A non-supporting structure system for dismantling load-bearing walls and its construction method

Abstract

The application discloses a support-free structure system for removing a load-bearing wall and a construction method thereof. The support-free structure system comprises side support columns and first patch plates arranged at two ends of the load-bearing wall to be removed. The side support columns comprise two steel columns arranged at intervals along the thickness direction of the load-bearing wall to be removed, and the first patch plates are horizontally connected between adjacent steel columns. The support-free structure system further comprises a top beam fixed horizontally at the top end of the side support columns. The top beam is provided with support beams arranged at intervals along the length direction of the top beam. The support beams are provided with connecting plates arranged between the removed load-bearing wall and the floor. The top surface of the connecting plate is fixed by structural adhesive bonding with the floor, and the bottom surface of the connecting plate is fixed by welding with the support beams. The technical scheme provided by the application has a reasonable structure, forms a permanent support system through the side support columns and the top beam, can completely bear the upper load before the load-bearing wall is removed, does not need to set up temporary supports, and simplifies the construction steps.

Description

Technical Field

[0001] This invention belongs to the field of building engineering technology and relates to a supportless structural system for demolishing load-bearing walls and its construction method. Background Technology

[0002] my country has a large number of existing masonry structures. Due to their age and historical constraints, these buildings not only suffer from structural degradation but also struggle to meet the functional upgrades required by economic and social development. Strengthening and renovating these buildings is a crucial solution, with the need for functional transformation of large spaces being particularly prominent, such as converting small office areas into open public spaces.

[0003] In such renovation projects, the demolition of load-bearing components is unavoidable, especially when it involves the demolition of an entire load-bearing wall or the modification of partial door and window openings. The original force transmission path will be significantly altered, necessitating structural reinforcement measures to ensure safety. This places higher demands on construction technology. To ensure structural safety, existing technologies typically require first erecting a scaffolding support system, then demolishing the original wall, then setting up concrete transfer beam and column formwork and pouring concrete transfer beams and columns, and finally dismantling the relevant formwork and scaffolding support system. This approach is complex and involves high investment costs.

[0004] Therefore, there is an urgent need to design a support-free structural system and its construction method for demolishing load-bearing walls, in order to solve the technical problems existing in the current technology. Summary of the Invention

[0005] The purpose of this invention is to at least partially solve some of the technical problems existing in the prior art, and to provide a supportless structural system and its construction method for demolishing load-bearing walls. Its structure is rational, forming a permanent support system through side support columns and top beams, which can fully bear the upper load before demolishing the load-bearing wall, eliminating the need for temporary supports, simplifying construction steps, and reducing the time and labor costs of support installation and dismantling. This system allows for continuous operation, shortening the total construction period by approximately 30%-50%, while reducing obstacles on the construction site, facilitating machinery and personnel operation, and improving overall efficiency.

[0006] To address the aforementioned technical problems, this invention provides a supportless structural system for demolishing load-bearing walls, comprising side support columns and first connecting plates, which are disposed at both ends of the load-bearing wall to be demolished. Each side support column comprises two steel columns spaced apart along the thickness direction of the load-bearing wall to be demolished, with the first connecting plate horizontally connecting adjacent steel columns. It also includes a top beam horizontally fixed to the top of the side support columns. A support beam is provided on the upper part of the top beam, spaced apart along its length. A connecting plate is provided on the upper part of the support beam, positioned between the load-bearing wall to be demolished and the floor slab. The top surface of the connecting plate is bonded to the floor slab with structural adhesive, and its bottom surface is welded to the support beam. Strain gauges are installed at key stress-bearing locations of the steel columns, support beams, and top beam, and each strain gauge is connected to a monitoring system for dynamic stress monitoring during construction.

[0007] In some embodiments, the steel column is an I-beam, which is vertically embedded in the existing wall structure on both sides of the load-bearing wall to be demolished, and at least one strain gauge is arranged in the middle of the web and the end of the flange of each steel column.

[0008] In some embodiments, the height of the steel column is the same as the height of the load-bearing wall to be demolished, and its bottom column base is integrated with the foundation.

