Suggestions for Anti-Floating Design of Basement Structures in Weakly Permeable Layers

Abstract

This study focuses on common anti-floating issues associated with underground structures in weakly permeable geological conditions. Based on a real engineering case, the research systematically analyzes the primary causes of buoyancy failure by examining the disconnect between design and construction phases. The findings indicate that insufficient consideration is often given to the configuration of anchor rods, waterproofing measures, backfill compaction, and surface drainage systems in current anti-floating designs. These oversights can lead to abnormal rises in groundwater levels during extreme rainfall events or in later stages of construction, ultimately resulting in structural uplift.The study further investigates the disturbance effects of underground structures on groundwater seepage fields, highlighting the necessity of accounting for the coupled influence of structural dimensions, embedment depth, and soil permeability in anti-floating design. This is essential to ensure long-term stability and safety under service conditions. In addition, common construction defects related to prestressed anchors are summarized, and practical recommendations are proposed to enhance the integrity and durability of anti-floating systems. The outcomes of this research provide both theoretical reference and practical guidance for anti-floating engineering of underground structures in similar geological settings.