CN1687536A

CN1687536A - Construction method of subsurface excavation and layer added by using top layer of existed basement as native cover board

Info

Publication number: CN1687536A
Application number: CN 200510026522
Authority: CN
Inventors: 徐正良; 崔勤; 张中杰; 王卓瑛
Original assignee: Shanghai Urban Construction Design Research Institute Co ltd
Current assignee: Shanghai Urban Construction Design Research Institute Co ltd
Priority date: 2005-06-07
Filing date: 2005-06-07
Publication date: 2005-10-26
Anticipated expiration: 2025-06-07
Also published as: CN100348835C

Abstract

The invention provides a kind of underground digging and adding floor construction method. It makes use of the underground space as construction field, and makes the roof of present structure as natural cover board, so it divides the whole underground structure into several building sections to underground dig step by step and complete the floor addition of the underground structure. It don't need to dig widely, won't affect the normal ground traffic, and don't need to move pipelines. The project is small and can save investment. It's especially adopted to building underground to add floor in the center of the city. It's suitable for underground digging to rebuild the one floor cellar into two floor underground structure.

Description

Utilize existing basement roof to add a layer job practices as the tunneling of native cover board

Technical field

The present invention relates to the city underground construction method, particularly, relate to and utilize existing basement roof to add a layer job practices as the tunneling of native cover board.

Background technology

Reasonable development and utilize urban underground space resource is to adapt to the needs that urban modernization and urban sustainable development are built.Because the planning and the overall arrangement of the science of shortage, some have been built the underground space and can not make the best use of everything, and have caused the waste of subterranean resource, need transform.

In expanding underground space transformation, adding layer has downwards become a kind of important thinking.Traditional method is to construct again to satisfy underground two layers of space enclosing structure that excavation requires, and open cut adds layer downwards then.

Referring to Fig. 1, shown in the figure a kind of existing B1 present situation structure, this structure is found in underground store, a line west side of Shanghai Underground.As shown in the figure, this structure is to have only the underground store structure of one deck, and this market structure comprises top board 1 and base plate 2, is supported with many posts 3 between top board 1 and base plate 2; In addition, at the distolateral liner 4 that also is provided with of top board and base plate, the supporting (not shown) that is respectively equipped with other forms such as reinforced concrete sheet pile 5 or bored pile in the outside of liner 4 is with the space enclosing structure as underground structure.Usually, be not subjected to the extruding of its outside soil layer in order to guarantee underground structure, the length of sheet pile is the twice of underground structure vertical height often.

Utilize the open cut of prior art to add layer method to be, from ground, squeeze into longer sheet pile again in the existing sheet pile outside earlier the soil layer in the existing underground structure outside is reinforced, then, excavate from ground again, earlier existing underground structure is cut devastatingly, and add as required the layer the degree of depth further dig downwards, build each layer structure subsequently again.Though this method is more safe and reliable, in construction, will influence traffic above-ground and relate to relocation of services, restricted its being extensive use of at urban central zone.

Summary of the invention

Above-mentioned defective in view of prior art, the object of the present invention is to provide a kind of tunneling to add a layer job practices, utilize the underground space as the construction enveloping field, the top board that utilizes existing structure is as native cover board, the layer that adds of underground structure is finished in downward progressively tunneling, need not carry out open-cut, do not influence normal traffic above-ground, need not to carry out relocation of services, project scale is little, reduce investment outlay, be specially adapted to undergroundly in the down town add layer construction, be particularly useful for the tunneling of one deck basement is transformed into underground two-layer structure.

Description of drawings

Fig. 1 is existing B1 present situation structural representation;

Fig. 2 is that tunneling of the present invention adds a layer job practices construction sequence schematic diagram;

Fig. 3 is the schematic diagram of next step shown in Figure 2;

Fig. 4 is the schematic diagram of next step shown in Figure 3;

Fig. 5 adopts the inventive method to cut the schematic diagram of former underground structure base plate;

Fig. 6 adopts the inventive method to build the schematic diagram of new base plate; And

Fig. 7 is the underground structure schematic diagram that adopts the inventive method construction to finish.

The specific embodiment

Below promptly adding floor with underground store, a line west side of Shanghai Underground is example, describes method of the present invention in detail.

As shown in Figure 1, this structure is to have only the underground store structure of one deck, and this market structure comprises top board 1 and base plate 2, is supported with many local posts 3 between top board 1 and base plate 2; In addition, the distolateral liner 4 that also is provided with at top board and base plate is respectively equipped with reinforced concrete sheet pile 5 with the space enclosing structure as underground structure in the outside of liner 4.Usually, be not subjected to the extruding of its outside soil layer in order to guarantee underground structure, the length of sheet pile is the twice of underground structure vertical height often.

Need to prove, because existing basement area is often bigger, can adopt segmentation to construct, following explanation is an example with one section construction wherein, because the job practices of each construction section is identical, so no longer construction is repeated in this description to each section.

As shown in Figure 2, job practices of the present invention at first is that the soil body of basement bottom board 2 belows is reinforced.Particularly, rotary churning pile 6 is set, then the soil body A between the rotary churning pile is reinforced in sheet pile 5 inboards of original structure space enclosing structure.Because rotary churning pile has the construction machinery dexterity, the tangible characteristics of consolidation effect, so the present invention adopts rotary churning pile to carry out the full hall of ground to reinforce, suitably strengthen at the regional A ' reinforcement depth near the basement space enclosing structure.The unconfined compression strength of reinforcing the back soil body is not less than 1.2MPa.

