CN-122014019-A - Underground space vertical extension construction method and structure

CN122014019ACN 122014019 ACN122014019 ACN 122014019ACN-122014019-A

Abstract

The invention relates to a vertical extension construction method and structure of an underground space, comprising a compensation pile, an anchoring assembly, a truss, a top support system and a newly added foundation, wherein the compensation pile is vertically arranged on the outer side of an existing building outer wall projection line, the anchoring assembly is fixed around the middle upper part of an existing structural column in an original underground layer to form a high-position load stress node, the inner end of the truss is fixedly connected with the anchoring assembly, the outer end of the truss passes through an existing side wall of the original underground layer and is fixed on the pile top of the compensation pile to form a suspension support system, and the newly added foundation is arranged below an extension space below the original underground layer to form a stress foundation of the extension structure. The invention has smart design, realizes the depth expansion of the underground space, has clear stress, controllable construction, reliable combination of new and old structures and strong applicability.

Inventors

CHEN LU
GAO YUFEN
ZHANG ZHONGSHAN
XU HONGJIE
HUANG LIYUAN
JIAO ANLIANG
LI JIANAN

Assignees

中国建筑第七工程局有限公司
阳光学院

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (10)

1. A vertical extension construction structure of an underground space is characterized by comprising compensation piles, an anchoring assembly, trusses, a top support system and a newly-increased foundation, wherein the compensation piles are vertically arranged on the outer sides of projection lines of the outer walls of existing buildings, the bottoms of the compensation piles are embedded into underground soil bearing layers, the anchoring assembly is fixed around the middle upper parts of existing structural columns in an original underground layer to form high-position load bearing nodes, the trusses are transversely arranged, the inner ends of the trusses are fixedly connected with the anchoring assembly, the outer ends of the trusses penetrate through existing side walls of the original underground layer and are fixed to pile tops of the compensation piles, the top support system comprises jacks arranged at the bottoms of the inner ends of the trusses and arranged at the tops of the compensation piles, the inner side jacks are supported at the left end and the right end of the trusses to form a suspension support system, and the newly-increased foundation is arranged below an original underground layer of building space to form a stress foundation of the extension structure.
2. The vertical building construction structure of underground space of claim 1, wherein the anchor assembly comprises a friction lining, a shell and a bearing support, wherein the two sets of shells are buckled and combined and enclosed and fixed on the existing structural column, the friction lining is adapted and fixed on the inner side of the shell, the friction lining is attached to the column of the existing structural column when the shells are fixed together, and the bearing support is welded and fixed on the outer side wall of the shell and is fixedly connected with the truss.
3. The underground space vertical extension construction structure according to claim 2, wherein the outer wall of the shell is uniformly fixed with a plurality of reinforcing ribs.
4. The underground space vertical extension construction structure according to claim 1, wherein the existing side wall is provided with a wall penetrating hole, a steel wall penetrating sleeve box is arranged in the hole, and the truss penetrates through the sleeve box and is in a spaced sleeved relation with the sleeve box, so that truss load does not directly act on the existing side wall.
5. The underground space vertical extension construction structure according to claim 4, wherein the periphery of the truss open area of the side wall is reinforced by carbon fiber cloth.
6. The vertical extension construction structure of underground space according to claim 1, wherein the newly added foundation comprises a new pile foundation arranged at the bottom of the extension space, a new bearing platform arranged at the top of the new pile foundation, and a new bearing column connecting the new bearing platform and the cutting section of the existing structural column.
7. The underground space vertical extension construction structure according to claim 6, wherein the new bearing column corresponds to the existing structural column in the same axis, and the new bearing column and the existing structural column are connected in a penetrating manner through the longitudinal steel bars and are integrally poured by high-strength grouting materials to form an integrated vertical bearing member.
8. A method for constructing a vertical extension of an underground space, which is applied to the vertical extension construction structure of the underground space according to any one of the claims 1 to 7, and is characterized by comprising the following steps: Step 1, setting out a compensation pile position outside a projection line of an existing building outer wall, and constructing a compensation pile to form an external rigid supporting foundation; Installing an anchoring assembly at the upper middle part of the existing structural column, so that the anchoring assembly is tightly meshed with the existing structural column to form a high-position load connecting pipe node; step 3, constructing a steel truss, wherein one end of the truss is rigidly connected with the anchoring assembly, and the other end of the truss transversely passes through the side wall and is supported on the pile top of the compensation pile so as to construct a suspension system, so that load is transmitted to an external compensation pile through the truss; step 4, installing jacks on the inner side of the truss and the pile tops of the compensation piles, and controlling the inner side jacks and the outer side jacks to synchronously and stepwise jack up to realize the conversion of a load path from the column bottom bearing of the existing structural column to the high-position suspension bearing; Step 5, after the suspension system is stable, cutting the column feet of the existing structure in the extension area, partially sealing the plate blocks of the original bottom plate and discarding the existing pile foundations; step 6, excavating earthwork from top to bottom in a layered and segmented manner until reaching the elevation of the foundation of the building, and then newly adding a structure for construction, wherein the construction comprises the construction of a new pile foundation, a new bearing platform and a new bottom plate, and the construction of a permanent bottom stress system; Step 7, constructing a new bearing column, and pouring the new bearing column and the existing structural column and a new bearing platform to form an integrated vertical bearing member; Step 8, taking a new pile foundation, a new bearing platform and a new bearing column as supports, and reversely constructing a new structure beam slab, a side wall and a matched waterproof electromechanical pre-buried project of an underground widen layer from bottom to top; And 9, after the strength of the newly-increased structure reaches the standard, controlling the jack to synchronously step down, transferring the upper load to a permanent stress system, then dismantling the temporary suspension structure, and plugging the soil taking port to finish the vertical extension of the underground space.
9. The method of claim 8, wherein in step 3, the fiber grating sensor is embedded in the surface of the existing structural column, and in the lifting process of step 4 and the load transferring process of step 9, the change of structural stress and displacement is monitored in real time by the fiber grating sensor, and the lifting amount or the dropping amount of the jack is adjusted in real time according to the monitored data.
10. The method of constructing a vertical extension of an underground space according to claim 8, wherein in step 4, the jacks at both ends of the truss are controlled to synchronously and stepwise lift, and the lifting amount is adjusted in real time to balance the inward moment and the outward moment of the truss until the residual counter force of the column foot of the existing structure is reduced to 5% -8% of the initial value and the displacement is stable.

