A support system and construction method for basement layering reconstruction of existing buildings

Abstract

The present application relates to a kind of supporting system and construction method for basement storey increasing reconstruction of existing building, and multiple groups of permanent pile are advanced and set in deep place below basement ground and around original structure column, temporary support pile is connected at the top of permanent pile, load-bearing pile cap with self-locking structure is arranged at the top end of temporary support pile, jacking seat containing hydraulic jack and guide cylinder is arranged above pile cap, conical hoop frame with small top and large bottom is arranged outside original structure column, slider in hoop frame is linked with guide cylinder by hinged link, slider can be driven to climb and fold when hydraulic jack jacks up, realize that jacking force and hug force are synchronous increment, cooperate with adjustable cross brace between rigid locking structure and pile, improve overall stability and lateral displacement resistance, the present application is strong in linkage, convenient to disassemble and assemble, safe and reliable, adapt to various basement storey increasing reconstruction conditions;Solve the problem that the jacking of existing underpinning structure and the clamping action of hoop are not synchronous, the clamping stability is poor, easy to slip and jam, easy to damage original structure.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology and relates to a support system and construction method for adding floors to existing basements. Background Technology

[0002] In the renovation project of adding floors to the basement of an existing building, it is necessary to temporarily support the upper building structure to offset the stress changes caused by earthwork excavation and structural demolition, and to ensure the stability and safety of the original building structure throughout the construction process. At present, the mainstream support structure in the industry mostly adopts a combination structure of fixed steel support, ordinary jack support and simple clamps. It can only achieve simple vertical support, and has obvious defects in adaptability and linkage, which makes it difficult to meet the needs of refined and high-safety basement renovation construction.

[0003] In traditional support systems, the vertical jacking structure and the column clamping structure are independent of each other. The jacking operation and the column clamping operation are carried out step by step without any linkage. During the jacking process, the simple clamps cannot adaptively adjust the clamping force according to the changes in the jacking force, which can easily lead to loosening and slippage of the column clamps. This can cause the upper structure to shift under stress, resulting in safety hazards such as minor building settlement and wall cracking. The construction stability is extremely poor. Secondly, conventional clamps mostly use a ring structure with equal diameter, which can only achieve rigid clamping with a fixed force. They cannot adapt to the dynamic changes in the structural force during the jacking process. When the jacking force increases, the local stress concentration of the clamps can easily cause damage to the surface concrete of the original structural column and damage to the column itself, causing secondary damage to the existing building structure. Summary of the Invention

[0004] In view of this, in order to solve the problem that conventional clamps cause local stress concentration in the clamps after the lifting force increases, which can easily lead to damage to the surface concrete of the original structural columns and damage to the columns, causing secondary damage to the existing building structure, the present invention provides a support system and construction method for adding floors to existing building basements.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A replacement support system for adding floors to existing basements includes multiple sets of permanent piles pre-installed deep below the basement floor. Temporary support piles are connected to the top of the permanent piles via flanges. Each set of permanent piles consists of multiple piles surrounding the original structural columns.

[0007] A lifting seat is set on top of a temporary support pile. The lifting seat includes a hydraulic jack located at the top of the temporary support pile and a guide cylinder sleeved on the hydraulic jack. The output end of the hydraulic jack is fixedly connected to the top wall of the guide cylinder.

[0008] The clamp is fitted onto the existing structural column. The clamp is tapered, with a smaller top and a larger bottom. Multiple sliders are slidably installed inside the clamp, and the number of sliders corresponds to the number of exterior facades of the original structure. One side of the slider is connected to the guide tube.

[0009] When the hydraulic jack extends its output end out of the lifting guide cylinder and moves upward, it synchronously drives the slider to move upward. Since the clamping frame is conical, the slider moves closer to the original structural column as it rises, clamping the original structural column. As the lifting force increases, the clamping force also increases.

[0010] Furthermore, it also includes a load-bearing cap fitted onto the top of the temporary support piles, the load-bearing cap comprising:

[0011] Two semi-circular steel plates are clamped to the outer wall of the top of the temporary support pile. The two semi-circular steel plates are respectively machined with interlocking protrusions and grooves on the side of the two semi-circular steel plates that are close to each other. The protrusions and grooves are used to position the two semi-circular steel plates and prevent the two semi-circular steel plates from being misaligned.

[0012] Two top plates are fixed to the top of the semi-circular steel plate, respectively;

[0013] Two semi-cylinders are fixed to the top of the top plate respectively. As the two semi-cylinders approach each other, they form a complete cylindrical shape. The hydraulic jack is located between the two semi-cylinders, with its bottom abutting against the top of the two top plates.

[0014] Furthermore, the lifting platform also includes:

[0015] Two sets of screws I are fixed to the top of the two top plates respectively; multiple connecting ears are fixed to the outer wall of the top of the guide tube respectively, and the connecting ears are sleeved on the corresponding screws I;

[0016] Multiple nut rings are spirally sleeved on the corresponding screw I, with their tops abutting against the connecting lugs;

[0017] After the hydraulic jack is lifted into position, the nut ring is rotated so that the top of the nut ring abuts against the bottom of the connecting lug for rigid support.

[0018] Furthermore, a rotating seat I is fixedly provided at the top of the guide cylinder;

[0019] The outer wall of the clamp is provided with a rectangular hole corresponding to the slider, and the outer wall of the slider is fixed with a rotating seat Ⅲ located in the rectangular hole;

[0020] A connecting rod is hinged between rotating seat I and rotating seat III;

[0021] When rotating seat I drives rotating seat III to move upward via connecting rod, the connecting rod swings as rotating seat III tilts upward, thus preventing rotating seat I and rotating seat III from jamming.

