Underground space development method and underpinning support system for in-situ storey addition and extension storey addition of existing building basement
By constructing replacement piles and one-to-one piles within existing buildings, combined with horizontal replacement supports, the problem of adding floors and expanding the basement of existing buildings has been solved, achieving safe and efficient underground space renovation.
Patent Information
- Application Number
- CN202511785681.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-01
- Publication Date
- 2026-01-27
AI Technical Summary
Existing technologies make it difficult to simultaneously add floors in situ and expand existing basements, especially when both above-ground and underground sections need to be preserved in situ, lacking a systematic solution.
By constructing underpinning piles and one-to-one piles within the existing building area, and combining horizontally distributed underpinning supports with the new enclosure structure, a composite functional underpinning system is formed to achieve vertical load transfer and horizontal constraint, and simultaneously complete the addition and expansion of the basement.
It enables in-situ addition of floors below and lateral expansion of existing building basements, ensuring construction safety, reducing costs, and is suitable for efficient utilization in complex geological conditions and adjacent building complexes.
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Figure CN121407604A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of urban renewal underground space development, and particularly relates to an underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement. BACKGROUND
[0002] In the construction of existing building renewal and reconstruction, the use area of the existing building can be increased, and the building use function can be improved by reconstruction and expansion, so that the organic renewal and sustainable activation of the existing building can be realized. At present, a large number of storey reconstruction of existing building underground space needs to be carried out in-situ under the condition of existing building reservation. The conventional method in the field is to first underpin the above-ground part of the existing building in-situ, and then excavate the underground space, and then connect the existing building after the new basement is completed. However, this method can only solve the problem of in-situ expansion of the existing building with only the above-ground part. For the existing building with both above-ground and underground parts, under the premise of in-situ reservation of the above-ground and underground parts, how to realize the in-situ storey addition and expansion storey addition of the basement of the existing building is still lack of systematic technical solution and mature engineering application paradigm. SUMMARY
[0003] The purpose of the present application is to provide an underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement, so as to solve the problem that the basement of the existing building is difficult to realize in-situ storey addition and expansion storey addition.
[0004] In order to solve the above technical problem, the present application provides an underground space development method for in-situ storey addition and expansion storey addition of an existing building basement, comprising:
[0005] Step S1, constructing a new enclosure structure in the existing building area and the underground space expansion area planned along the edge of the existing building area;
[0006] Step S2, constructing a plurality of underpinning piles downwardly through the old foundation bottom plate in the existing building area, so that the underpinning piles are exposed to the old foundation bottom plate, and constructing a plurality of one-column-one-pile downwardly from the ground in the underground space expansion area, wherein the one-column-one-pile comprises a structural pile and a steel column thereon;
[0007] Step S3, excavating earthwork in the underground space expansion area and sequentially constructing each layer of new beam plate to the elevation of the old foundation bottom plate, anchoring each layer of new beam plate to each layer of old beam plate of the existing building adjacent thereto, connecting each layer of new and old beam plate to the new enclosure structure through a force transmission plate belt and a top ring beam or a side ring beam, and connecting each layer of new beam plate to the steel column at the corresponding position;
[0008] Step S4, constructing horizontally distributed underpinning supports above the old foundation slab and extending horizontally to the underground space expansion area, connecting the underpinning supports with the steel columns, underpinning piles and old structure columns, and connecting the underpinning purlins outside the underpinning supports with the new envelope structure;
[0009] Step S5, excavating earthwork below the underpinning supports to the foundation excavation surface and constructing various horizontal supports, and removing the old foundation slab and old engineering piles during the excavation;
[0010] Step S6, constructing a new foundation slab, globally rebuilding each layer of basement structure below the underpinning supports from bottom to top, and removing each horizontal support, and aligning and connecting the new structure columns in the existing building area with the old structure columns;
[0011] Step S7, removing the underpinning supports, cutting off the underpinning piles above the new foundation slab, rebuilding the remaining layers of basement structure above the underpinning supports in the underground space expansion area, and completing the in-situ layer-increasing and expansion layer-increasing underground space development construction of the basement.
[0012] Further, the basement in-situ layer-increasing and expansion layer-increasing underground space development method of the existing building provided by the present application further comprises:
[0013] In step S2, a plurality of underpinning piles are constructed from the ground downward in the periphery of the existing building, and in step S4, the underpinning supports are connected with the underpinning piles in the periphery of the existing building.