[0009] In some embodiments, the top beam is an I-beam, the same number as the steel columns, which are welded perpendicularly to form two steel frames, and strain gauges are arranged at the lower flange of each top beam at mid-span and at the node area where it connects to the steel column.

[0010] In some embodiments, there are multiple support beams that are vertically welded to the top beam. The support beams are evenly spaced along the length of the top beam, and strain gauges are arranged on the lower flange at mid-span and the areas with large shear forces at both ends of each support beam.

[0011] In some embodiments, the connecting plate is a steel plate with a thickness of 5-10 mm.

[0012] In some embodiments, the supportless structural system further includes multiple second gusset plates welded to the underside of the top beam.

[0013] Furthermore, the present invention also provides a method for demolishing a load-bearing wall, which uses the above-described supportless structural system for demolishing load-bearing walls, including: S1, side support columns are installed at both ends of the load-bearing wall to be demolished, and first gusset plates are installed on both sides of the side support columns; strain gauges are installed at predetermined positions on the steel columns and connected to the monitoring system; S2, A top beam is installed on the top of the load-bearing wall to be demolished, and several support beams are installed on the upper part of the top beam; strain gauges are installed at predetermined positions on the top beam and support beams and connected to the monitoring system; the monitoring system is started to obtain initial readings and is zeroed; S3, A connecting plate is installed above the supporting beam; S4. Under dynamic monitoring, the load-bearing wall is demolished, and the demolition sequence or speed is adjusted according to the stress data fed back by the monitoring system. Several second gusset plates are welded below the top beam.

[0014] In some embodiments, the second gusset plate is welded to the lower flange of the top beam on three sides.

[0015] In some embodiments, the side support columns, top beams, and connecting plates are fitted to the existing structure. If there are gaps between the newly added components and the existing structure, pressure grouting is used to fill them. The monitoring system includes a data acquisition unit and a display and alarm unit. When the strain value at any monitoring point exceeds a preset safety threshold, an audible and visual alarm is triggered.

[0016] Beneficial effects of this invention: This invention provides a support-free structural system for demolishing load-bearing walls and its construction method. The system has a reasonable structure and the following beneficial effects: a. Enables support-free construction, significantly improving construction efficiency: A permanent support system formed by side support columns and top beams allows the system to fully bear the upper load before the removal of load-bearing walls, eliminating the need for temporary supports. This simplifies construction steps and reduces the time and labor costs associated with support installation and removal. The system allows for continuous operation, shortening the overall construction period by approximately 30%-50%, while also reducing obstacles on the construction site, facilitating machinery and personnel operation, and improving overall efficiency.

[0017] b. Enhanced Structural Stability and Safety: The side support columns employ a double steel column design and are embedded in the existing wall, connecting with the first gusset plate to form a stable frame. The top beam and support beam are welded to form a rigid grid, effectively dispersing the upper load and avoiding stress concentration. During demolition, this system maintains overall structural stability, preventing floor slab subsidence or wall cracking, reducing the risk of safety accidents, and is particularly suitable for high-rise or heavily loaded buildings. Specifically, by arranging strain gauges in key stress-bearing components such as steel columns, top beams, and support beams and connecting them to a monitoring system, dynamic and real-time monitoring of the structural system's stress state is achieved. Construction personnel can intuitively grasp the actual stress changes during load transfer, providing accurate data support for construction decisions, upgrading traditional passive protection to proactive early warning and process control, and greatly improving the safety level of the construction process.

[0018] c. Providing reliable connections to ensure effective load transfer: The connecting plates are bonded to the floor slab with structural adhesive and welded to the supporting beams, forming multiple connection safeguards. The structural adhesive fills the gaps between the floor slab and the connecting plates, achieving uniform load transfer; the welded connection provides a high-strength bond, preventing relative displacement. This connection method adapts to uneven floor surfaces, improving force transmission efficiency and structural integrity.

[0019] d. High adaptability, suitable for various building conditions: Standard I-beams are used for steel columns and top beams, which can be flexibly selected according to the height, thickness, and load requirements of the wall to be demolished; Support beams are spaced along the length of the top beam, and the spacing is adjustable to adapt to different spans and floor structures. Pressure grouting can fill gaps between new components and existing structures, enhancing the system's adaptability to irregular buildings.