[0022] Furthermore, one of the semicircular steel plates has a countersunk hole on one side, and a bolt is installed in the countersunk hole. The other semicircular steel plate has a threaded hole on one side, and one end of the bolt is threaded into the threaded hole to fix the two semicircular steel plates.

[0023] A sliding ring is provided inside the countersunk hole. Multiple wedges are integrally formed on the outer end face of the sliding ring. The wedges are evenly distributed along the circumference of the sliding ring. The side of each wedge facing the bolt screwing-in direction is a guide slope, and the side facing the bolt screwing-out direction is a limiting right angle surface.

[0024] The inner end face of the large end of the bolt is provided with a groove corresponding to each wedge. The side of each groove facing the bolt screwing in direction is a mating slope that matches the guide slope, and the side facing the bolt screwing out direction is a mating right angle that matches the limiting right angle.

[0025] A spring is provided between the large end of the bolt and the sliding ring. The spring is sleeved outside the bolt shank and located inside the countersunk hole. The two ends of the spring abut against the inner end face of the sliding ring and the inner sidewall of the countersunk hole, respectively, and always maintain the elastic force that pushes the sliding ring towards the large end of the bolt.

[0026] When the bolt is screwed into the threaded hole, the mating inclined surfaces of each slot slide into the guiding inclined surfaces of the corresponding wedges, driving the sliding ring to overcome the spring force and move towards the inside of the countersunk hole, avoiding the screwing path of the bolt.

[0027] When the bolt is screwed in, the sliding ring returns to its original position under the elastic force of the spring, and each wedge is engaged in the corresponding slot. The limiting right angle surface of each wedge and the mating right angle surface of the corresponding slot form an abutment limit along the bolt screwing out direction, preventing the bolt from screwing out in the opposite direction.

[0028] Furthermore, multiple limiting strips are integrally formed inside the countersunk hole, and the outer wall of the sliding ring is provided with positioning grooves that are adapted to the limiting strips to limit the circumferential movement of the sliding ring.

[0029] Furthermore, the outer wall of the sliding ring is integrally formed with an extension located inside the countersunk hole;

[0030] The outer side of the semi-circular steel plate has a socket that communicates with the countersunk hole;

[0031] When it is necessary to unscrew the bolt in the opposite direction, the wrench can be inserted into the countersunk hole through the mortise and tenon and moved inward against the extension to release the bolt from its restraint.

[0032] Furthermore, it also includes multiple cross braces located between two adjacent temporary support piles, the cross braces including:

[0033] A sleeve rod, one end of which is fixedly equipped with a semi-circular chuck I;

[0034] Screw II is threaded into the sleeve rod. A rotating seat II is fixedly provided at the outer end of screw II. A semi-circular pawl II is hinged to the other end of rotating seat II.

[0035] The rotating screw II moves within the sleeve to adjust the distance between the semicircular claw I and the semicircular claw II, so that the semicircular claw I and the semicircular claw II respectively abut against the outer wall of two adjacent temporary support piles.

[0036] Furthermore, a hexagonal block that mates with a wrench is fixedly fitted onto the outer wall of screw II;

[0037] The outer wall of screw II is threaded with a locking nut that abuts against one end of the sleeve rod, and screw II is locked by the locking nut and the sleeve rod.

[0038] A construction method, applied to the aforementioned underpinning support system for adding floors to existing building basements, includes the following steps:

[0039] S1. Drive permanent piles under the existing basement floor slab first, and then connect temporary support piles from the top of the permanent piles to temporarily support the weight of the building.

[0040] S2. Attach the two semi-circular steel plates to the top of the temporary support pile, and then use bolts to lock them in place from the outside, quickly assembling them into a temporary all-steel load-bearing platform.

[0041] S3. Corresponding to the height of the steel support platform below, assemble a set of clamps on the original structural columns of the building. The inner side of the clamps is equipped with sliders.

[0042] S4. Place the hydraulic jack on the semi-circular steel plate, and connect the rotating seat I and rotating seat III through the connecting rod. The hydraulic jack pressurizes and rises, and the upward thrust will drive the slider to tightly hug the column. The tighter it pushes, the more firmly it hugs.

[0043] S5. After the weight has stabilized, rotate the nut ring to move upward on screw I until the nut ring touches the bottom of the connecting lug, thus completing the force conversion.

[0044] S6. Before officially digging down, install the cross brace. The workers attach the crescent-shaped clips at both ends of the cross brace to two adjacent temporary support piles. They then use a wrench to adjust the length of the cross brace so that the semicircular clip I and semicircular clip II abut against the two adjacent temporary support piles respectively.

[0045] S7. After excavating to the preset depth, construct each floor slab and horizontal structure of the new basement from top to bottom, and finally pour the new structural columns.

[0046] S8. After the construction of the new structural columns is completed and they meet the load-bearing standards, the overall weight of the building will be transferred from the temporary support piles to the newly built structural columns.

[0047] S9. After the force conversion is completed, remove all the cross braces directly, then loosen the fixing bolts of the clamps and semi-circular steel plates. All temporary steel components will automatically loosen and be easily disassembled. Also, remove the temporary support piles next to the new structural columns in the newly built floor.

[0048] The beneficial effects of this invention are as follows:

[0049] 1. The replacement support system for the renovation of basement floors in existing buildings disclosed in this invention adopts a linkage structure of conical clamp frame and slider, combined with the vertical lifting drive of hydraulic jack and guide cylinder, to achieve synchronous linkage between lifting operation and column clamping operation. During the upward lifting of hydraulic jack, the slider can be driven to slide upward along the conical clamp frame and clamp the original structural column inward, so as to achieve synchronous increase of lifting force and clamping force, ensuring that the structural column is always stably clamped throughout the replacement process, avoiding column slippage and force displacement, and greatly improving construction safety and stability.