[0014] Further, the basement in-situ layer-increasing and expansion layer-increasing underground space development method of the existing building provided by the present application, in step S2, before the underpinning piles are constructed, holes are formed on the old foundation slab to form slab holes, and low-clearance pile foundation equipment is used to pass through the slab holes to construct the underpinning piles downward.
[0015] Further, the basement in-situ layer-increasing and expansion layer-increasing underground space development method of the existing building provided by the present application, in step S2, the underpinning piles are distributed in a cross shape around the old structure columns with the old structure columns as the center.
[0016] Further, the basement in-situ layer-increasing and expansion layer-increasing underground space development method of the existing building provided by the present application, in step S3, when the layers of new beam plates in the underground space expansion area and the layers of old beam plates in the existing building are not at the same elevation, and when the layers of old beam plates in the existing building are not at the same elevation, the difference in height between the layers of new beam plates and old beam plates and the difference in height between the layers of old beam plates are connected by haunched structures.
[0017] Further, the basement in-situ layer-increasing and expansion layer-increasing underground space development method of the existing building provided by the present application, a top-to-bottom aligned earth outlet hole is formed on each layer of new and old beam plates, and the periphery of the hole is reinforced.
[0018] Further, the basement in-situ storey adding and expansion storey adding underground space development method of existing building provided by the present application further comprises the following steps:
[0019] In step S3, after excavating the earthwork to the elevation of the new and old beam plates of each layer, the sandwich wall beams are arranged on both sides of the top of the old structure outer wall between the upper and lower old beam plates of each layer of the existing building and are anchored and connected with the old structure columns and the old structure outer wall, a plurality of steel columns are arranged below the sandwich wall beams for temporary jacking, the first jacking construction is completed, then the old structure outer wall below the sandwich wall beams is removed, a plurality of new structure columns are constructed at the position of the old structure outer wall, the top wall and the sandwich wall beams and are anchored and connected with the lower old beam plate, finally the steel columns are removed, the second jacking construction is completed, and the vertical load of the existing building is transmitted to the old structure columns and the new structure columns through the sandwich wall beams and the top wall by the two jacking constructions.
[0020] In step S4, the jacking support is connected with the new structure columns above the jacking support.
[0021] Further, in step S4 of the basement in-situ storey adding and expansion storey adding underground space development method of existing building provided by the present application, the following steps are further included: after the jacking support system construction is completed, a plurality of new engineering piles, one column one pile, are constructed on the large-area holes in the new enclosure structure and the old foundation slab, and the soil below the old foundation slab is reinforced.
[0022] Further, in step S6 of the basement in-situ storey adding and expansion storey adding underground space development method of existing building provided by the present application, the following steps are further included: when the new foundation slab is poured and constructed, the column pile is connected with the new foundation slab through the longitudinal reinforcement at the top of the column pile, and the jacking pile is connected with the new foundation slab through the side embedded reinforcement.
[0023] In order to solve the above technical problems, the present application provides a jacking support system for basement in-situ storey adding and expansion storey adding of existing building, which comprises the following steps:
[0024] The jacking piles are a plurality of jacking piles which are constructed downward through the old foundation slab in the existing building, and the jacking piles are exposed on the old foundation slab;
[0025] The one column one pile is a plurality of one column one piles which are constructed downward from the ground in the underground space expansion area, and the one column one pile comprises a column pile and a steel column on the column pile;
[0026] The jacking support is horizontally constructed above the old foundation slab and horizontally extends to the underground space expansion area, the jacking support is connected with the steel column in the underground space expansion area, the jacking pile in the existing building area and the old structure column, and the jacking support is connected with the new enclosure structure through the peripheral jacking purlin.
[0027] Compared with the prior art, the present application has the following beneficial effects:
[0028] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the present application can balance the water and soil pressure outside the new enclosure structure by the underpinning support, thereby ensuring the safety of subsequent soil excavation, and can transfer the vertical load of the existing building with aboveground and underground buildings from the old structure column to the underpinning pile and the one-column-one-pile, thereby realizing the in-situ storey addition of the basement structure below the original basement of the existing building and the expansion storey addition of the basement structure in the underground space expansion area beside the original basement of the existing building.