Preferably, H shaped steel 7 is inserted formation retaining structure in the rotary churning pile 6.Owing to be subjected to the restriction of former basement floor height, H shaped steel sectional inserts and is welded into integral body, and H shaped steel is also no longer extracted recovery after all construction is finished.

Referring to shown in Figure 3, there is shown next construction sequence through step shown in Figure 2.Particularly, static pressed pile 8 is squeezed into the structure base plate 2 times, static pressed pile 8 generally can adopt pile for prestressed pipe, lattice column 9 is set on it realizes the underpining of original structure roof with this, for the construction of tunneling downwards creates conditions.Because the change of post dictyosome system is still needed top board 1 is carried out carbon fiber reinforcement processing or overlapping layers consolidation process.Carbon fiber reinforcement layer or superimposed back-up coat 10 are as shown in Figure 4.

Referring to shown in Figure 4, Fig. 4 shows through the next step after Fig. 3 construction sequence.Particularly, at first, the substep piecemeal cuts the local post 3 of original structure, base plate 2.As shown in Figure 5, there is shown the substep piecemeal and cut the mode of base plate, that is, base plate is divided into several suitable cut respectively after cutting the district.

Again referring to shown in Figure 4, after the substep piecemeal cuts local post 3 of original structure and base plate 2, soil body A after excavation is reinforced downwards, when reaching regulation absolute altitude place, horizontal steel bracing frame 11 is set between the rotary churning pile 6 of both sides, continues then to excavate until the required degree of depth downwards and finish building of new base plate 2 '.

Particularly as shown in Figure 6, there is shown the mode of substep block placement new base plate, that is, build respectively after base plate is divided into several suitable pouring areas, and then the surplus part of institute is built.

Since do not have the soil body that ground construction enveloping field, this stage excavate out directly vertical transport go out ground, and can adopt two kinds of unearthed modes: unearthed by contiguous genuine level transportation; Set out Tu Jing in the zone that does not influence traffic, after the transportation of underground space level, vertically be unearthed.

Referring to shown in Figure 7, there is shown through the next step after Fig. 4 construction sequence and reach the adding storey structure state of finally finishing.Particularly, new base plate 2 ' build finish after, in time build liner 12, and build first floor structure base plate 2 again, this base plate can be identical with original structure base plate position.So far, as shown in Figure 7,, finished transformation, promptly formed underground two layers structure the structure of original B1 through foregoing construction sequence.Subsequently, proceed the construction of next active section, entirely descend structure adding layer until finishing.

Can understand from the above description, adopt method tunneling of the present invention to add a layer job practices, utilize the underground space as the construction enveloping field, the top board that utilizes existing structure is as native cover board, the layer that adds of underground structure is finished in downward progressively tunneling, need not carry out open-cut, not influence normal traffic above-ground, need not to carry out relocation of services, project scale is little, reduce investment outlay, be specially adapted to undergroundly in the down town add layer construction, be particularly useful for the tunneling of one deck basement is transformed into underground two-layer structure.

Claims

1. one kind is utilized existing basement roof to add a layer job practices as the tunneling of native cover board, wherein, existing underground structure comprises top board and base plate, between described top board and described base plate, be supported with many local posts, at the distolateral liner that also is provided with of described top board and described base plate, the supporting that is respectively equipped with other patterns such as reinforced concrete sheet pile or boring grout in the outside of described liner is with the space enclosing structure as underground structure; It is characterized in that whole underground structure is divided into a plurality of construction sections adds layer, the job practices of described each construction section may further comprise the steps:

1) soil body of the described floor below of existing underground structure is reinforced; Sheet pile inboard at existing underground structure is provided with rotary churning pile, then the soil body between the rotary churning pile is reinforced, and the unconfined compression strength of reinforcing the back soil body is not less than 1.2MPa;

2) the described top board to existing structure underpins; In through the soil body of reinforcing and under the described base plate at existing structure, squeeze into static pressed pile, and on described static pressed pile, lattice column is set;

3) the substep piecemeal cuts the described local post of existing structure, described base plate;

4) soil body after excavation is reinforced downwards when reaching regulation absolute altitude place, is provided with horizontal steel bracing frame between the rotary churning pile of both sides, continue downward excavation then until the required degree of depth;

5) the new base plate of substep block placement;

6) build first floor structure base plate;

7) repeat above step 3) to 6) to carry out the construction of next section, until the storey-adding reconstruction of finishing whole underground structure.

2. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 1), suitably strengthens at the regional reinforcement depth near the space enclosing structure that has underground structure now.

3. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 1), H shaped steel is inserted in the described rotary churning pile form retaining structure.

4. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 2) in, described static pressed pile is a pile for prestressed pipe.

5. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 2) in, described top board is carried out carbon fiber reinforcement handle to form a carbon fiber reinforcement layer.

6. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 2) in, described top board is carried out the overlapping layers consolidation process to form a superimposed back-up coat.

7. tunneling as claimed in claim 1 adds a layer job practices, it is characterized in that, in described step 6), described first floor structure base plate is identical with the described base plate position of existing structure.