Method for repairing wooden floor after fire

Abstract

The invention discloses a method for repairing a wooden floor after a fire, and relates to the technical field of wooden component fire repair, the method comprises the following steps: peeling off a carbonized layer: peeling off the carbonized layer on a damaged component to form a first bonding surface on the damaged side of the residual damaged component; the side, used for making contact with the damaged component, of the filling component is a second bonding face, and the first bonding face and the second bonding face are bonded and fixed through an adhesive. According to the repairing method, the bearing capacity of the damaged component after the fire disaster can be recovered, the cost is lower, and the safety is higher.

Description

Technical Field

[0001] The invention relates to the technical field of fire repair of wooden components, in particular to a method for repairing a wooden floor after a fire. Background Art

[0002] Cross Laminated Timber (CLT) has the advantages of excellent mechanical properties, good dimensional stability, high degree of prefabrication and good fire resistance. It is often used as floor or wall panels in multi-story modern wooden structures. As a heavy wood structure component, CLT will form carbonized substances on the outer surface during a fire to slow down further damage to the cross section, thus having better fire resistance than conventional steel structures. However, after a fire, the carbonized substances on the CLT components will cause the bearing capacity of the components to decrease. If the entire component is replaced, it will not only be costly, but also easily affect the entire building structure due to the removal of necessary supporting structures, causing safety problems during construction. At present, there is also a lack of methods for repairing wooden floors after fire. Therefore, there is an urgent need for a method for repairing wooden floors after fire that can restore the bearing capacity of damaged components after a fire, has lower costs and is safer. Summary of the invention

[0003] The purpose of the present invention is to provide a method for repairing wooden floors after fire, so as to solve the problems existing in the above-mentioned prior art, and to restore the bearing capacity of damaged components after fire, with lower cost and greater safety.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a method for repairing a wooden floor after a fire, comprising the following steps:

[0006] Peeling off the carbonized layer: peeling off the carbonized layer on the damaged component to form a first bonding surface on the damaged side of the remaining damaged component;

[0007] Bonding the filling component: The side of the filling component used to contact the damaged component is the second bonding surface, and the first bonding surface and the second bonding surface are bonded and fixed by an adhesive.

[0008] Preferably, before the step of stripping the carbonized layer, the method further includes determining the stripping thickness: measuring and calculating the thickness of the carbonized material at multiple positions on the damaged side of the damaged component, drawing a carbonized surface on the three-dimensional model of the damaged component according to the thickness of the carbonized material at each position, the carbonized surface being the interface between the carbonized material and the non-damaged part of the damaged component, and determining the thickness of the damaged component to be stripped according to the depth of the carbonized surface in the damaged component.

[0009] Preferably, the step of bonding the filling member further comprises: after the first adhesive surface and the second adhesive surface are bonded and fixed, applying pressure to the filling member so that the filling member is pressed tightly against the adhesive.

[0010] Preferably, in the step of bonding the filling member: pressure is applied to the filling member by means of self-tapping screws, a plurality of the self-tapping screws are driven into the filling member from the side of the filling member away from the damaged member, and a portion of each of the self-tapping screws is driven into the damaged member.

[0011] Preferably, when driving the self-tapping screws, the self-tapping screws in the middle of the filling member are driven in first, and then the self-tapping screws at the edge of the filling member are driven in.

[0012] Preferably, after the step of bonding and filling the component is completed, it also includes: fireproofing treatment: removing each of the self-tapping screws, and performing fireproofing sealing on the nail holes formed after removing the self-tapping screws.

[0013] Preferably, the step of determining the peeling thickness further comprises: using a drill rod capable of drilling into a resistance detector to drill into and penetrate the damaged component from multiple locations on the non-damaged side of the damaged component, and estimating the thickness of the carbonized material at the multiple locations based on changes in resistance.

[0014] Preferably, in the step of stripping the carbonized layer, the damaged side of the damaged component is planed multiple times to strip the carbonized layer, and the thickness of each planing is 5 mm to 8 mm.

[0015] Preferably, the adhesive is a gap-filling phenol resorcinol formaldehyde adhesive.

[0016] Preferably, the strength grade of the filling component is not less than the strength grade of the damaged component.