[0029] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the present application can balance the water and soil pressure outside the new enclosure structure by the underpinning support, thereby ensuring the safety of subsequent soil excavation, and can transfer the vertical load of the existing building with aboveground and underground buildings from the old structure column to the underpinning pile and the one-column-one-pile, thereby realizing the in-situ storey addition of the basement structure below the original basement of the existing building and the expansion storey addition of the basement structure in the underground space expansion area beside the original basement of the existing building.
[0030] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the present application can balance the water and soil pressure outside the new enclosure structure by the underpinning support, thereby ensuring the safety of subsequent soil excavation, and can transfer the vertical load of the existing building with aboveground and underground buildings from the old structure column to the underpinning pile and the one-column-one-pile, thereby realizing the in-situ storey addition of the basement structure below the original basement of the existing building and the expansion storey addition of the basement structure in the underground space expansion area beside the original basement of the existing building.
[0031] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the present application can balance the water and soil pressure outside the new enclosure structure by the underpinning support, thereby ensuring the safety of subsequent soil excavation, and can transfer the vertical load of the existing building with aboveground and underground buildings from the old structure column to the underpinning pile and the one-column-one-pile, thereby realizing the in-situ storey addition of the basement structure below the original basement of the existing building and the expansion storey addition of the basement structure in the underground space expansion area beside the original basement of the existing building.
[0032] The application provides a basement in-situ storey increasing and expansion storey increasing underground space development method and underpinning support system of existing building, realizes in-situ static storey expansion construction of the existing building with overground building and underground building through the underpinning support system, and overcomes the technical prejudice of the in-situ expansion construction process of the existing building with overground building, that is, first jacking, then underground space development construction, and finally falling back. BRIEF DESCRIPTION OF DRAWINGS
[0033] Figure 1 is a facade structure schematic diagram of the existing building with overground building and underground building;
[0034] Figure 2 is a facade structure schematic diagram of the construction of new envelope structure, one column and one pile and underpinning column in Figure 1 ;
[0035] Figure 3 is a facade structure schematic diagram of the construction of new top layer beam plate, the connection of the new top layer beam plate and the old top layer beam plate through the force transmission plate belt and the top ring beam on the new envelope structure, and the excavation to the old foundation bottom plate in Figure 2 ;
[0036] Figure 4 is a facade structure schematic diagram of the construction of underpinning support, new engineering pile and soil body reinforcement in Figure 3 ;
[0037] Figure 5 is a facade structure schematic diagram of the excavation of the soil layer under the underpinning support to the base excavation surface and the removal of the old foundation bottom plate and the old engineering pile in Figure 4 ;
[0038] Figure 6 is a facade structure schematic diagram of the construction of new foundation bottom plate and the global reconstruction of the basement structure under the underpinning support in Figure 5 ;
[0039] Figure 7 is a facade structure schematic diagram of the removal of the underpinning support, the cutting of the underpinning pile on the upper part of the new foundation bottom plate and the global reconstruction of the basement structure in Figure 6 ;
[0040] Figure 8 is a plane structure schematic diagram of the construction of the underpinning support system in Figure 3 ;
[0041] Figure 9 is a flow chart of the basement in-situ storey increasing and expansion storey increasing underground space development method of the existing building;
[0042] shown in the drawings:
[0043] Existing building area 100, old envelope 101, old engineering pile 102, old foundation bottom plate 103, old beam plate 104, old structure column 105, old structure outer wall 106, underground building 107, aboveground building 108, ground 109, new envelope 110, underpinning pile 111, one column one pile 112, steel column 112a, column pile 112b, new beam plate 113, force transmission plate belt 114, top ring beam 115, haunch structure 116, underpinning support 117, underpinning surrounding purlin 118, soil body reinforcement 119, old foundation pile cap 120, new engineering pile 121, foundation excavation surface 122, new foundation bottom plate 123, new structure column 124, new structure outer wall 125; underground space expansion area 200. DETAILED DESCRIPTION
[0044] The present application will be described in detail below with reference to the drawings. The advantages and features of the present application will be more apparent from the following description. It should be noted that the drawings are very simplified and use non-precise proportions, only for the purpose of facilitating and clarifying the purpose of assisting in the description of the embodiments of the present application.