[0050] 2. The replacement support system for adding floors to existing building basements disclosed in this invention, through the hinged connection structure of rotating seat I, connecting rod, and rotating seat III, allows the connecting rod to adaptively swing and adjust its angle during the upward tilting of the slider. This effectively avoids the defects of motion jamming and force jamming in traditional rigid connection structures, ensuring smooth and continuous lifting and clamping actions, avoiding local stress concentration and structural deformation caused by structural jamming, and improving the motion reliability and force uniformity of the entire support system.

[0051] 3. The replacement support system for adding floors to existing building basements disclosed in this invention can achieve the force conversion from flexible hydraulic jacking to rigid steel structure support through the cooperation of screw I and nut ring after jacking into place, locking the support height and stress state, avoiding the disadvantages of traditional pure hydraulic support that is prone to pressure leakage and settlement during long-term construction, and is suitable for long-term construction conditions such as basement earthwork excavation and new structure pouring, greatly improving the long-term stability of the support system.

[0052] 4. The underpinning support system for adding floors to existing building basements disclosed in this invention has adjustable cross braces between adjacent temporary support piles. By matching the telescopic sleeve rods and screw rods II with different pile spacings, the dispersed independent piles can be connected into an overall frame structure, which effectively enhances the support system's resistance to lateral displacement and overturning, offsets the lateral earth pressure generated by earthwork excavation, avoids displacement and deformation of individual piles, and further improves the overall construction safety.

[0053] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0054] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0055] Figure 1 This is a three-dimensional structural schematic diagram of the underpinning support system for adding floors to existing building basements according to the present invention.

[0056] Figure 2 This is a partial structural schematic diagram of the underpinning support system for adding floors to existing building basements according to the present invention;

[0057] Figure 3 This is a schematic diagram of the interconnection of the semi-circular steel plates in this invention;

[0058] Figure 4 for Figure 3 Enlarged structural diagram of section A in the middle;

[0059] Figure 5 This is an exploded structural diagram of the lifting seat and the load-bearing platform in this invention;

[0060] Figure 6 This is a schematic diagram of the clamp frame structure in this invention;

[0061] Figure 7 This is a schematic diagram showing the connection between the rotating seat III and the connecting rod and rotating seat I in the clamp frame of the present invention;

[0062] Figure 8 This is a schematic diagram of the cross brace structure in this invention.

[0063] Attached reference numerals: 1. Permanent pile; 2. Temporary support pile; 3. Lifting seat; 31. Hydraulic jack; 32. Screw rod I; 33. Nut ring; 34. Guide cylinder; 35. Connecting lug; 36. Rotating seat I; 37. Connecting rod; 4. Cross brace; 41. Sleeve rod; 42. Semi-circular chuck I; 43. Screw rod II; 44. Rotating seat II; 45. Hexagonal block; 46. Locking nut; 47. Semi-circular chuck II; 5. 51. Clamping bracket; 52. Slider; 53. Rectangular hole; 54. Rotating seat III; 6. Load-bearing platform; 65. Semicircular steel plate; 66. Top plate; 67. Bolt; 68. Protrusion; 69. Groove; 60. Threaded hole; 61. Countersunk hole; 62. Insertion hole; 63. Limiting strip; 64. Sliding ring; 65. Positioning groove; 66. Wedge; 67. Spring; 68. Extension; 69. Semi-cylinder. Detailed Implementation

[0064] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0065] like Figure 1 The existing building's basement addition and renovation system shown here uses a specialized construction technique. The core structure consists of multiple sets of permanent piles 1, temporary support piles 2, a lifting seat 3, horizontal braces 4, clamps 5, and a load-bearing platform 6. The permanent piles 1 are pre-driven deep beneath the original basement floor level. The temporary support piles 2 connect to the top of the permanent piles 1. A flange is pre-embedded at the top of the permanent pile 1, and high-strength anchor bars are installed at the bottom of the flange, anchoring into the pile body. Similarly, a flange is pre-installed at the bottom of the temporary support piles 2, and high-strength bolts are used to lock them in place through the bolt holes of both flanges, completing the mechanical assembly between the permanent piles 1 and the temporary support piles 2. The entire structure is an underground pre-embedded foundation bearing structure. The multiple sets of permanent piles 1 are arranged according to the distribution points of the original structural columns, forming a ring-shaped bearing foundation that can evenly bear the vertical loads transmitted from the superstructure. Temporary support piles 2 extend upwards into the working space inside the basement. The tops of all temporary support piles 2 are uniformly leveled to ensure that the top surfaces are horizontally aligned, forming a complete vertical load-bearing pile structure. This enables the initial transfer of the load from the upper building and the positioning of temporary supports, providing an installation foundation for the upper support structure.

[0066] like Figure 2 As shown, each temporary support pile 2 is topped with a load-bearing platform 6. The load-bearing platform 6 is a steel composite bearing platform, serving as the installation base and load-bearing carrier for the lifting seat 3. It is mainly composed of two symmetrically arranged semi-circular steel plates 61, two top plates 62, and two semi-circular cylinders 615. The two semi-circular steel plates 61 are symmetrically interlocked and clamped onto the outer wall of the top of the temporary support pile 2. The inner arc surface of the semi-circular steel plates 61 fits snugly against the outer wall of the temporary support pile 2, ensuring a tight fit and uniform stress distribution after assembly. Figure 3 As shown, the two semi-circular steel plates 61 are integrally machined with protrusions 64 and grooves 65 on their interlocking sides. The protrusions 64 and grooves 65 are matched and interlocked. When the two semi-circular steel plates 61 are assembled together, the protrusions 64 are directly embedded in the corresponding grooves 65. The interlocking structure of the two semi-circular steel plates 61 is used to achieve the docking and positioning of the two semi-circular steel plates 61, restrict the vertical displacement between them, and ensure the stability and integrity of the overall assembly of the load-bearing platform 6.