Description

Underground space vertical extension construction method and structure Technical Field The invention relates to the technical field of construction of underground space of constructional engineering, in particular to a vertical extension construction method and structure of underground space. Background With the continuous gathering of urban population of various centers in China, the existing ground building capacity is difficult to meet the production and living demands of residents, and commercial and civil and municipal facilities such as markets, subway stations, comprehensive transportation hubs and the like are gradually expanded to underground deep space. However, a large number of existing buildings are not planned in an overall way for the utilization of long-term underground space in the initial construction stage, the number of the original underground floors is small, the space is narrow, and the existing buildings are not matched with the current use requirements. The existing building underground expansion mainly adopts a demolishing reconstruction or horizontal extension mode, but has the problems of high demolishing reconstruction cost, long construction period, complete loss of the use function of the building during construction, large occupation area of the horizontal widen, complex connection nodes of new and old structures, large construction disturbance and the like no matter in open excavation or hidden excavation. The patent CN118793298A discloses an underground range-increasing method of the existing building in operation, which adopts the scheme that the residual bearing capacity of the existing pile foundation is utilized to excavate and form a construction space below the existing foundation, a underpinning pile foundation is constructed, an upper connecting column is lengthened, a hydraulic jack is arranged between a basement conversion top plate and the existing foundation, the connection between the existing pile foundation and the foundation is disconnected through the lifting force of the jack, the deformation of the building is regulated according to monitoring data, and finally the underground layer-increasing construction of the existing building is realized. The technical scheme is characterized in that a jack is arranged on a conversion top plate in the actual construction, so that bending deflection deformation is generated after the conversion top plate is loaded, the deflection deformation is directly and downwards overlapped on the jack, the uncontrollable initial sinking of an existing building is generated during load conversion, moreover, the jack is required to be arranged in a narrow gap between the existing foundation and the newly-increased conversion top plate, underpinning equipment, hydraulic pipelines and the like are densely distributed above an excavation area, the construction space is directly limited due to the arrangement, the construction efficiency of a plurality of layers of downwards-falling widen layers is directly limited, in addition, the jack can be used for adjusting the elevation of the existing building in real time according to settlement monitoring data, a passive compensation mechanism of the acquired building is adopted, and the active balance cannot be performed on the uneven deformation of a large-span supporting member due to complex stratum stress, so that response hysteresis and adjustment limitation exist to a certain extent. Based on the above, it is necessary to study a method and structure for constructing a vertical extension of an underground space. Disclosure of Invention In view of the above, an object of the present invention is to provide a method and a structure for constructing a vertical extension of an underground space, which are used for effectively solving the problems of the prior art. The technical scheme includes that the underground space vertical extension construction structure comprises compensation piles, an anchoring assembly, trusses, a shoring supporting system and a newly-increased foundation, wherein the compensation piles are vertically arranged on the outer sides of projection lines of external walls of existing buildings, pile bottoms of the compensation piles are embedded into underground soil bearing layers, the anchoring assembly is fixed around the middle upper parts of the existing structural columns in an original underground layer to form high-position load bearing nodes, the trusses are transversely arranged, inner ends of the trusses are fixedly connected with the anchoring assembly, the outer ends of the trusses penetrate through the existing side walls of the original underground layer and are fixed to pile tops of the compensation piles, the shoring supporting system comprises jacks arranged at the bottoms of the inner ends of the trusses and at the tops of the compensation piles, the inner side jacks are supported at the left end and the right end of the trusses to form suspension su