[0045] Please refer to Figure 9 The embodiment of the present application provides a kind of existing building basement in situ layering and expansion layer underground space development method, can include the following steps:
[0046] Step S0, please refer to Figure 1 And Figure 8 The structure of existing building area 100 aboveground building 108 and underground building 107 can be reinforced. The safety of existing building area 100 in subsequent underground space development construction is ensured by structural reinforcement. Wherein existing building area 100 includes old envelope 101, old engineering pile 102, old foundation bottom plate 103, old beam plate 104, old structure column 105, old structure outer wall 106, underground building 107, aboveground building 108, ground 109, old foundation pile cap 120. The school building is exemplified in the figure, and the structure is reinforced concrete frame structure, and the foundation is pile cap-pile-raft foundation. The pile cap is old foundation pile cap 120, the pile is old engineering pile 102, and the raft is old foundation bottom plate 103. The construction goal is to increase a layer of basement structure below the 1st floor basement of existing building, but not limited to increase a layer.
[0047] Step S1, please refer to Figure 2 And Figure 8 New envelope 110 is constructed in the periphery of existing building area 100 and underground space expansion area 200 planned along the edge. Wherein new envelope 110 includes envelope pile and water stop curtain outside. New envelope 110 can use φ800 bored pile combined with φ650 triaxial mixing pile water stop curtain outside. Figure 8The left lower corner region is the underground space expansion region 200, which forms a rectangle with the existing building region 100.
[0048] Step S2, please refer to Figure 2 A number of underpinning piles 111 are constructed downwardly through the old foundation slab 103 in the existing building region 100, a number of underpinning piles 111 can be constructed downwardly from the ground outside the existing building region 100, so that the underpinning piles 111 are exposed to the old foundation slab 103, and a number of one-column-one-pile 112 are constructed downwardly from the ground 109 in the underground space expansion region 200. One-column-one-pile 112 serves as the vertical support structure of the newly added horizontal beam slab in the region, including column pile 112b and steel column 112a thereon. Before the construction of underpinning piles 111, holes can be opened on the old foundation slab 103 to form slab holes, and low-clearance pile foundation equipment is used to construct underpinning piles 111 downwardly through the slab holes. In order to avoid interference between the underpinning piles 111 and the old engineering pile 102, and to evenly share the vertical load transmitted by the old structure column 105, the underpinning piles 111 can be distributed in a cross shape around the old foundation pile cap 120 below the old structure column 105, with the old structure column 105 as the center. The selection and quantity of underpinning piles 111 need to meet the top support requirements of the vertical bearing capacity of the existing building. The underpinning piles 111 can be cast-in-situ bored piles, micro steel pipe piles, root piles or anchor static pressure piles. The underpinning piles 111 can be φ508 static pressure steel pipe piles, the steel column 112a can be 4L140*14 steel lattice column, and the lower end is inserted into the φ800mm cast-in-situ bored pile column pile 112b to form one-column-one-pile 112.
[0049] Step S3, please refer to Figure 3In the underground space expansion area 200, excavate the earthwork and sequentially construct the new beam slab 113 to the elevation of the old foundation bottom plate 103, anchor each layer of the new beam slab 113 to each layer of the old beam slab 104 of the adjacent existing building, and connect each layer of the new and old beam slabs to the new enclosure structure 110 through the force transfer plate strip 114, the top ring beam 115, or the edge ring beam. Specifically, the top layer of the new beam slab 113 is connected to the new enclosure structure 110 through the force transfer plate strip 114 and the top ring beam 115, and the remaining layers of the new beam slab 113 are connected to the new enclosure structure 110 through the force transfer plate strip 114 and the edge ring beam. Then, the new beam slab 113 is connected to the steel column 112a. The force transfer plate strip 114 can be a reinforced concrete beam with a cross-sectional size of 700*700mm and a spacing of 1m connected by planting a steel bar along the outer side of the new and old beam slabs. When the new beam slab 113 of each layer of the underground space expansion area 200 is not at the same elevation as the old beam slab 104 of the existing building, the height difference between the new beam slab 113 and the old beam slab 104 of each layer can be connected through the haunch structure 116, and the new and old beam slabs are connected and strengthened through the haunch structure 116. When the old beam slabs 104 of each layer of the existing building are not at the same elevation, the height difference between the old beam slabs 104 can be connected through the haunch structure 116, and the old beam slabs are connected and strengthened through the haunch structure 116. The haunch structure 116 is a reinforced concrete triangular plate strip arranged along the height difference structure of the beam slab. The cross section of the triangular plate strip is a right triangle with an inclined side slope of not greater than 1:6. In order to facilitate the transportation of excavated soil, in step S3, an up-and-down aligned soil outlet hole can be formed on each layer of the new and old beam slabs, and the hole periphery is treated to be strengthened.