[0067] like Figure 5As shown, a top plate 62 is fixedly installed on the top of each of the two semicircular steel plates 61. The two top plates 62 are symmetrically spliced ​​to form a complete horizontal bearing platform, providing a flat and load-bearing foundation for the upper lifting structure. A semicircular cylinder 615 is fixedly installed on the top surface of each top plate 62. The two semicircular cylinders 615 are synchronously combined with the interlocking splicing of the two semicircular steel plates 61 to form a complete circular cylindrical structure. The core component of the lifting seat 3 is nested inside this cylindrical structure to achieve limiting and positioning. To achieve the quick locking and self-locking anti-loosening function of the two semicircular steel plates 61, a stepped countersunk hole 67 is opened on the mating side of one of the semicircular steel plates 61, and a bolt 63 is inserted through the countersunk hole 67. A threaded hole 66 is opened on the corresponding side of the other semicircular steel plate 61. The end of the bolt 63 is threaded into the threaded hole 66, and the two semicircular steel plates 61 are fixedly assembled by threaded locking.

[0068] like Figure 4 As shown, a sliding ring 610 is slidably fitted inside the countersunk hole 67. The sliding ring 610 can slide smoothly along the axial direction of the countersunk hole 67. Multiple evenly distributed wedges 612 are integrally formed on the outer end of the sliding ring 610. The side of each wedge 612 facing the screw-in direction of the bolt 63 is a guiding inclined surface, and the side facing the screw-out direction of the bolt 63 is a limiting right-angle surface. The large end sidewall of the bolt 63 has grooves corresponding to the wedges 612. The side of each groove facing the screw-in direction of the bolt 63 is a mating inclined surface adapted to the guiding inclined surface, and the side facing the screw-out direction of the bolt 63 is a mating right-angle surface adapted to the limiting right-angle surface. A spring 613 is sleeved on the outside of the bolt 63. The spring 613 is arranged between the inner end face of the sliding ring 610 and the inner bottom surface of the countersunk hole 67, always maintaining an elastic pushing state. The inner wall of the countersunk hole 67 is integrally formed with multiple limiting strips 69. The outer wall of the sliding ring 610 is provided with a positioning groove 611 that matches the limiting strips 69. The limiting strips 69 and the positioning groove 611 engage and cooperate to realize the circumferential limitation of the sliding ring 610, while retaining only the axial sliding degree of freedom, ensuring that the wedge block 612 and the bolt 63 groove are always accurately aligned.

[0069] The outer end of the sliding ring 610 has an integrally formed extension 614. The outer surface of the semi-circular steel plate 61 has an insertion hole 68 that communicates with the countersunk hole 67. The insertion hole 68 serves as an unlocking operation channel, allowing external tools to be inserted for operation. During the forward tightening of the bolt 63, the inclined surface of the slot presses against the inclined surface of the wedge block 612, driving the sliding ring 610 to compress the spring 613 and retract inward, avoiding the screwing path of the bolt 63. When the bolt 63 is fully locked in place, the sliding ring 610 slides outward under the elastic restoring action of the spring 613, causing the wedge block 612 to engage with the slot of the bolt 63. At this time, the right-angled surface of the slot abuts against and limits the wedge block 612, preventing the bolt 63 from rotating in the opposite direction. This forms a mechanical self-locking structure, avoiding bolt loosening caused by construction vibration and load compression. When disassembly is required, insert the tool through the insertion hole 68 to press the extension part 614, causing the sliding ring 610 to retract inward, so that the wedge block 612 is disengaged from the slot limit, and the bolt 63 can be unscrewed to complete the disassembly and disassembly of the load-bearing platform 6.

[0070] The top of the load-bearing platform 6 is equipped with a lifting seat 3, which is the core component for realizing vertical lifting, load transfer, and structural rigidity locking. Figure 5 As shown, the main components include a hydraulic jack 31, a guide cylinder 34, two sets of screw rods I 32, multiple nut rings 33, multiple sets of connecting lugs 35, a connecting rod 37, a rotating seat I 36, and a rotating seat III 53. The hydraulic jack 31 is vertically nested inside the cylindrical structure formed by the combination of two semi-cylinders 615, and its bottom rests stably on the bearing platform formed by the splicing of two top plates 62, ensuring that the vertical force is vertically uniform. The two sets of screw rods I 32 are respectively vertically fixed to the top surfaces of the two top plates 62, providing vertical guidance and force support for the rigid locking of the upper structure.

[0071] The guide cylinder 34 is a vertical hollow cylindrical structure, which is entirely fitted over the hydraulic jack 31 and also fitted onto the two semi-cylinders 615 to form a guiding structure and further limit the position of the load-bearing platform 6. The fixed end of the hydraulic jack 31 is located on the top of the load-bearing platform 6, and the telescopic output end of the hydraulic jack 31 is fixedly connected to the center of the top wall of the guide cylinder 34. When the hydraulic jack 31 telescopically operates, it can synchronously drive the guide cylinder 34 to complete the vertical lifting and lowering movement. The top outer wall of the guide cylinder 34 is fixed with multiple sets of connecting ears 35, which are fitted one-to-one on the rod of the screw I 32 and can be adjusted vertically along the screw I 32. Each screw I 32 has a nut ring 33 spirally fitted on its rod, which is located below the corresponding connecting ear 35 and can be adjusted vertically by rotation. After the hydraulic jack 31 completes the lifting operation and the force stabilizes, the rotating nut ring 33 moves upward along the screw I 32, so that the top surface of the nut ring 33 tightly abuts against the bottom of the connecting lug 35. Through the rigid threaded engagement between the nut ring 33 and the screw I 32, the stress state of the guide cylinder 34 and the upper structure is changed from hydraulic flexible lifting to steel structure rigid support, locking the overall support height and avoiding the risk of support failure caused by long-term pressure relief and deformation of hydraulic equipment.