[0020] e. High construction precision and controllable quality: The method clearly defines welding and bonding processes, such as the three-sided welding of the second gusset plate to the lower flange of the top beam, ensuring connection strength; step S4 involves welding the second gusset plate after removal to further solidify the system. Pressure grouting fills the gaps, ensuring a tight fit between the new components and the original structure, improving construction quality and consistency, and reducing human error. Combined with dynamic monitoring data, the construction process can be finely adjusted based on real-time stress feedback, such as optimizing the removal sequence or speed, upgrading construction quality from simple process control to closed-loop control based on real-time mechanical performance feedback, ensuring the reliability of the final structural state.

[0021] f. Good economic efficiency and reduced overall cost: It eliminates the material, transportation, and labor costs of temporary supports, and reduces equipment rental expenses; the permanent support system, as part of the structure, does not require subsequent dismantling, reducing the total project cost. The shortened construction period also reduces management costs and indirect expenses, improving the project's economic efficiency.

[0022] g. Enhanced long-term durability and environmental friendliness: The support system integrates seamlessly with the existing structure through embedding and bonding, avoiding localized damage that may be caused by traditional temporary supports; steel components can undergo anti-corrosion treatment to ensure long-term corrosion resistance. Simultaneously, reducing the use of temporary supports lowers material waste, aligns with green construction principles, and minimizes vibration and noise during construction, resulting in less impact on the surrounding environment.

[0023] h. Simple operation and lower technical threshold: The construction method and steps are clear, requiring no complicated equipment or highly skilled workers. The installation of side support columns and top beams can be completed through conventional welding, and ordinary structural adhesive is used for bonding the connecting plates. This makes it easy to promote and apply to various building renovation projects, improving the feasibility and reliability of construction.

[0024] i. Achieving digital management and traceability of the construction process: By integrating a strain monitoring system, structural response data throughout the entire load-bearing wall demolition process is fully recorded, forming a valuable digital construction archive. This not only facilitates real-time monitoring but also provides data references for post-project analysis, project acceptance, and similar projects, promoting the development of demolition construction towards intelligence and informatization. Attached Figure Description

[0025] The advantages of the present invention will become clearer and more readily understood through the following detailed description in conjunction with the accompanying drawings, which are merely illustrative and do not limit the invention, wherein: Figure 1 This is a schematic diagram of a support-free structural system for demolishing load-bearing walls as described in this invention; Figure 2 yes Figure 1 A magnified view of a portion within the rectangular frame; Figure 3 yes Figure 1 A diagram corresponding to AA; Figure 4 yes Figure 1 A diagram corresponding to BB; Figure 5 This is a flowchart of the construction method for the unsupported structural system for demolishing load-bearing walls as described in this invention.

[0026] In the attached diagram, the components represented by each number are as follows: 10. Side support column; 11. Steel column; 20. First gusset plate; 30. Top beam; 40. Support beam; 50. Connecting plate; 60. Floor slab; 70. Second gusset plate. Detailed Implementation

[0027] Figures 1 to 5 This is a schematic diagram of a support-free structural system for demolishing load-bearing walls and its construction method as described in this application. The invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0028] The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the invention, and are illustrative and exemplary, and should not be construed as limiting the implementation or scope of the invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0029] The accompanying drawings in this specification are schematic diagrams to aid in illustrating the concept of the invention, and schematically show the shapes of the various parts and their interrelationships. Please note that, in order to clearly demonstrate the structure of the components in the embodiments of the invention, the drawings are not drawn to the same scale. The same reference numerals are used to indicate the same parts.