[0050] After excavating the earthwork to the elevation of each layer of the new and old beam slabs, the following steps can also be included:
[0051] Between the old beam slabs 104 above and below each layer of the existing building, a wall-enclosing beam is arranged along the top of the old structure outer wall 106 on both sides, and is anchored and connected to the old structure column 105 and the old structure outer wall 106. A plurality of steel columns are arranged below the wall-enclosing beam for temporary jacking. The first jacking construction is completed. Then, the old structure outer wall 106 below the wall-enclosing beam is removed, and a plurality of new structure columns 124 are constructed at the position of the old structure outer wall 106, and are anchored and connected to the top wall, the wall-enclosing beam, and the old beam slab 104 below. Finally, the steel columns are removed, and the second jacking construction is completed. Through the above two jacking constructions, the vertical load of the existing building is transmitted to the old structure column 105 and the new structure column 124 through the wall-enclosing beam and the top wall.
[0052] Step S4, please refer to Figure 4The horizontal distribution of underpinning support 117 is constructed above the old foundation slab 103 and horizontally extended to the underground space expansion area 200, connecting the underpinning support 117 with the steel column 112a, underpinning pile 111 and old structure column 105, and setting the underpinning surrounding purlin 118 outside the periphery of the underpinning support 117 to connect with the new enclosure 110. The underpinning support 117 can be connected with the new structure column 124 above it. The structure plane arrangement form of the underpinning support 117 is a longitudinal and transverse intersecting grid-shaped support bar. The new and old structure columns and steel columns 112a above the underpinning support are connected in the plane to form a whole by setting longitudinal and transverse intersecting grid-shaped support bar, the support bar is surrounded by the underpinning surrounding purlin 118 and connected with the new enclosure 110, and the support bar is anchored and connected with the underpinning pile 111 below, so that the vertical load of the existing building area 100 is transmitted to the underpinning pile 111 through the new and old structure columns and underpinning support 117, and the vertical load of the new beam slab 113 of the underground space expansion area 200 and the underpinning support 117 is transmitted to the column pile 112b through the steel column 112a. The underpinning support 117, underpinning pile 111 and one column and one pile 112 form an underpinning support system, but the complete underpinning support system also needs to include the underpinning surrounding purlin 118 and the new enclosure 110. In addition to supporting the old structure column 105 of the existing building area 100 together with the underpinning pile 111, the underpinning support system also needs to balance the pit water and soil pressure caused by the underground excavation construction. The role of the underpinning pile 111 exposed on the old foundation slab 103 is to reliably anchor and connect the underpinning support 117 on the underpinning pile 111, preferably, the top of the underpinning pile 111 is higher than the top surface of the old foundation slab 103 by not less than 500mm. The underpinning support 117 maintains a clear distance of not less than 200mm from the top surface of the old foundation slab 103, so as to facilitate the subsequent step of removing the old foundation slab 103. The old structure column 105 is roughened on the surface within the height range of the underpinning support 117, brushed with an interface agent, and then connected with the underpinning support 117 by embedding uniformly distributed anchoring steel bars. The underpinning support 117 adopts reinforced concrete support, the cross-sectional size of the underpinning support 117 can be 1000*800mm, and the cross-sectional size of the underpinning surrounding purlin 118 can be 1200*800mm.
[0053] In step S4, it can also include that after the completion of the underpinning support system construction, a large number of new engineering piles 121 and one-pile-one-column 112 can be constructed on the inside of the new enclosure 110 and the old foundation slab 103, and the new engineering piles 121 and the underpinning piles 111 are used as the permanent vertical support system of the in-situ layering basement and the lateral expansion of the existing building. The one-pile-one-column 112 here is used as the vertical support structure of the horizontal support during the construction of the in-situ layering basement structure below the existing building area 100, and the upper elevation of the steel column 112a is the height of the first horizontal support during the construction of the lower layer. In order to ensure the force transmission effect of the underpinning support system, it is necessary to avoid collision with the underpinning piles 111 during the construction of the new engineering piles 121. The soil below the old foundation slab 103 can also be reinforced. The soil can be reinforced by high-pressure rotary jet piles or cement mixing piles to form soil reinforcement 119, which can prevent soil collapse and improve the safety of foundation pit excavation. Part of the soil reinforcement 119 is shown in the figure, but not the complete soil reinforcement 119.