[0017] Compared with the prior art, the present invention has achieved the following technical effects:

[0018] The method for repairing a wooden floor after a fire provided by the present invention effectively restores the bearing capacity of the components after the fire by peeling off the carbonized layer on the damaged components after the fire and pasting new components. At the same time, since the damaged components do not need to be removed as a whole, the amount of materials used is effectively reduced, and the cost is lower. Moreover, since some damaged components are retained on the building structure after the carbonized layer is removed, the original support is continued, thereby avoiding the impact on the entire building structure when the components are removed as a whole, and the safety is stronger. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of determining the peeling thickness in the method for repairing a wooden floor after a fire provided by the present invention;

[0021] Figure 2 A schematic diagram of the structure of the damaged component after the carbonized layer is removed in the method for repairing a wooden floor after a fire provided by the present invention;

[0022] Figure 3 A schematic diagram of the method for repairing a wooden floor after a fire provided by the present invention when a filling component is pasted to a damaged component;

[0023] Figure 4 A schematic diagram of applying pressure to a filling member in the method for repairing a wooden floor after a fire provided by the present invention;

[0024] Figure 5 A schematic diagram of the structure of the components after the repair is completed in the method for repairing a wooden floor after a fire provided by the present invention;

[0025] In the figure: 1-damaged component, 11-first bonding surface, 2-carbonized layer, 3-filling component, 31-second bonding surface, 4-glue layer, 5-drillable resistance detector, 6-self-tapping screw. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The purpose of the present invention is to provide a method for repairing wooden floors after fire, so as to solve the problems existing in the above-mentioned prior art, and to restore the bearing capacity of damaged components after fire, with lower cost and greater safety.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Embodiment 1

[0030] This embodiment provides a method for repairing a wooden floor after a fire. Figure 1-5 As shown, the following steps are included:

[0031] Peeling off the carbonized layer 2: Figure 2 As shown, the carbonized layer 2 on the damaged component 1 is peeled off to form a first bonding surface 11 on the damaged side of the remaining damaged component 1;

[0032] Bonding filling component 3: Figure 3 As shown, the side of the filling component 3 that contacts the damaged component 1 is the second bonding surface 31 , and the first bonding surface 11 and the second bonding surface 31 are bonded and fixed by an adhesive.

[0033] The repair method of the wooden floor after fire provided in this embodiment is mostly used for wooden floor structure, and can also be used for wooden wallboard or other wooden components. The repair method effectively restores the bearing capacity of the component after fire by peeling off the carbonized layer 2 on the damaged component 1 after fire and pasting a new component. At the same time, since there is no need to remove the damaged component 1 as a whole, the amount of material is effectively reduced, and the cost is lower. Moreover, since after removing the carbonized layer 2, part of the damaged component 1 is retained on the building structure, the original support continues, thereby avoiding the impact on the entire building structure when the component is removed as a whole, and the safety is stronger. Among them, before peeling off the carbonized layer 2, the movable load on the floor should be reduced, and it is verified whether the damaged component 1 needs additional support to ensure safety according to the actual load of the floor. When bonding the first bonding surface 11 and the second bonding surface 31, an adhesive can be applied on the first bonding surface 11 and / or the second bonding surface to form an adhesive layer 4, and then the second bonding surface 31 is placed on the first bonding surface 11 until the adhesive layer 4 solidifies. In addition, the carbonized layer in the present invention may include all or part of the carbonized material on the damaged component, and the carbonized layer may also include a part of the damaged component that is not damaged but has been removed.

[0034] In a preferred implementation manner of this embodiment, before the step of stripping the carbonized layer 2, it also includes determining the stripping thickness: measuring and calculating the thickness of the carbonized material at multiple positions on the damaged side of the damaged component 1, drawing a carbonized surface on the three-dimensional model of the damaged component 1 according to the thickness of the carbonized material at each position, the carbonized surface being the interface between the carbonized material and the non-damaged part of the damaged component 1, and determining the thickness of the damaged component 1 to be stripped according to the depth of the carbonized surface in the damaged component 1. Since the thickness of the carbonized layer is not uniform, the shape and thickness of the carbonized layer formed by all the carbonized materials are calculated by measuring the thickness of the carbonized materials at multiple positions to determine the specific thickness of the carbonized layer that needs to be removed. Taking the component as a rectangular floor slab as an example, when the overall thickness of all the carbonized materials is determined to be less than 40% of the thickness of the damaged component 1, all the carbonized materials (carbonized layer 2) are removed and the surface of the damaged component is flattened. When the overall thickness of all the carbonized materials is determined to be greater than 40% of the thickness of the damaged component 1, only the carbonized layer 2 with a thickness within 40% is peeled off, and the remaining carbonized materials are retained on the remaining damaged component, and multiple remaining carbonized areas are formed on the first bonding surface 11 after the carbonized layer is peeled off. The sum of the areas of the remaining carbonized areas should be less than 5% of the area of ​​the first bonding surface 11, and the circumscribed circular diameter of the remaining single carbonized area should be less than the smaller value of 2 times the component thickness and 1 / 8 of the component width. It can be determined that the damaged component can continue to carry out subsequent repair work. A plurality of measuring positions can be determined in a dot matrix on the carbonized layer 2 and the thickness of the carbonized material at the plurality of measuring positions can be determined. The dot matrix is ​​preferably a rectangular dot matrix, and the distance between each point is between 2 times and 5 times the component thickness.