[0030] A schematic diagram of a support-free structural system for demolishing load-bearing walls as described in this invention is shown below. Figure 1 As shown. The unsupported structural system for demolishing load-bearing walls includes side support columns 10 and first connecting plates 20, which are installed at both ends of the load-bearing wall to be demolished; the side support columns 10 include two steel columns 11, as shown. Figure 2 As shown, the steel columns 11 are spaced apart along the thickness direction of the load-bearing wall to be demolished, and the first connecting plate 20 is horizontally connected between adjacent steel columns 11. Multiple first connecting plates 20 are arranged vertically to form a stable truss structure, thereby connecting two independent steel columns 11 into a single, collaboratively load-bearing side-support column unit, greatly enhancing its lateral stability under load and effectively preventing the instability of a single steel column. Resistance strain gauges are pre-installed at key locations such as the middle of the web and the ends of the flanges of each steel column 11 to monitor the strain state of the steel column under compressive and bending loads during construction.

[0031] Furthermore, the unsupported structural system also includes a top beam 30, such as... Figure 3 As shown, it is horizontally fixed to the top of the side support column 10; a support beam 40 is provided on the upper part of the top beam 30, and the support beams 40 are spaced apart along the length of the top beam 30; a connecting plate 50 is provided on the upper part of the support beam 40, which is located between the demolished load-bearing wall and the floor slab 60; the top surface of the connecting plate 50 is bonded to the floor slab 60 with structural adhesive, and its bottom surface is welded to the support beam 40. Strain gauges are also arranged at the lower flange of the top beam 30 at mid-span and at the node area where it connects to the steel column 11 to monitor the bending and shear effects of the top beam when bearing the upper load. Strain gauges are also installed at the lower flange of each support beam 40 at mid-span and at both ends of the support beam where the shear force is large, to monitor the distribution of the floor load transmitted to the support beam through the connecting plate. The top surface of the connecting plate 50 is sandblasted to increase its roughness before bonding and then coated with high-strength epoxy resin structural adhesive. This adhesive not only has high bonding strength but also possesses a certain elastic modulus, ensuring effective load transfer while accommodating minor deformations. The bottom surface of the connecting plate 50 is welded to the supporting beam 40 using continuous fillet welds to ensure connection rigidity and strength. To optimize stress distribution, the spacing of the supporting beams 40 is calculated and typically controlled between 600mm and 1000mm to ensure effective support for the floor slab 60 and avoid excessive local deflection.

[0032] In this invention, the steel column 11 is an I-beam, such as... Figure 4 As shown, it is vertically embedded in the existing wall structure on both sides of the load-bearing wall to be demolished. During installation, a precise groove is first chiseled in the existing wall, and after the steel column 11 is in place, it is filled with high-strength non-shrink grout, so that the steel column 11 and the original wall form an integral whole and share the load.

[0033] Furthermore, the height of the steel column 11 is the same as the height of the load-bearing wall to be demolished, and its base is integrated with the foundation. The base is reliably connected to the foundation by pre-embedded anchor bolts or chemical anchoring, and the load is directly transferred to the foundation, with a clear and reliable force transmission path.

[0034] The top beam 30 is an I-beam, and the number of top beams 30 and steel columns 11 are the same. They are welded perpendicularly to form two steel frames. The flanges of the top beam 30 and the steel columns 11 are welded with bevel penetration welds to ensure rigid joint connection and form a sturdy portal frame as the main load-bearing skeleton.

[0035] There are multiple support beams 40, which are vertically welded to the top beam 30, and the support beams 40 are evenly spaced along the length of the top beam 30. The spacing of the support beams 40 can be precisely adjusted according to the thickness of the upper floor slab 60 and the load, reflecting the system's strong adaptability and suitability for various building conditions. For cases with large spans, the support beams 40 can be appropriately densified.

[0036] The connecting plate 50 is made of steel with a thickness of 5-10mm. This thickness range has been verified through mechanical calculations and engineering practice, ensuring both rigidity and strength while also being economical. The dimensions of the connecting plate 50 should extend its edge beyond the outermost supporting beam 40 by a certain distance to ensure that the support range covers the entire area to be demolished.

[0037] The unsupported structural system also includes multiple second gusset plates 70, which are welded to the lower part of the top beam 30. The second gusset plates 70 are welded after the load-bearing wall is removed. Their main function is to replace the removed wall and provide lateral support for the lower flange of the top beam 30, preventing the beam from becoming unstable out-of-plane under compression, and further enhancing the structural stability and safety.

