Rigid gridding and pile combined foundation and its use in soft soil foundation reinforcement

Abstract

The invention discloses a rigid grid and pile composite foundation and a method applied to reinforcing soft soil foundation. The rigid grid and pile composite foundation comprises a precast pile or a cast-in-situ pile, a rigid grid structure, a tensioning net, tensioning ribs and a transitional underlayer; the precast pile or the cast-in-situ pile drives to a relatively hard ground layer from a foundation surface layer; the rigid grid structure is fixedly connected with the precast pile; the grid structure is paved with the tensioning net; the tensioning net is provided with the transitional underlayer; the transitional underlayer is tightly contacted with the foundation surface, and the thickness of the transitional underlayer is between 0.6 and 1.5 meters; and the transitional underlayer is sandy clay, gravel soil or plain concrete with crude particles. The invention organically combines the rigid grid and the pile structure, the transitional underlayer and a soft ground layer to construct a composite foundation, transfers the load to a deep layer soil body through the grid structure and a pile, can give a full play to the strength and the deformation performance of the deep layer soil body, thereby effectively improving the foundation strength and the deformation performance, and having good reinforcing effect.

Description

technical field [0001] The invention relates to a soft soil foundation reinforcement structure, in particular to a rigid grid and pile composite foundation and a method for reinforcing the soft soil foundation using the same, which is applied to the fields of construction engineering, port engineering, highway engineering, railway engineering and the like. technical background [0002] my country has a vast territory, complex and changing geological conditions, and soft soil strata of various origins are widely distributed, especially in coastal areas, Yangtze River Delta and Pearl River Delta and other economically developed areas, where marine and lacustrine silt and silty soft soil are found. With the continuous and rapid development of my country's national economy, the scale of various construction projects is constantly expanding. During the construction of construction projects, port projects, highway projects, and railway projects, we often face the problem of soft so...

AI Technical Summary

Problems solved by technology

Due to the influence of various complex geological factors and unfavorable soft soil properties, the existing various soft soil foundation reinforcement methods have certain shortcomings.

For example, the drainage consolidation method has disadvantages such as long construction period, limited improvement in strength and deformation performance, difficulty in improving secondary consolidation deformation, and large post-construction settlement. It cannot meet the foundation reinforcement requirements of bridges or culverts with strict control of settlement difference

When using the mixing pile method to strengthen soft soil foundations such as silt, there are disadvantages such as low pile body strength, large soil deformation between piles, limited depth of reinforced soft soil foundation (limited by mechanical construction capabilities), and high construction costs.

The strength of the cement mixing pile is low due to the low pH value, high moisture content, fine particles, and a lot of organic matter in soft soil such as silt; the length of the mixing pile is generally less than 20m, and the reinforcement depth is limited. In addition, the soil between the piles is not reinforced. Large deformation, so the soft soil foundation reinforced by mixing piles may still produce large settlement

Moreover, the construction cost of the mixing pile is relatively high, and it is generally not suitable for large-area soft soil foundation reinforcement.

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