundation to investigate the influence of the geogrid-reinforcement arrangements on load-carrying characteristics of the footing under repeated loading. In this paper, the arrangements considered include the depth of the first geogrid layer (u), the number of geogrid layers (N) and the method of wraparound ends reinforcement. The settlement of footing, the strain of geogrid and the acceleration rate in soils were measured, and these results were analyzed in detail. The results showed that the bearing capacity of footing on reinforced foundations was at least 12% higher than that of unreinforced foundation. For the single-layer reinforced foundations, the bearing capacity first increased and then decreased with the increase of u. When u was equal to 0.6B (B = footing width), the bearing capacity was maximum, which was 21% and 15% higher than that of 0.3B and 0.9B, respectively. For the multi-layer reinforced foundations, the bearing capacity increased with increasing the N value from 1 to 3, and the maximum increase was 29%. Through analyzing the bearing capacity ratio (BCR) and the attenuation rate of acceleration (AAR), the influence of reinforcement arrangements on the bearing capacity of footing was in the order: the u value, the method of wraparound ends of reinforcement, the N value. The various reinforcement arrangements caused different dynamic responses, and the sensitivity of arrangement on acceleration responses was in the order: the N value, the method of wraparound ends of reinforcement and the u value. Additionally, it is also found that reinforcement arrangements significantly affected the geogrid strain and the failure mode of footing.