[0038] All strain gauge signal leads converge and connect to a field monitoring system. This system includes a data acquisition module, a data processing and display unit, and an early warning module. The data acquisition module automatically collects strain data from each measuring point at a set frequency (e.g., once per second), processes the data, and displays it in real-time on the display unit in the form of numbers and trend graphs. The early warning module presets stress safety thresholds at various levels. When the measured stress value at any measuring point exceeds the preset threshold, the system immediately triggers an audible and visual alarm to alert on-site personnel to take intervention measures.

[0039] Furthermore, this invention also provides a method for demolishing load-bearing walls, which utilizes the aforementioned supportless structural system for demolishing load-bearing walls, as illustrated in the flowchart below. Figure 5 As shown, it includes: S1, side support columns 10 are set at both ends of the load-bearing wall to be demolished, and first gusset plates 20 are set on both sides of the side support columns 10. S1a, Strain gauges are installed at the predetermined stress points of the steel column 11, and signal wires are temporarily fixed and connected to the data acquisition channel of the monitoring system.

[0040] Before construction, this step involves calculating and confirming the cross-sectional dimensions and embedment depth of the side support column 10 to ensure it can withstand the entire load during dismantling. During installation, a theodolite or laser plumb line must be used for bidirectional verticality correction to ensure installation accuracy.

[0041] S2, a top beam 30 is installed on the top of the load-bearing wall to be demolished, and several supporting beams 40 are installed on the top beam 30. S2a, strain gauges are installed at the predetermined stress-bearing locations of the top beam 30 and the support beam 40, and connected to the monitoring system.

[0042] S2b: Start the monitoring system, collect initial readings from all strain measurement points and zero them, and record the initial state of the support system before it is subjected to the removal load.

[0043] After the top beam 30 is installed in place, it is tightened and temporarily fixed to the steel column 11, followed by welding. After welding, a pre-load test can be performed on the support system. The upper load is simulated using equipment such as jacks to verify the reliability of the system before proceeding to the next step. This greatly improves construction accuracy and safety. At this time, the monitoring system can simultaneously record the strain response during the pre-loading process and verify it against theoretical calculations.

[0044] S3, A connecting plate 50 is provided above the support beam 40; This step is crucial for ensuring effective load transfer. Before applying the structural adhesive, the bottom surface of the floor slab 60 must be cleaned and sanded. After the connecting plate 50 is in place, its own weight or the application of temporary counterweights should be used to ensure the structural adhesive layer is compacted, uniform, and free of voids. Disturbance should be avoided during the curing process of the structural adhesive.

[0045] S4. Under the real-time data monitoring of the monitoring system, the load-bearing wall is demolished. During the demolition process, the stress change trend of each measuring point displayed by the monitoring system is monitored throughout. The demolition sequence (e.g., from top to bottom, segmented demolition) and demolition speed can be dynamically adjusted according to the real-time feedback stress data to ensure that the stress of key components is always within the safe threshold. After demolishing the load-bearing wall, several second gusset plates 70 are welded below the top beam 30.

[0046] Once the structural adhesive has fully cured and reached its designed strength, the load-bearing wall can be safely removed. After the wall is removed, the second 70mm gusset plate is immediately welded at the designed spacing. The entire removal process requires no temporary support, achieving truly support-free construction and significantly improving construction efficiency.

[0047] Furthermore, the second gusset plate 70 is welded to the lower flange of the top beam 30 on three sides. The three-sided welding (both sides and the end) provides excellent shear and tensile strength, ensuring a reliable connection between the second gusset plate 70 and the top beam 30.

[0048] In this invention, the side support column 10, top beam 30, and connecting plate 50 are fitted into the existing structure. If gaps exist between the newly added components and the existing structure, they are filled using pressure grouting. The pressure grouting uses a specialized grouting material with good fluidity, micro-expansion, and early-strength high properties. Grouting begins at the lowest point and is sealed after a homogeneous grout flows out of the vent pipe at the highest point, ensuring all gaps are completely filled. This measure effectively addresses construction gaps, ensures the coordinated operation of the new and old structures, and improves the overall integrity and long-term durability of the system.

