CN203188224U

CN203188224U - Geomembrane bag sand blowing cofferdam

Info

Publication number: CN203188224U
Application number: CN 201320116906
Authority: CN
Inventors: 朱益平; 张旱英; 闵晓阳; 朱叶军; 罗刚; 王薇; 强家宽; 周联英
Original assignee: Zhejiang Provincial Transporation Eningeering & Construction Group Co Ltd
Current assignee: Zhejiang Provincial Transporation Eningeering & Construction Group Co Ltd
Priority date: 2013-03-15
Filing date: 2013-03-15
Publication date: 2013-09-11
Anticipated expiration: 2023-03-15

Abstract

The utility model relates to a geomembrane bag sand blowing cofferdam which comprises geomembrane bags with different lengths, and a positioning steel pipe support, wherein the bottom end of the positioning steel pipe support is inserted into the river bed surface around a bearing platform planned to be constructed, and the geomembrane bags are sequentially stacked in sequence from long to short to form an enclosed body which is closed and provided with a trapezoid transverse end face in the space inside the positioning steel pipe support. The requirement for cofferdam construction accuracy is not high, a plurality of underwater foundations can be defined and formed at a time, applicability is strong, the technology is simple, the environment is protected, the geomembrane bag sand blowing cofferdam can be widely applied to underwater structural objects which are placed where the depth of water is less than 5 meters, ripraps and boulders exist in the river bed, topographic change is large and environmental protection requirements are high.

Description

Geomembrane bag blast cofferdam

Technical field

The utility model relates to a kind of underwater foundation construction supplementary structure, particularly a kind of cofferdam of bearing platform construction under water.

Background technology

Along with expanding economy, it is more and more to cross over buildings such as rivers, island bridge harbour.The cofferdam scheme is the key of underwater foundation smooth construction.At present, the cofferdam mode of underwater foundation construction has fore shaft steel sheet-pile cofferdam, Larsen steel sheet-pile cofferdam, open caisson, builds several different methods such as cofferdam, island, precast-boxed cofferdam, but piece stone, erratic boulder geology and landform change greatly at having in the works depth bounds, the shallow water area cofferdam of the high complicated hydrologic condition of environmental requirement, above-mentioned cofferdam construction all has its limitation, exist set difficulty, have high input, long in time limit or be difficult to satisfy shortcoming such as environmental requirement.

The utility model content

The purpose of this utility model provides a kind of geomembrane bag blast cofferdam, solve the depth of water less than 5m, have aouatic structure things such as jackstone erratic boulder riverbed and landform change greatly, environmental requirement height to adopt that conventional cofferdam method existence sets difficulty, has high input, the technical problem of long in time limit, cofferdam difficult quality guarantee.

For achieving the above object, the utility model adopts following technical scheme:

A kind of geomembrane bag blast cofferdam, comprise geomembrane bag and positioning steel tube support that length differs, described positioning steel tube support bottom is inserted and is planned to build below the cushion cap riverbed face on every side, in the space of positioning steel tube internal stent, the geomembrane bag stacks gradually by from long to short order and forms the body that surrounds that horizontal end face is trapezoidal closure.

The described height H that surrounds body is that water depth+total deflection+maximum of geomembrane bag is surged+safe altitude.

The described interior hypotenuse gradient that surrounds body is 1:1.5～2; The outer hypotenuse gradient is 1:1.

The described top width B1 that surrounds body is 3m ~ 5m.

The described bottom width B2 that surrounds body surrounds the hypotenuse gradient in the height H * of body+the surround outer hypotenuse gradient of height H * of body for top width B1+.

Described positioning steel tube support passes through vertically to connect the steel pipe drawknot by vertically squeezing into steel pipe and laterally being connected some circle intersecting parallels steelframes that steel pipe is enclosed between the Internal and external cycle intersecting parallels steelframe.Distance between the intersecting parallels steelframe of two adjacent rings equals to surround the bottom width B2 of body.

The described steel pipe of vertically squeezing into inserts more than the degree of depth 2.0m that plans to build cushion cap riverbed face on every side.

Compared with prior art the utlity model has following characteristics and beneficial effect:

Less demanding, a plurality of underwater foundation of the utility model construction precision can be shaped in a cofferdam, and applicability is strong, technology is simple, and it is few to drop into main equipment, and sand can be gathered materials on the spot, low, the remarkable in economical benefits of construction cost.Simultaneously, during cofferdam demolition, only need scratch the geomembrane bag, sand can return in the Nature with current, but the film bag is natural decomposition, the construction environmental protection.

The utility model can be widely used in the depth of water less than 5m, the cofferdam of aouatic structure things such as jackstone erratic boulder riverbed and landform change greatly, environmental requirement height arranged.

Description of drawings

The utility model is described in more detail below in conjunction with accompanying drawing.

Fig. 1 is the utility model geomembrane bag blast cofferdam plan view.

Fig. 2 is the A-A sectional view of Fig. 1.

Fig. 3 is positioning steel tube support layout plan.

Fig. 4 is the B-B sectional view of Fig. 3.Fig. 5 is the C-C sectional view of Fig. 3.