[0072] A rotating seat I36 is fixedly installed on the top of the guide cylinder 34. A clamping frame 5 is fitted on the outside of the original structural column. The clamping frame 5 is designed as a conical ring structure with a smaller top and a larger bottom, and it is also assembled in two halves. The conical slope provides a guide trajectory for the adaptive clamping motion of the slider 51. Figure 6 As shown, the annular sidewall of the clamping frame 5 has rectangular holes 52 matching the number of existing structural columns on the exterior facade. Inside the clamping frame 5, sliders 51 corresponding to the rectangular holes 52 are slidably fitted. The sliders 51 can slide vertically along the rectangular holes 52. The inner end face of the slider 51 is in contact with the existing structural column facade, and the outer side extends to the outside of the clamping frame 5 and is fixedly mounted on a rotating seat Ⅲ 53. For example... Figure 7 As shown, a connecting rod 37 is hinged between the rotating seat I 36 and the rotating seat III 53 at the corresponding positions. The two ends of the connecting rod 37 are hinged to swing freely through the pins, which can adaptively match the motion trajectory of the slider 51.

[0073] When the hydraulic jack 31 extends upwards from its output end, it simultaneously drives the guide cylinder 34 to move vertically upwards. The guide cylinder 34 pulls the connecting rod 37 through the rotating seat I 36 at the top. The connecting rod 37 pulls the rotating seat III 53 and the slider 51 to slide upwards along the rectangular hole 52. Relying on the conical structure of the clamping frame 5, the slider 51 gradually moves towards the center of the original structural column along the inner wall of the conical shape as it slides upwards. Multiple sliders 51 simultaneously and evenly squeeze and clamp the original structural column from all sides. The greater the lifting force of the hydraulic jack 31, the greater the upward displacement of the slider 51, and the clamping force on the structural column increases synchronously and linearly. This achieves the linkage and adaptive adjustment of the lifting force and clamping force, and stably completes the replacement and positioning of the upper structural load. At the same time, during the upward tilting of the slider 51, the connecting rod 37 can swing freely with the position change of the hinge seats at both ends, adaptively adjusting the tilt angle to avoid jamming of the hinge transmission structure and obstruction of movement, ensuring the smooth operation of the entire lifting and clamping structure.

[0074] The support system also includes a synchronous control system, which includes a controller, displacement sensors, and pressure sensors. The displacement sensors are installed at the telescopic ends of each hydraulic jack 31 to collect the lifting displacement of each jack in real time. The pressure sensors are installed at the oil circuit interfaces of each hydraulic jack 31 to collect the output pressure value of each jack in real time. The controller is electrically connected to the hydraulic control valves of each hydraulic jack 31, each displacement sensor, and each pressure sensor. The controller adopts a PID closed-loop synchronous control algorithm. Based on the displacement signals fed back by each displacement sensor and the pressure signals of each pressure sensor, the controller adjusts the opening of each hydraulic control valve to control multiple sets of hydraulic jacks 31 to lift or unload synchronously according to a preset lifting speed and a preset displacement. The lifting seat 3 and the load-bearing platform 6 are equipped with removable waterproof and dustproof covers. Each exposed threaded pair and hinge pin is equipped with a sealing ring or dustproof sleeve.

[0075] The entire support system is also equipped with multiple sets of horizontal braces 4, which are installed between every two adjacent temporary support piles 2. This connects the dispersed and independent temporary support piles 2 into a unified frame structure, effectively improving the support system's resistance to lateral displacement and overturning, offsetting the lateral earth pressure generated during basement excavation, and preventing single piles from shifting or deforming under stress. Figure 8 As shown, the cross brace 4 mainly consists of a sleeve rod 41, a screw rod II 43, a semi-circular pawl I 42, a semi-circular pawl II 47, a rotating seat II 44, a hexagonal block 45, and a locking nut 46. One end of the sleeve rod 41 is fixedly fitted with the semi-circular pawl I 42. A threaded inner hole is formed inside the sleeve rod 41, and the screw rod II 43 is threaded into the inside of the sleeve rod 41, allowing for adjustment of its telescopic length through rotation.

[0076] The outer end of screw II 43 is hinged to semi-circular claw II 47 via rotating seat II 44. Semi-circular claw I 42 and semi-circular claw II 47 are structurally matched and symmetrically arranged, and can be respectively clamped to the outer wall of two adjacent temporary support piles 2. A hexagonal block 45 is fixedly sleeved in the middle of the screw II 43. The hexagonal block 45 is compatible with conventional wrench tools, providing a force point for manual rotation and adjustment of screw II 43, facilitating quick adjustment of the overall length of the cross brace 4. A locking nut 46 is also threaded onto the screw II 43. After the length adjustment is completed, tighten the locking nut 46 to make it fit against the end of the sleeve rod 41. The relative position of screw II 43 and sleeve rod 41 is fixed by the threaded locking, locking the overall length of the cross brace 4, preventing length shrinkage or loosening during construction, and ensuring the stability of the overall frame structure.

