基于锤击桩-格栅体系的深厚软基处理技术研究

Study on Processing Technology of Great Depth Soft Soil Foundation Based on Hammering Piles- grille Reinforcement System

以湖南省武冈至靖州(城步)高速公路深厚软基处理为例,通过分析软基的基本性能特征,提出锤击桩-土工格栅加固体系,设计带两级承压台阶的锤击桩和普通锤击桩,并分析其加固机理和加固效果。结果表明:锤击桩挤压加固,土工格栅水平加筋,垫层增强承载力,填石约束侧向变形。带承压台阶的锤击桩承载性能优于普通锤击桩,相对于普通锤击桩而言,锚固格栅后,荷载为260kN时,沉降减少了34.51%。荷载为400kN,沉降为9mm时,能够节约工程造价9240.99元/km2,采用带承压台阶的锤击桩,合理布设土工格栅,城步高速公路的主线与支线软基处理工程节约工程造价共计649352.98元。

This article took a deep soft ground treatment works of the highway from Wu - Gang to Jing - Zhou （CHENGBU） as an example to expand a research. It put forward using hammering piles - grille system for soft base reinforcement after analyzing the basic performance characteristics of soft soil foundation. This experiment designed two kinds of hammering piles, one was belt two pressure steps the other one is common, and analyzed its reinforcement mechanism and reinforcement effects. The results showed that： Throughout the reinforcement system, hammering pile strengthening the soil, grille enhances the horizontal force, pillow top enhance the capacity, stone reducing the lateral deformation. The bearing performance of hammering piles belt two steps of pressure is better than the normal. When compared to normal hammering piles, after anchoring grille, load is 260kN, the settlement reduces 34.51%. When the load is 400kN, settlement is 9mm; the construction cost of per square kilometer can save 9240.99 Yuan. After using the hammering piles which with pressurized stairs and reasonable layout grid, the main line and branch line of soft ground treatment works of CHENGBU highway conservation the project cost totaling 649,352.98Yuan eventually.