[0049] After construction is completed, the complete strain-time data recorded by the monitoring system can be exported and archived as important technical evidence of the safe and controllable construction and as reference material for similar projects in the future.

[0050] This invention is not limited to the above-described embodiments. Anyone can derive other products in various forms under the guidance of this invention. However, regardless of any changes in shape or structure, any technical solution that is the same as or similar to this application falls within the protection scope of this invention.

Claims

1. A supportless structural system for demolishing load-bearing walls, characterized in that, The system includes side support columns (10) and first connecting plates (20), which are installed at both ends of the load-bearing wall to be demolished. The side support columns (10) include two steel columns (11), which are spaced apart along the thickness direction of the load-bearing wall to be demolished. The first connecting plates (20) are horizontally connected between adjacent steel columns (11). The system also includes a top beam (30), which is horizontally fixed to the top of the side support columns (10). A support beam (40) is provided on the upper part of the top beam (30), and the support beam (40) is along the top beam. (30) is spaced along its length; a connecting plate (50) is provided on the upper part of the supporting beam (40), which is located between the demolished load-bearing wall and the floor slab (60); the top surface of the connecting plate (50) is bonded to the floor slab (60) with structural adhesive, and its bottom surface is welded to the supporting beam (40); strain gauges are provided on the key stress-bearing parts of the steel column (11), the supporting beam (40) and the top beam (30), and each strain gauge is connected to a monitoring system for dynamic stress monitoring during construction. The steel column (11) is an I-beam, which is vertically embedded in the existing wall structure on both sides of the load-bearing wall to be demolished, and at least one strain gauge is arranged in the middle of the web and the end of the flange of each steel column (11); the height of the steel column (11) is the same as the height of the load-bearing wall to be demolished, and the column foot at the bottom is connected to the foundation as a whole; the top beam (30) is an I-beam, which is the same number as the steel column (11), and the two are welded vertically to form two steel frames, and the strain gauge is arranged in the lower flange of the middle span and the node area connected to the steel column (11) of each top beam (30); there are multiple support beams (40), which are vertically welded to the top beam (30), and the support beams (40) are evenly spaced along the length direction of the top beam (30), and the strain gauge is arranged in the lower flange of the middle span and the area with large shear force at both ends of each support beam (40).

2. The supportless structural system for demolishing load-bearing walls according to claim 1, characterized in that, The connecting plate (50) is a steel plate with a thickness of 5-10mm.

3. The supportless structural system for demolishing load-bearing walls according to claim 1, characterized in that, It also includes a second gusset plate (70), which is multiple and welded to the underside of the top beam (30).

4. A method for demolishing a load-bearing wall, characterized in that, Using the unsupported structural system for demolishing load-bearing walls as described in any one of claims 1 to 3, comprising: S1, side support columns (10) are set at both ends of the load-bearing wall to be demolished, and first gusset plates (20) are set on both sides of the side support columns (10); strain gauges are installed at predetermined positions on the steel columns (11) and connected to the monitoring system; S2, a top beam (30) is set on the top of the load-bearing wall to be demolished, and several support beams (40) are set on the upper part of the top beam (30); strain gauges are installed at predetermined positions on the top beam (30) and support beams (40) and connected to the monitoring system; the monitoring system is started, the initial readings are obtained and zeroed; S3, A connecting plate (50) is provided above the support beam (40); S4, under dynamic monitoring, the load-bearing wall is demolished, and the demolition sequence or speed is adjusted according to the stress data fed back by the monitoring system. Several second gusset plates (70) are welded below the top beam (30).

5. The method for demolishing a load-bearing wall according to claim 4, characterized in that, The second gusset plate (70) is welded to the lower flange of the top beam (30) on three sides.

6. The method for demolishing a load-bearing wall according to claim 5, characterized in that, The side support column (10), top beam (30) and connecting plate (50) are fitted to the existing structure. If there is a gap between the new component and the existing structure, pressure grouting is used to fill it. The monitoring system includes a data acquisition unit and a display alarm unit. When the strain value of any monitoring point exceeds the preset safety threshold, an audible and visual alarm is triggered.

Images