[0077] The specific construction steps for the underpinning and support system used in the renovation of the basement of this existing building are as follows:

[0078] S1. Preliminary Pile Foundation Construction and Temporary Support Layout. The construction area of ​​the existing building's basement is cleared and the foundation leveled. The center points of the existing structural columns are accurately located. Multiple sets of permanent piles 1 are constructed in groups below the existing basement floor and around the corresponding structural columns, ensuring that each set of permanent piles 1 is evenly distributed around the corresponding existing structural columns. After the pile foundation construction is completed, standard curing is carried out until the pile foundation structure fully meets the strength requirements and has vertical bearing capacity. After curing, temporary support piles 2 are connected to the top of all permanent piles 1 via flanges. During construction, the pile height is uniformly controlled, and the tops of all temporary support piles 2 are leveled to ensure that the tops of all temporary support piles 2 are at the same horizontal level. The vertical pile structure composed of permanent piles 1 and temporary support piles 2 initially bears the self-weight load of the superstructure, completing the preliminary foundation support layout.

[0079] S2. Precise assembly and self-locking of the load-bearing platform. Select two sets of semi-circular steel plates 61 of corresponding specifications, align and fasten the two semi-circular steel plates 61, and clamp and fix them to the top outer wall of the temporary support pile 2. During the fastening process, ensure that the protrusions 64 and grooves 65 on the side are precisely engaged and aligned to achieve lateral positioning and prevent misalignment of the two semi-circular steel plates 61. After alignment, insert the bolt 63 through the countersunk hole 67 of one semi-circular steel plate 61 and align it with the threaded hole 66 of the other semi-circular steel plate 61 for tightening. During the tightening process, the end groove of the bolt 63 presses against the wedge 612 of the sliding ring 610, pushing the sliding ring 610 to compress the spring 613 and retract it inward to avoid the bolt 63's tightening path. Once the bolt 63 is fully tightened and the two semi-circular steel plates 61 are tightly fitted together, the tightening operation stops. The sliding ring 610 is reset under the elastic force of the spring 613, and the wedge 612 automatically engages in the slot of the bolt 63, forming a mechanical self-locking structure. This completes the overall assembly and fixation of the steel load-bearing platform 6, creating a flat and stable upper lifting platform.

[0080] S3. Assembly of the clamping frame and sliding clamping structure. Based on the installation elevation of the top bearing platform 6 of the temporary support pile 2, the conical clamping frame 5 is assembled on-site at the corresponding height position of the original structural column, ensuring that the clamping frame 5 is coaxially arranged and horizontally aligned with the original structural column. After assembly, matching sliders 51 are installed one by one in each rectangular hole 52 on the side wall of the clamping frame 5. During the assembly process, the sliding freedom of the sliders 51 is checked to ensure that the sliders 51 can slide smoothly vertically along the rectangular holes 52 without jamming or deviation. After the sliders 51 are assembled, connecting rods 37 are hinged between the rotating seat Ⅲ 53 on the outside of each slider 51 and the rotating seat Ⅰ 36 on the top of the guide cylinder 34, ensuring that the two ends of each connecting rod 37 are flexibly hinged and can swing freely, completing the overall assembly and docking of the clamping transmission structure.

[0081] S4. Lifting system assembly and adaptive clamping operation. On the bearing platform formed by splicing the two top plates 62 of the bearing platform 6, place the hydraulic jack 31 in the center, and nest the guide cylinder 34 around the hydraulic jack 31 to ensure that the hydraulic jack 31 is vertical and centered under force, while confirming that the output end of the hydraulic jack 31 is firmly fixed to the top wall of the guide cylinder 34. After the equipment inspection is completed and found to be correct, the synchronous control system is started. The controller synchronously controls each group of hydraulic jacks 31 to pressurize and lift according to the preset lifting speed curve. Each displacement sensor and pressure sensor feeds back the displacement and pressure signals of each jack to the controller in real time. The controller dynamically adjusts the opening of each hydraulic control valve through the PID closed-loop regulation algorithm to ensure that the displacement deviation of each group of jacks does not exceed ±2mm and the pressure deviation does not exceed ±5%, so as to realize the synchronous lifting and balanced force of multiple groups of jacks. The hydraulic jacks 31 pressurize slowly and uniformly, drive the output end to extend upward, and drive the guide cylinder 34 to lift vertically and smoothly. The guide cylinder 34 synchronously pulls each group of sliders 51 along the conical inner wall of the clamp frame 5 through the connecting rod 37 to slide upward. As the slider 51 rises, it continuously moves closer to and contracts towards the original structural column, evenly clamping the column from all sides. As the hydraulic jacking pressure steadily increases, the clamping force of the slider 51 on the structural column continues to increase, gradually and smoothly transferring the structural load of the superstructure to the entire support system. The structural condition is observed throughout the process to ensure no settlement, no displacement, and no abnormal structural noise.

[0082] S5. Rigid Force Conversion and Locking of the Support System. After the load on the superstructure has been completely transferred and the overall stress state has stabilized, stop the pressurization operation of the hydraulic jack 31 and maintain the current lifting height. Manually rotate the nut ring 33 on each screw rod I 32 one by one, so that the nut ring 33 moves slowly upward along the screw rod I 32 until the top surface of the nut ring 33 is completely and tightly abutted against the bottom of the corresponding connecting lug 35. Through the rigid threaded support structure of the nut ring 33 and the screw rod I 32, the flexible lifting force of the hydraulic jack 31 is replaced, completing the force mode conversion and completely locking the height and stress state of the superstructure support. This avoids the risk of pressure leakage and settlement that may occur when the hydraulic equipment is under pressure for a long time, and improves the long-term stability of the support system during construction.

