Evaluation on anchoring force demands of typical damaged rammed earth city wall sites under earthquake

• Published in: Arabian journal of geosciences 2021-04, Vol.14 (8), Article 692
• Main Authors: Lu, Wei, Zhao, Dong, Li, Dong-bo, Jiang, Hao-tian
• Format: Article
• Language: English
• Subjects: Acceleration; Anchorages; Anchoring; Cantilever beams; Cracking (fracturing); Earth and Environmental Science; Earth science; Earth Sciences; Earthquake damage; Earthquakes; Energy conversion; Failure analysis; Failure modes; Modes; Original Paper; Rammed earth; Seismic activity; Soil; Soils; Stability; Stability analysis
• ISSN: 1866-7511; 1866-7538
• DOI: 10.1007/s12517-021-06889-8

Suspended and high-rise soil blocks of damaged rammed earth city wall generally reinforced by anchorage technology. According to the cultural relic protection principle, the primary task is to evaluate the anchoring force demands. Based on the analysis of formation mechanism and failure modes of dangerous soil blocks under earthquake, the disaster formation process caused by the cumulative section cracking is revealed, and the basic conditions for maintaining stability of the anchored city walls are analyzed. Then, a simplified mechanical model of cantilever beam was proposed for two typical failure modes. With the combination of energy conversion principle, the quasi-static method was used to derive the calculation formulas for the critical horizontal earthquake acceleration and the anchoring force demands. The advantage and disadvantage factors for the stability of sites were clarified with corresponding anchorage design suggestions. Finally, the influence of earthquake acceleration and existing cracks on anchoring force demands and critical earthquake acceleration are discussed through practical cases. The results showed that the optimal anchoring angles of sites under different failure modes are quite different; the increase of earthquake acceleration and cumulative cracking of the sections will increase the anchoring force demands significantly.