Experimental Research On the Performance of a Novel Geo-Filament Anchor For An Earthen Architectural Site

Abstract

An efficient anchoring method, explicitly developed for small sliders, has hitherto been missing in the practice of earthen architecture conservation. Furthermore, anchoring performance studies conducted so far, have failed to fully take into account the soil characteristics of certain targets. To address these concerns, the conservation project conceived for the Gaochang Ruins, Turpan, in China, was selected as the testing ground to design a novel Geotechnical Filament Anchor (GFA) for reinforcing small sliders in the earthen historical ramparts. In-situ experiments were conducted for evaluating six parameters—anchoring length (L), GF thickness (H), bore diameter (D), grouting strength (S), GFA surface status (R), and inclination angle (A). These parameters were varied in order to determine the effect they produce on anchoring performance, as demonstrated by the indicators, including tensile strength, destruction mode, load displacement (P-S) relation, and strain (ζ-L) distribution characteristics of the novel GFA. Data acquired from the experiments, in combination with the conservation specifics of earthen architectural sites, anchoring performance, and safety reserve, were further employed to introduce a calculation formula for computing the designed force value (N) through L. A simplified model depicting the shear stress distribution of the anchoring system under N was devised by extracting the strain distribution data with respect to the GF-grouting interface. Taking into account the soil properties of the above-mentioned site, the shear stress diffusion coefficient (α) was conceptualized, the formula for the shear strength of the grouting material was devised, and the tolerable ranges of L, D, H, R, and S were determined. Thus, a feasible anchoring method for small sliders used in earthen architectural sites is proposed, and validated by strong and reliable experimental and theoretical groundwork.