[0035] In a preferred implementation of the present embodiment, the step of bonding the filling member 3 further includes: after the first bonding surface 11 and the second bonding surface 31 are bonded and fixed, applying pressure to the filling member 3 so that the filling member 3 is pressed tightly against the adhesive. By applying pressure to the filling member 3, the firmness of the adhesion between the filling member 3 and the damaged component 1 can be improved, thereby improving the bearing capacity of the repaired component. In the process of applying pressure, the adhesive that is squeezed and overflowed between the damaged component 1 and the filling member 3 should be removed in time.

[0036] In a preferred implementation manner of this embodiment, in the step of bonding the filling member 3: Figure 4As shown, pressure is applied to the filling member 3 by the self-tapping screws 6, and multiple self-tapping screws 6 are driven into the filling member 3 from the side of the filling member 3 away from the damaged member 1, and a part of each self-tapping screw 6 is driven into the damaged member 1. When selecting a method of applying pressure, the self-tapping screws 6 can more conveniently apply pressure to the filling member 3, and compared with the method of placing a heavy object on the filling member 3 to apply pressure, it can not only meet the need for pressurization in the horizontal or vertical direction, but also avoid the negative impact of the weight of the heavy object on the damaged building. Among them, the spacing between two adjacent self-tapping screws 6 should be 100mm-150mm.

[0037] In a preferred implementation manner of this embodiment, when driving the self-tapping screw 6, the self-tapping screw 6 in the middle of the filling member 3 is driven first, and then the self-tapping screw 6 at the edge of the filling member 3 is driven. Driving the self-tapping screw 6 in the middle of the filling member 3 first, and then the self-tapping screw 6 at the edge can avoid local arching and poor fit.

[0038] In a preferred implementation of the present embodiment, after the step of bonding the filling component 3 is completed, it also includes: fire prevention treatment: removing the respective tapping screws 6, and performing fire prevention sealing on the nail holes formed by removing the self-tapping screws 6. Since the self-tapping screws 6 are made of metal and have strong thermal conductivity, if they are retained in the repaired component, they will increase the safety hazard in the event of a fire. After the self-tapping screws 6 are removed, the heat conduction of the self-tapping screws 6 can be avoided, thereby improving the fire prevention performance of the repaired component.

[0039] In a preferred implementation of this embodiment, Figure 1 As shown, the step of determining the peeling thickness also includes: using a drill rod of a drillable resistance detector to drill into and penetrate the damaged component 1 from multiple positions on the non-damaged side of the damaged component 1, and calculating the thickness of the carbonized material at multiple positions according to the change in resistance. Since there is a large difference in resistance between the undamaged wooden component and the carbonized material, the use of the drillable resistance detector 5 can accurately determine the thickness of the carbonized material through the change in resistance. When measuring, a line graph of resistance versus the drilling depth of the drillable resistance detector 5 is drawn based on the measurement data of the drillable resistance detector 5. In the graph, the thickness of the component is t, the idle distance of the drillable resistance detector 5 before drilling is s, and when the resistance drops sharply, the drilling depth of the drillable resistance detector 5 is t0, then the thickness of the undamaged wood is t1=t0-s, the thickness of the carbonized wood is t2=t-t1, and the thickness of the carbonized material at the drilling position is t2=t-t1.

[0040] In a preferred implementation of this embodiment, the damaged side of the damaged component 1 is planed multiple times to peel off the carbonized layer 2, and the thickness of each planing is 5 mm to 8 mm. The thickness of each planing is between 5 mm and 8 mm, and the planing thickness is reasonable, which can limit the vibration of the structure and reduce the surface defects of the damaged component 1. After the planing is completed, a first bonding surface 11 is formed on the surface of the damaged component 1, and a laser rangefinder can be used to measure the flatness of the first bonding surface 11.

[0041] In a preferred implementation of the present embodiment, the adhesive layer 4 is formed by coating with a gap-filling phenol resorcinol formaldehyde adhesive. Since the surface processed on site cannot reach the flatness of factory processing, a gap will appear between the first adhesive surface 11 and the second adhesive surface 31. The gap-filling phenol resorcinol formaldehyde adhesive can effectively fill the gap between the first adhesive surface 11 and the second adhesive surface 31. Moreover, the adhesive is resistant to high temperatures and can prevent the repaired component from being delaminated due to damage to the adhesive layer 4 during a fire.

[0042] In order to minimize the strength loss of the repaired component, in a preferred implementation of this embodiment, the strength grade of the filling component 3 is not less than the strength grade of the damaged component 1 .