[0054] Step S5, please refer to Figure 5 The soil excavation is carried out below the underpinning support 117 to the base excavation surface 122 and the construction of each horizontal support, and the old foundation slab 103, the old foundation pile cap 120 and the old engineering pile 102 are removed during excavation. The old foundation slab 103 and the old foundation pile cap 120 can be removed by chiseling process, and the old engineering pile 102 can be removed by cutting process.
[0055] Among them, only the underground space expansion area 200 is excavated above the underpinning support 117, and both the existing building area 100 and the underground space expansion area 200 are excavated below the underpinning support 117, that is, full excavation is carried out in the global range. The global range refers to the existing building area 100 and the underground space expansion area 200.
[0056] Step S6, please refer to Figure 6In the global range of the existing building area 100 and the underground space expansion area 200, the new foundation bottom plate 123 is constructed to be connected with the underpinning pile 111, the column pile 112b, the new engineering pile 121 at the corresponding position, and the new foundation bottom plate 123 can also be connected with the old engineering pile 102 when the old engineering pile 102 exists. The underground structure below the underpinning support 117 is built from bottom to top, and each layer of the underground structure includes the new beam plate 113, the new structural column 124 and the new wall body constructed by the sequential construction method, and the new wall body includes the new structural inner wall and the new structural outer wall 125. The new structural column 124 in the existing building area 100 is aligned and connected to the old structural column 105. That is, the underground structure below the underpinning support 117 in the existing building area 100 and the underground space expansion area 200 is globally built, and after the old foundation bottom plate 103 and the old engineering pile 102 are removed, the new foundation bottom plate 123 is constructed, which does not affect the construction of the underground structure. When the new foundation bottom plate 123 is poured and constructed, the new engineering pile 121 is connected with the new foundation bottom plate 123 through the top, the column pile 112b is connected with the new foundation bottom plate 123 through the longitudinal reinforcement at the top, and the underpinning pile 111 is connected with the new foundation bottom plate 123 through the side embedded reinforcement, so that the underpinning pile 111, the column pile 112b and the new engineering pile 121 provide reliable vertical bearing capacity for the new foundation bottom plate 123.
[0057] Step S7, please refer to Figure 7 , the underpinning support 117 and the underpinning surrounding batten 118 are removed, the underpinning pile 111 above the new foundation bottom plate 123 is cut off, the underground structure above the underpinning support 117 in the underground space expansion area 200 is built, and the underground space development construction of the in-situ storey increase and the expansion storey increase of the basement is completed. The underground structure built in the underground space expansion area 200 includes the new structural column 124, the new structural outer wall 125 and the new structural inner wall. The vertical load of the existing building after the underground space is increased is transmitted through the underpinning pile 111, the column pile 112 and the new engineering pile 121. When the old engineering pile 102 still has a remaining part, the vertical load can also be transmitted through the old engineering pile 102. At this time, the underpinning pile 111, the column pile 112, the new engineering pile 121 and the old engineering pile 102 all serve as the pile foundation of the existing building after the underground space is increased. In the construction, the new underground first layer beam plate can be first completed to form the horizontal support, and then the underpinning support system is removed. However, when the new underground first layer beam plate cannot be constructed before the underpinning support 117 is removed due to the obstruction of the underpinning support system, the new underground first layer beam plate can be temporarily built to the next layer beam plate to form the horizontal support, the new structural column 124 is first constructed upward to be connected with the old structural column 105 above and to transfer the load, and the steel diagonal support is arranged between the inside of the new surrounding structure 110 below the underpinning surrounding batten 118 and the column foot of the next layer beam plate. Then, the underpinning support system can be removed, and the new underground first layer beam plate and the remaining underground structure can be built.
[0058] Referring to Figure 4 and Figure 8 The embodiment of the present application also provides a support system for in-situ layer increasing and expansion layer of a basement of an existing building area 100, which comprises support piles 111, column-pile 112 and support 117, wherein:
[0059] The support piles 111 are several, which are constructed downwardly through the old foundation slab 103 in the existing building area 100, and the support piles 111 are exposed to the old foundation slab 103.