[0083] S6. Overall Frame Cross Bracing Reinforcement. Before the formal excavation of the basement, complete the assembly and reinforcement of the cross braces 4 between all adjacent temporary support piles 2. Place the semi-circular claw I 42 at one end of a single cross brace 4 against the outer wall of one of the temporary support piles 2. Use a wrench to hold the hexagonal block 45 on the screw II 43 and rotate it, driving the screw II 43 to extend and retract inside the sleeve 41. Precisely adjust the overall effective length of the cross brace 4, ensuring that the semi-circular claw II 47 at the other end is tightly against the outer wall of the adjacent temporary support pile 2, guaranteeing a tight fit between the claws and the pile body and balanced force distribution. After length adjustment, tighten the locking nut 46 at the end of the screw II 43, ensuring that the locking nut 46 is tightly fitted against the end of the sleeve 41, locking the relative position of the screw II 43 and the sleeve 41, and fixing the overall length of the cross brace 4. Complete the assembly of all cross braces 4 according to the same process, and connect all the independent temporary support piles 2 into an overall frame structure to resist the lateral earth pressure generated by subsequent excavation construction and prevent the piles from tilting or shifting.

[0084] S7. Basement Excavation and New Structure Construction. After the entire support system is reinforced and passes inspection, the basement will be excavated layer by layer. The excavation process will follow the principles of layered, symmetrical, and uniform excavation, strictly controlling the depth of each excavation to avoid structural stress imbalance caused by excessive unloading of soil on one side. The settlement and displacement data of the support system and the superstructure will be monitored throughout the process. After the excavation reaches the preset design depth for the basement addition, the foundation will be leveled and compacted. Subsequently, the reinforcement binding, formwork support, and concrete pouring of the floor slabs and horizontal beams of the new basement will be carried out sequentially from top to bottom. After the horizontal structure construction is completed, the new structural columns will be poured. After all the new structural construction is completed, it will be fully cured according to the specifications until the concrete strength and overall structural load-bearing capacity fully meet the design load-bearing standards.

[0085] S8. Secondary Load Transfer and Load Reset. New structural columns are constructed below the existing structural columns in the newly excavated basement. After the new structural columns are poured and have reached their designed load-bearing capacity, a secondary load transfer operation is carried out. Hydraulic jacks 31 are slowly and gradually depressurized to reduce the lifting force on the temporary support system, allowing the upper building load to be smoothly and evenly transferred to the newly constructed basement structural columns. The building settlement and structural stress state are monitored in real time throughout the process to ensure a smooth and abrupt load transfer until the temporary support system is completely unloaded and the upper load is entirely borne by the new structure, completing the load reset.

[0086] S9. Temporary Component Removal and Site Cleanup. After the load transfer is completely stable, the temporary support components are removed. First, loosen the locking nuts 46 of all cross braces 4 one by one, rotate the hexagonal block 45 in the opposite direction to retract the screw II 43, release the clamping state of the semi-circular claws at both ends, and remove all cross brace 4 components. Then, unlock and disassemble the load-bearing platform 6. Insert the tool through the insertion hole 68 on the outside of the semi-circular steel plate 61, press down on the extension 614 of the sliding ring 610, drive the sliding ring 610 to retract, so that the wedge block 612 disengages from the slot limit of the bolt 63, release the self-locking state, and unscrew the bolt 63 in the opposite direction. Disassemble the two semi-circular steel plates 61, and remove all temporary steel components such as the top plate 62, the lifting seat 3, and the clamp frame 5 in sequence. The temporary support piles 2 next to the new structural columns in the newly built floor will be removed. If further excavation is required, temporary support piles 2 at a certain height can be reserved above the ground of the new floor to facilitate the subsequent installation and use of steel components such as the load-bearing platform 6, the lifting seat 3, and the clamp frame 5. After all temporary components are removed, the construction site will be cleaned and tidied up to complete the entire replacement construction process for the basement addition renovation of the existing building. The renovated basement structure is stable and fully meets the requirements of building use and safety specifications.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A support system for adding floors to existing building basements, characterized in that, The system includes multiple sets of permanent piles (1) driven deep below the basement floor and surrounding the original structural column, temporary support piles (2) connected to the top of the permanent piles (1), and a lifting seat (3) set on the top of the temporary support piles (2). The lifting seat (3) includes a hydraulic jack (31) located at the top of the temporary support piles (2) and a guide cylinder (34) sleeved on the hydraulic jack (31). The output end of the hydraulic jack (31) is fixedly connected to the top wall of the guide cylinder (34). A clamp frame (5) with a smaller top and a larger bottom is sleeved on the original structural column. Multiple sliders (51) are slidably installed inside the clamp frame (5) and rotatedly connected to the guide cylinder (34) on one side. When the output end of the hydraulic jack (31) extends out of the lifting guide cylinder (34) and moves upward, it synchronously drives the sliders (51) to move upward. Since the clamp frame (5) is conical, the sliders (51) move closer to the original structural column as they rise, clamping the original structural column. As the lifting force increases, the clamping force also increases.

2. The underpinning support system for adding floors to existing building basements as described in claim 1, characterized in that, It also includes a load-bearing platform (6) fitted on the top of the temporary support pile (2). The load-bearing platform (6) includes two semi-circular steel plates (61) clamped on the outer wall of the top of the temporary support pile (2). The two semi-circular steel plates (61) are respectively machined with interlocking protrusions (64) and grooves (65) on the side of the two semi-circular steel plates (61). A top plate (62) and a semi-circular cylinder (615) are fixedly installed on the top of the semi-circular steel plates (61). The hydraulic jack (31) is located in the cylindrical cavity formed by the docking of the two semi-circular cylinders (615), and its bottom abuts against the top of the two top plates (62).

