复杂地质条件下大直径长螺旋钻孔压灌桩施工效率提升技术

Technologies for Improving Construction Efficiency of Large Diameter Long Spiral Bored Pressure Grouting Piles Under Complex Geological Conditions

长螺旋钻孔压灌桩施工易受地质条件、桩长、桩径、施工工艺突出等因素影响,若在复杂地质条件下施工,塌孔、钻进困难及钢筋笼难以下放等问题尤为突出。依托该类型桩基在云南某项目深厚软土、砂层中的应用,分析总结施工过程中采取的各种优化措施,结合最终成桩效果,形成深厚软土、砂层中大直径长螺旋钻孔压灌桩施工效率提升技术。

The construction of long-spiral drilled press-grouting piles is affected by such factors as geological conditions,pile length,pile diameter,construction technology,etc.In the construction of large-diameter long-spiral drilled press-grouting piles under complicated geological conditions,such problems as hole collapse,drilling difficulty as well as the difficulty in putting down steel reinforcement cage,become particularly prominent.Various optimization measures taken in the construction process were analyzed and summarized based on the application of pile foundation of the kind in deep soft soil and sand layer of a project in Yunnan province.Key technologies for improving the construction efficiency of large-diameter long-spiral drilled press-grouting piles in deep soft soil and sand layer are formed in combination with the final pile-forming effect.