[0060] The column-pile 112 is several, which is constructed downwardly from the ground in the underground space expansion area 200. The column-pile 112 comprises a column pile 112b and a steel column 112a on the column pile 112b.
[0061] The support 117 is horizontally constructed above the old foundation slab 103 and horizontally extends to the underground space expansion area 200, the support 117 is connected with the support piles 111 and the old structure column 105 of the existing building area 100, the support 117 is connected with the steel column 112a of the underground space expansion area 200, and the support 117 is connected with the new enclosure 110 through the peripheral support enclose 118.
[0062] The embodiment of the present application also provides a support system for in-situ layer increasing and expansion layer of a basement of an existing building area 100, which can further comprise:
[0063] The new enclosure 110 is constructed in the periphery of the existing building area 100 and the underground space expansion area 200 planned along the edge of the existing building area 100.
[0064] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the embodiment of the present application, by constructing underpinning piles 111 in the existing building area 100, by constructing one-column-one-pile 112 in the underground space expansion area 200, by constructing horizontally distributed underpinning supports 117 above the old foundation slab 103 and extending to the underground space expansion area 200, and by connecting the underpinning supports 117 to the new enclosure structure 110 through the underpinning purlins 118, and connecting the underpinning supports 117 to the underpinning piles 111, the old structure column 105 and the one-column-one-pile 112, so that the underpinning supports 117 can balance the water and soil pressure outside the new enclosure structure 110 to ensure the safety of subsequent soil excavation, and at the same time, the underpinning supports 117 can transfer the vertical load of the existing building area 100 with the above-ground building 108 and the underground building 107 from the old structure column to the underpinning piles 111 and the one-column-one-pile 112, thereby realizing the in-situ storey addition of the basement structure below the original basement of the existing building area 100 and the expansion storey addition of the basement structure in the underground space expansion area 200 beside the original basement of the existing building area 100.
[0065] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the embodiment of the present application, by combining the vertical load transfer and horizontal constraint functions into one through the composite function underpinning system composed of the underpinning piles 111, the one-column-one-pile 112 and the underpinning supports 117, can simultaneously serve as a vertical support system and a horizontal support structure, effectively ensuring the safety of the existing building area 100, the stability of the surrounding soil and the controllability of environmental deformation during the excavation and structural modification of the underground space.
[0066] The underground space development method and underpinning support system for in-situ storey addition and expansion storey addition of an existing building basement provided by the embodiment of the present application, by constructing the composite function underpinning system composed of the underpinning piles 111, the one-column-one-pile 112 and the underpinning supports 117 above the old foundation slab 103 in the existing building area 100 with the above-ground building 108 and the underground building 107 and extending to the underground space expansion area 200, thereby using the static underpinning method to underpin the existing building area 100 with the above-ground building 108 and the underground building 107 once, synchronously realizing the vertical storey addition below and the horizontal expansion storey addition beside, greatly reducing the cost of underground space development below the existing building area 100, and reducing the construction difficulty of in-situ storey addition of the basement.
[0067] The underground space development method and underpinning support system for in-situ addition and expansion of basements in existing buildings provided by the embodiments of the present invention address the technical bottleneck of how to achieve in-situ addition and lateral expansion of basements in existing building areas 100 with both above-ground and underground parts. It provides a complete system solution integrating underpinning, addition, and expansion, and is particularly suitable for the efficient utilization and functional upgrading of underground space in restricted scenarios such as complex geological conditions and adjacent existing building complexes.
[0068] The underground space development method and underpinning support system for in-situ addition and expansion of basement floors in existing buildings provided by the embodiments of the present invention realizes the in-situ static expansion construction of underground floors in existing buildings with above-ground buildings 108 and underground buildings 107 through the underpinning support system. It overcomes the technical bias of the in-situ expansion construction process of existing building area 100 with only above-ground buildings 108, which first lifts, then develops underground space, and then lowers the existing building area 100.
[0069] This invention is not limited to the specific embodiments described above. Obviously, the embodiments described above are only a part of the embodiments of this invention, not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of this invention are within the scope of protection of this invention. Those skilled in the art can make other modifications and variations to this invention. Therefore, if these modifications and variations of this invention fall within the scope of the claims of this invention, then this invention also intends to include these modifications and variations.