3. The underpinning support system for adding floors to existing building basements as described in claim 2, characterized in that, The lifting seat (3) also includes screw I (32) fixed to the top of the two top plates (62) respectively, and connecting ears (35) fixed to the outer wall of the top of the guide cylinder (34) respectively. The connecting ears (35) are sleeved on the corresponding screw I (32). The screw I (32) is spirally sleeved with a nut ring (33) whose top abuts against the connecting ear (35). After the hydraulic jack (31) is lifted into place, the nut ring (33) is rotated so that the top of the nut ring (33) abuts against the bottom of the connecting ear (35) for rigid support.

4. The underpinning support system for adding floors to existing building basements as described in claim 3, characterized in that, The top of the guide cylinder (34) is fixedly provided with a rotating seat I (36); the outer wall of the clamping frame (5) is provided with a rectangular hole (52) corresponding to the slider (51), and the outer wall of the slider (51) is fixedly provided with a rotating seat III (53) located in the rectangular hole (52); a connecting rod (37) is hinged between the rotating seat I (36) and the rotating seat III (53).

5. The underpinning support system for adding floors to existing building basements as described in claim 4, characterized in that, One of the semicircular steel plates (61) has a countersunk hole (67) on one side, and a bolt (63) is installed in the countersunk hole (67). The other semicircular steel plate (61) has a threaded hole (66) on one side, and one end of the bolt (63) is threaded into the threaded hole (66) to fix the two semicircular steel plates (61). A sliding ring (610) is slidably installed in the countersunk hole (67). Multiple wedges (612) are integrally formed on the outer end face of the sliding ring (610). The wedges (612) are evenly distributed along the circumference of the sliding ring (610). The side of each wedge (612) facing the direction of screwing in the bolt (63) is a guide slope, and the side facing the direction of screwing out of the bolt (63) is a limiting right angle surface. The inner end face of the large end of the bolt (63) is provided with a slot corresponding to each wedge (612). The side of each slot facing the screw-in direction of the bolt (63) is a mating inclined surface adapted to the guide inclined surface, and the side facing the screw-out direction of the bolt (63) is a mating right angle surface adapted to the limiting right angle surface. A spring (613) is provided between the large end of the bolt (63) and the sliding ring (610). The spring (613) is sleeved on the outside of the rod of the bolt (63) and located in the countersunk hole (67). The two ends of the spring (613) abut against the inner end face of the sliding ring (610) and the inner side wall of the countersunk hole (67) respectively, and always maintain the elastic force that pushes the sliding ring (610) towards the large end of the bolt (63).

6. The underpinning support system for adding floors to existing building basements as described in claim 5, characterized in that, Multiple limiting strips (69) are integrally formed inside the countersunk hole (67), and the outer wall of the sliding ring (610) is provided with a positioning groove (611) that matches the limiting strips (69) to limit the circumferential movement of the sliding ring (610).

7. The underpinning support system for adding floors to existing building basements as described in claim 5, characterized in that, The outer wall of the sliding ring (610) is integrally formed with an extension (614) located in the countersunk hole (67); the outer side of the semi-circular steel plate (61) is provided with an insertion hole (68) that communicates with the countersunk hole (67).

8. The underpinning support system for adding floors to existing building basements as described in claim 5, characterized in that, It also includes multiple cross braces (4) located between two adjacent temporary support piles (2). The cross braces (4) include a threaded sleeve rod (41) and a screw rod II (43). One end of the sleeve rod (41) is fixedly provided with a semi-circular claw I (42). The outer end of the screw rod II (43) is fixedly provided with a rotating seat II (44). The other end of the rotating seat II (44) is hinged with a semi-circular claw II (47). The semi-circular claw I (42) and the semi-circular claw II (47) respectively abut against the outer wall of the two adjacent temporary support piles (2).

9. The underpinning support system for adding floors to existing building basements as described in claim 8, characterized in that, The outer wall of the screw II (43) is fixedly fitted with a hexagonal block (45) that mates with a wrench.

10. A construction method based on the underpinning support system for adding floors to existing building basements as described in claim 8, characterized in that, Includes the following steps: S1. Drive permanent piles (1) under the existing basement floor slab, and then connect temporary support piles (2) from the top of the permanent piles (1) to temporarily support the weight of the building. S2. Fasten the two semi-circular steel plates (61) to the top of the temporary support pile (2), and then use bolts (63) to lock them from the outside, quickly assembling them into a temporary load-bearing platform made of all steel. S3. Corresponding to the height of the steel support below, a set of clamps (5) is assembled on the original structural column of the building. The inner side of the clamps (5) is equipped with sliders (51). S4. Place a hydraulic jack (31) on a semi-circular steel plate (61), and connect rotating seat I (36) and rotating seat III (53) through a connecting rod (37). The hydraulic jack (31) is pressurized and raised. The upward thrust will drive the slider (51) to tightly hug the column. The tighter it is pushed, the more firmly it is hugged. S5. After the weight is stabilized, rotate the nut ring (33) and move it upward on the screw I (32) until the nut ring (33) touches the bottom of the connecting lug (35) to complete the force conversion. S6. Before officially digging down, install the cross brace (4). The workers attach the crescent-shaped buckles at both ends of the cross brace to two adjacent temporary support piles. Use a wrench to adjust the length of the cross brace (4) so ​​that the semicircular claw I (42) and semicircular claw II (47) abut against the two adjacent temporary support piles (2). S7. After excavating to the preset depth, construct each floor slab and horizontal structure of the new basement from top to bottom, and finally pour the new structural columns. S8. After the construction of the new structural column is completed and the stress standard is met, the overall weight of the building is transferred from the temporary support piles (2) back to the newly built structural column. S9. After the force conversion is completed, remove all the cross braces (4), then loosen the fixing bolts of the clamp frame (5) and the semi-circular steel plate (61). All temporary steel components will be automatically loosened and easily disassembled. The temporary support piles (2) on the side of the new structural column in the newly built floor will be removed.

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