Construction method for composite foundation on soft soil stratum

A composite foundation and construction method technology, applied in soil protection, infrastructure engineering, construction and other directions, can solve the problems of high construction cost, large construction noise, large environmental impact, etc., to achieve good water permeability and reduce investment costs.

Inactive Publication Date: 2014-08-06
丁思华 +1
View PDF4 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, in the field of geotechnical engineering, for the construction technology of weak foundation replacement, the commonly used methods include vacuum compaction and compaction method, surcharge preloading, deep mixing, dynamic compaction method, vibrating gravel pile, etc. However, these The method generally has low bearing capacity, large settlement, long construction period, large environmental impact, difficult construction quality control, high construction cost, unsatisfactory treatment effect, insufficient replacement depth and other related unfavorable factors
For example: Vacuum compaction compaction method and surcharge preloading method are passive treatment methods, and the construction period is very long, especially for soils with high saturation, low permeability, thixotropy, soft plastic or flow plastic state , the treatment effect of these construction methods is limited; the disadvantage of deep mixing piles is that

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Construction method for composite foundation on soft soil stratum
  • Construction method for composite foundation on soft soil stratum
  • Construction method for composite foundation on soft soil stratum

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] An industrial warehouse with an area of ​​20,000m 2 , single-layer light steel structure. Geological conditions: silt 18-20m below the natural ground, characteristic value of foundation soil bearing capacity f ak =40kPa,E s =1.44MPa; the bearing layer is silt soil, and the characteristic value of bearing capacity of foundation soil f ak =190kPa,E s = 10.49MPa. The characteristic value f of the bearing capacity of the foundation soil below the floor is required by the design ak = 100kPa.

[0044] The original plan: set up concrete caps of 6*6 meters, set 4 Φ600 prestressed pipe piles under each cap, the pile length is 30m, and set primary and secondary beams and 180 thick reinforced concrete floor slabs on the caps.

[0045] In this plan, Φ1200~1500~2500 reinforcements are used to arrange the reinforcements, the pile length is 18~20m, and the piles are arranged in an equilateral triangle; the triangle center is set to Φ1200, and the pile length is 8m, and one reinf...

Embodiment 2

[0047] A certain 50,000 m 3 Oil tank foundation, diameter Φ60m. Geological conditions: silty clay 20m below the natural ground, no hard crust, characteristic value of foundation soil bearing capacity f ak =45kPa,E s =3.14MPa; the bearing layer is silty clay, and the characteristic value of bearing capacity of foundation soil f ak =180kPa, E s = 3.62MPa. The characteristic value f of the bearing capacity of the foundation soil below the foundation is required by the design ak = 250kPa.

[0048] The original plan: According to Φ600 prestressed pipe piles, the pile length is 36m, and the piles are spread all over the house.

[0049] In this plan, Φ1800~2500 reinforcements are used, and piles are spread all over the house; reinforcements are arranged between tanks and around them according to Φ1500-1500, and the pile length is 20m. After the construction is completed, it will be replaced by dynamic tamping; the processing results have been tested, and the characteristic val...

Embodiment 3

[0051] Geological conditions of an airport runway: There are 8-15m thick clayey silts under the plain fill, 5-8m thick collapsible loess under this layer, and the bearing layer is a relatively good soil layer. This scheme first adopts the method of introducing holes, then back-presses the casing above the bearing layer, feeds and rams and fills solid materials, and after replacing the collapsible loess layer, lifts the casing while feeding and tamping, and then inserts the hole Partially compacted. This scheme has the best effect in dealing with the sandwich layer of soft soil foundation.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Pile lengthaaaaaaaaaa
Carrying capacityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a construction method for a composite foundation on a soft soil stratum. The main equipments relating to the construction method are a pile machine, a column hammer (2) and a pile casing (1), wherein feeding openings (3) are formed in the casing wall of the pile casing (1). Besides the preparatory processes such as staking, layout, and placing the pile machine in a proper place, the construction method further comprises the following steps: dropping the hammer repeatedly to beat a soft soil layer until the column hammer (2) is in contact with a bearing stratum (9) to form a pile hole (4); feeding and tamping repeatedly to form a single discrete pile (6); constructing corresponding multi-single discrete piles on multi-pile positions to form discrete cluster piles; treating the discrete cluster piles according to a post process to form the complete composite foundation; the solid material is an artificial compound composed by the inorganic solid material and original soil. Under the action of tamping energy, the dropped solid material not only is tamped, but also is extruded and expanded around; the soil mass intensity around the pile is also transformed when the pile is formed, and a pile-soil common stressing body is formed so as to form a composite foundation of which large area of the soft soil foundation is wholly strengthened and the displacement ratio is higher.

Description

technical field [0001] The invention relates to a soft soil foundation treatment technology for geotechnical engineering, in particular to a construction method for replacement treatment on soft soil layers such as construction of industrial or civil buildings and municipal engineering in areas along rivers, lakes and seas. The composite foundation construction method using loose piles as reinforcements on the stratum is suitable for the replacement treatment of large-area and deeply buried soft soil. Background technique [0002] To build a large area of ​​fixed facilities or ports, roads, etc. on silt or silt soft soil foundation, it is necessary to carry out large-scale foundation reinforcement treatment to prevent accidents such as foundation settlement and subsidence. At present, in the field of geotechnical engineering, for the construction technology of weak foundation replacement, the commonly used methods include vacuum compaction and compaction method, surcharge pr...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): E02D3/08
Inventor 丁思华丁锦良
Owner 丁思华
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products