Claims
1. A method for developing underground space by adding or expanding basements in existing buildings, characterized in that... include: Step S1: Construct a new enclosure structure around the existing building area and the planned underground space expansion area along its perimeter; Step S2: In the existing building area, construct several replacement piles through the old foundation slab downwards, so that the replacement piles are exposed in the old foundation slab. In the underground space expansion area, construct several single-column piles from the ground downwards, wherein the single-column piles include column piles and steel columns on them. Step S3: Excavate earthwork in the underground space expansion area and construct new beams and slabs of each floor in sequence to the elevation of the old foundation slab. Anchor each new beam and slab to the old beams and slabs of the existing building on the adjacent side. Connect each new and old beam and slab to the new enclosure structure through force transmission plate strips and top ring beams or side ring beams. Connect each new beam and slab to the steel columns at the corresponding positions. Step S4: Construct horizontally distributed replacement supports above the old foundation slab and extend them horizontally to the underground space expansion area. Connect the replacement supports to the steel columns, replacement piles and old structural columns. Set up replacement walers around the replacement supports and connect them to the new retaining structure. Step S5: Excavate the earthwork below the underpinning support to the foundation excavation surface and construct each horizontal support. During the excavation, remove the old foundation slab and old engineering piles. Step S6: Construct the new foundation slab, rebuild the supporting structure of each basement level from bottom to top, remove all horizontal supports, and align and connect the new structural columns in the existing building area to the old structural columns. Step S7: Remove the underpinning supports, cut off the underpinning piles above the new foundation slab, and rebuild the remaining basement structures above the underpinning supports in the underground space expansion area to complete the underground space development and construction of the in-situ addition and expansion of the basement.
2. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, Also includes: In step S2, several replacement piles are constructed from the ground down around the existing building. In step S4, the replacement support is connected to the replacement piles around the existing building through the existing building.
3. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, In step S2, before constructing the replacement piles, holes are drilled in the old foundation slab to form a slab hole, and a low-clearance pile foundation equipment is used to construct the replacement piles downward through the slab hole.
4. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, In step S2, the replacement piles are distributed in a cross shape around the old structural column, with the old structural column as the center.
5. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, In step S3, when the new beams and slabs of each floor in the underground space expansion area are not at the same elevation as the old beams and slabs of each floor in the existing building, and when the old beams and slabs of each floor in the existing building are not at the same elevation, the new beams and slabs of each floor are connected by a haunch structure, and the old beams and slabs are connected by a haunch structure.
6. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, Excavation openings aligned vertically are made on the new and old beams of each layer, and the area around the openings is reinforced.
7. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, Also includes: In step S3, after excavating the earth to the elevation of the old and new beams and slabs on each floor, a partition beam is installed between the old beams and slabs on each floor of the existing building, along the top sides of the old structural exterior wall, and anchored to the old structural columns and the old structural exterior wall. Several steel columns are installed below the partition beam for temporary support, completing the first underpinning construction. Then, the old structural exterior wall below the partition beam is demolished, and several new structural columns are constructed at the location of the old structural exterior wall, anchored to the top wall and the partition beam, and finally the steel columns are demolished, completing the second underpinning construction. Through the above two underpinning constructions, the vertical load of the existing building is transferred to the old structural columns and new structural columns through the partition beam and the top wall. In step S4, the replacement support is connected to the new structural column above it.
8. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, Step S4 also includes: after the completion of the underpinning support system construction, constructing a number of new engineering piles and one-to-one piles by making large-area openings on the inner side of the new retaining structure and on the old foundation slab, as well as reinforcing the soil below the old foundation slab.
9. The method for developing underground space by adding or expanding basements in existing buildings according to claim 1, characterized in that, Step S6 also includes: when pouring the new foundation slab, connecting the column piles to the new foundation slab through their top longitudinal reinforcement, and connecting the underpinning piles to the new foundation slab through side reinforcement.
10. A support system for in-situ addition and expansion of basements in existing buildings, characterized in that, include: The replacement piles consist of several piles that are constructed downwards through the old foundation slab within the existing building, with the replacement piles protruding from the old foundation slab. One column and one pile, consisting of several columns, are constructed from the ground downwards within the underground space expansion area. The column and one pile includes the column pile and the steel column on it. The underpinning support is constructed horizontally above the old foundation slab and extends horizontally to the underground space expansion area. The underpinning support is connected to the steel columns in the underground space expansion area, the underpinning piles in the existing building area, and the old structural columns. The underpinning support is connected to the new retaining structure through the outer underpinning walers.