[0043] Embodiment 2

[0044] A CLT floor was severely damaged after a major fire, and was repaired using the post-fire wooden floor repair method provided by the present invention:

[0045] Before the CLT floor was damaged, it was composed of five layers of 35mm thick plies, and the standard value of the nominal bending strength of the 35mm ply is 28MPa.

[0046] After a major fire, the average charring depth of a CLT floor was measured to be 50 mm.

[0047] Completely peel off a 35mm layer of ply on the damaged side of the CLT floor, and then plane and peel off the next layer of ply by 20mm, ensuring that the remaining carbonized part after peeling is less than 5% of the floor area. The circumscribed circular diameter of a single carbonized area should be less than the smaller value of 2 times the floor thickness and 1 / 8 the floor width. At the same time, use a distance meter to measure the distance to ensure the surface is flat.

[0048] 75mm thick glued laminated wood is selected as the filling member 3, and the nominal bending strength standard value is 32MPa.

[0049] Choose phenol resorcinol formaldehyde adhesive, which can effectively fill the gap of 2mm and has good fire resistance. Use double-threaded wood screws with a diameter of 6.5mm and a length of 130mm, and nail them in at intervals of 100mm along the wood grain direction of the glued wood to provide pressure.

[0050] To prevent heat conduction in a future fire, remove double-threaded wood screws after glue bonding is complete.

[0051] The four-point bending test method was used to carry out loading tests on the reinforced CLT floor slabs. The test results showed that compared with the performance provided by the original CLT manufacturer, the reinforced CLT floor slabs exhibited stronger bending stiffness and bending strength, as shown in Table 1.

[0052] Table 1 Comparison of bending strength and flexural strength before and after reinforcement

[0053] Strength index Initial CLT board Reinforced CLT board Comparison Bending stiffness <![CDATA[4240kN·m 2 / m]]> <![CDATA[5768kN·m 2 / m]]> Increase Bending Strength 125kN·m / m >123kN·m / m Remain the same or increase

[0054] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for repairing a wooden floor after a fire, characterized in that: The following steps are involved: Peeling off the carbonized layer: peeling off the carbonized layer on the damaged component to form a first bonding surface on the damaged side of the remaining damaged component; Bonding the filling component: The side of the filling component used to contact the damaged component is the second bonding surface, and the first bonding surface and the second bonding surface are bonded and fixed by an adhesive.

2. The method for repairing a wooden floor after a fire according to claim 1, characterized in that: Before the step of stripping the carbonized layer, the method also includes determining the stripping thickness: measuring and calculating the thickness of the carbonized material at multiple positions on the damaged side of the damaged component, drawing a carbonized surface on the three-dimensional model of the damaged component according to the thickness of the carbonized material at each position, the carbonized surface being the interface between the carbonized material and the non-damaged part of the damaged component, and determining the thickness of the damaged component to be stripped according to the depth of the carbonized surface in the damaged component.

3. The method for repairing a wooden floor after a fire according to claim 1, characterized in that: The step of bonding the filling member further includes: after the first adhesive surface and the second adhesive surface are bonded and fixed, applying pressure to the filling member so that the filling member is pressed tightly against the adhesive.

4. The method for repairing a wooden floor after a fire according to claim 3, characterized in that: In the step of bonding the filling member: applying pressure to the filling member by means of self-tapping screws, driving a plurality of the self-tapping screws into the filling member from the side of the filling member away from the damaged member, and driving a portion of each of the self-tapping screws into the damaged member.

5. The method for repairing a wooden floor after a fire according to claim 4, characterized in that: When driving the self-tapping screws, first drive the self-tapping screws in the middle of the filling component, and then drive the self-tapping screws at the edge of the filling component.

6. The method for repairing a wooden floor after a fire according to claim 4, characterized in that: After the step of bonding and filling the components is completed, the method further includes: fire prevention treatment: removing each of the self-tapping screws, and performing fire prevention sealing on the nail holes formed after removing the self-tapping screws.

7. The method for repairing a wooden floor after a fire according to claim 2, characterized in that: The step of determining the peeling thickness also includes: using a drill rod capable of drilling into a resistance detector to drill into and penetrate the damaged component from multiple locations on the non-damaged side of the damaged component, and inferring the thickness of the carbonized material at the multiple locations based on changes in resistance.

8. The method for repairing a wooden floor after a fire according to claim 1, characterized in that: In the step of peeling off the carbonized layer, the damaged side of the damaged component is planed multiple times to peel off the carbonized layer, and the thickness of each planing is 5 mm to 8 mm.

9. The method for repairing a wooden floor after a fire according to claim 1, characterized in that: The adhesive is a gap-filling phenol resorcinol formaldehyde adhesive.

10. The method for repairing a wooden floor after a fire according to claim 1, characterized in that: The strength grade of the filling component is not less than the strength grade of the damaged component.

Images