Analysis of factors influencing anti-slip pile support in tunnel landslide systems for tunnels with different burial depths

Abstract

Research on the tunnel landslide system poses significant challenges in the field of transportation engineering. Investigating the factors that influence the stress between tunnels at different depths and the effectiveness of anti-sliding pile support holds practical importance for real-world engineering applications. This study utilized indoor experiments and value engineering theory to examine the stress characteristics of four tunnel lining depths and anti-sliding piles under the influence of factors such as pile spacing, sliding zone angle, and pile type. The following conclusions were drawn: for shallow tunnel depths (10 m), the tunnel lining experiences relatively low stress, but the left wall of the lining structure undergoes greater stress due to the push of the landslide in the tunnel landslide system. With increasing tunnel depth, the bias stress ratio approaches 1, and the discrepancies between various factors gradually diminish. By comprehensively analyzing the factors impacting the support of tunnels at different depths in the tunnel landslide system, it was observed that when the tunnel depth is beyond the sliding zone (≤20 m), the H-shaped composite anti-sliding pile with 2D and 6D pile spacing exhibits a higher cost-effectiveness ratio. Conversely, when the tunnel depth is within the sliding zone (≥20 m), the combination of 6D pile spacing and round piles demonstrates greater cost-effectiveness. Utilizing the principles of value engineering theory, a comprehensive analysis was conducted to determine the optimal ratio that offers better performance at a lower cost. The conclusions derived from this study serve as a valuable reference for future construction decision-making.