Reference numeral: 1-positioning steel tube support, 1.1-vertically squeeze into steel pipe, 1.2-and vertically connect steel pipe, 1.3-and laterally connect steel pipe, 2-geomembrane bag, 3-and plan to build cushion cap, 4-precipitation well point, 5-riverbed face.

The specific embodiment

Embodiment is extremely shown in Figure 5 referring to Fig. 1, a kind of geomembrane bag blast cofferdam, comprise geomembrane bag 2 and positioning steel tube support 1 that length differs, described positioning steel tube support 1 bottom is inserted and is planned to build cushion cap 3 riverbed face on every side below 5, in positioning steel tube support 1 volume inside, geomembrane bag 2 stacks gradually by from long to short order and forms the body that surrounds that horizontal end face is trapezoidal closure.

The described top width B1 that surrounds body is 3m ~ 5m.

Described positioning steel tube support 1 passes through vertically to connect steel pipe 1.2 drawknots by vertically squeezing into steel pipe 1.1 and laterally being connected some circle intersecting parallels steelframes that steel pipe 1.3 is enclosed between the Internal and external cycle intersecting parallels steelframe.

The described steel pipe 1.1 of vertically squeezing into inserts more than the degree of depth 2.0m that plans to build cushion cap 3 riverbed face 5 on every side.

Cofferdam inner edge size=structure size+excavation of foundation pit degree of depth * is put ratio of slope 1.5 ~ 2+ foundation ditch gras generally recognized as safe distance 10 ~ 20m, outside, cofferdam size=inner edge size+weir bottom width degree.

The outer ring steel pipe of described positioning steel tube support 1 is supported with oblique steel pipe outward.

Implementation process of the present utility model is:

Step 1, the cofferdam design parameters is determined, finger is according to underwater structure size, the depth of water and riverbed geological conditions, is sidelong design parameterss such as ratio of slope, cofferdam scope and cofferdam embankment structure form, dam crest, dam bottom width degree inside and outside taking into full account the cofferdam height determined after the construction operation space, cofferdam.Described cofferdam design parameters, comprise cofferdam height, top width, bottom width and inside and outside be sidelong ratio of slope, need satisfy antiscour, anti-stable requirement.

Step 2 positions steel pipe support 1 and sets.Positioning steel tube support 1 sets :Every row's steel pipe support is vertically squeezed into the pipe level with steel pipe with 5 and is connected, laterally use greater than the wide steel pipe of bottom geotechnique bag and connect every 5m, the steel pipe level of fixing bottom geotechnique bag is connected to intersecting parallels, and outer layer pipe is aided with oblique supporting steel pipe, guarantees that whole steel pipe frame is firm.If the cofferdam levee body is filled out the heart for many row's film sackholder soil and is laid, then the inboard two row's steel pipes set up of geotechnique's bag the centre banket finish after, pull out immediately.

Step 3, layering are laid geomembrane bag 2 to the cofferdam design height: geomembrane bag 2 blasts, the underlying membrane bag fill sand draining to sand pillow and centre banket finish and fixed after, carry out the construction of last layer sand pocket again, so circulation is until top layer, top layer sand pocket width and end face form the blast cofferdam with wide.Can carry out follow-up draw water precipitation and underwater structure foundation excavation and construction by precipitation well point 4 subsequently.

Claims

1. geomembrane bag blast cofferdam, it is characterized in that: comprise geomembrane bag (2) and positioning steel tube support (1) that length differs, described positioning steel tube support (1) bottom is inserted and is planned to build below cushion cap (3) the riverbed face (5) on every side, in positioning steel tube support (1) volume inside, geomembrane bag (2) stacks gradually by from long to short order and forms the body that surrounds that horizontal end face is trapezoidal closure.

2. geomembrane bag blast according to claim 1 cofferdam, it is characterized in that: the described height H that surrounds body is that water depth+total deflection+maximum of geomembrane bag is surged+safe altitude.

3. geomembrane bag blast according to claim 1 cofferdam, it is characterized in that: the described interior hypotenuse gradient that surrounds body is 1:1.5～2; The outer hypotenuse gradient is 1:1.

4. geomembrane bag blast according to claim 1 cofferdam, it is characterized in that: the described top width B1 that surrounds body is 3m ~ 5m.

5. geomembrane bag blast according to claim 1 cofferdam is characterized in that: the described bottom width B2 that surrounds body surrounds the hypotenuse gradient in the height H * of body+the surround outer hypotenuse gradient of height H * of body for top width B1+.

6. geomembrane bag blast according to claim 1 cofferdam, it is characterized in that: described positioning steel tube support (1) passes through vertically to connect steel pipe (1.2) drawknot by vertically squeezing into steel pipe (1.1) and laterally being connected some circle intersecting parallels steelframes that steel pipe (1.3) is enclosed between the Internal and external cycle intersecting parallels steelframe.

7. geomembrane bag blast according to claim 6 cofferdam is characterized in that: the described steel pipe (1.1) of vertically squeezing into inserts and plans to build more than the degree of depth 2.0m of cushion cap (3) riverbed face (5) on every side.