Rapid and lossless existing grid roof updating and reconstruction method

Abstract

The invention relates to the technical field of steel structure reinforcement, in particular to a rapid and lossless existing grid roof updating and reconstruction method, which comprises the following steps of: selecting whether to utilize an existing purline or not according to the current conditions of the existing purline, including strength, rigidity and use durability; when the existing purlins are used, the existing purlins are used as secondary purlins, and the existing purlins, the newly-added main purlins and the newly-added secondary purlins serve as an integral structure to jointly bear the upper load; when the existing purlin is not used, the newly-added main purlin and the newly-added secondary purlin bear the upper load, and the existing purlin does not bear the upper load; and if the existing steel pipe does not meet the requirement, the existing steel pipe is externally wrapped and reinforced. The method has the advantages that the bearing capacity of the steel grid structure is remarkably improved, and the design requirement of roof dead load is met; the structure is simple and reasonable, on-site installation is lossless and rapid, the newly-added main purlin can be stably installed, and the newly-added secondary purlin can be further installed; the prefabricated degree is high, the construction efficiency is high, modular design can be conducted according to various working conditions, and the method is suitable for popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of steel structure reinforcement, and particularly relates to a method for rapidly and non-destructively renovating and upgrading an existing grid roof. Background Art

[0002] The current roofs of elevated rail transit stations are mostly steel grid structures, and the design limit of the roof dead load is 0.2 to 0.3 kN / m 2 , and this part of the load includes all the enclosure structures such as purlin supports, purlins, roof panels and their connectors above the grid spherical nodes.

[0003] Currently, purlins are arranged on the spherical nodes along the longitudinal direction of the station for the existing elevated rail transit stations, and single-layer color steel plates are arranged on the purlins. The actual roof dead load is about 0.1 kN / m 2 , meeting the design requirements.

[0004] However, when renovating the existing elevated rail transit stations, for example, replacing the roof panel with an aluminum-magnesium-manganese plate according to the renovation requirements, the self-weight calculated according to the roof panel structure is about 0.25 to 0.30 kN / m 2 , and the situation of insufficient strength or stability of the existing grid structure and existing purlins may occur. At the same time, subway operation cannot be interrupted, and all construction must be completed within the skylight points. However, the number of skylight points per week is limited, and multi-party cooperation in construction is required. Moreover, after construction, the grid needs to be covered and cannot be exposed to affect operation. In addition, the skylight points are all in the early morning, and there are noise control requirements.

[0005] Therefore, how to solve the above problems is a technical problem that the existing technology urgently needs to solve. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for rapidly and non-destructively renovating and upgrading an existing grid roof according to the deficiencies of the above-mentioned existing technology. By setting a support structure at the position of the existing grid spherical nodes to cooperate with the installation of new main purlins, the non-destructive and rapid installation of the new main purlins is realized. Further, by installing the new main purlins and new secondary purlins, the bearing capacity of the steel grid roof structure is increased, so as to meet the renovation requirements.

[0007] The purpose of the present invention is achieved by the following technical solutions: A method for rapidly and non-destructively renovating and upgrading an existing grid roof, which is used to improve the bearing capacity of the existing grid roof system. The existing grid roof purlin system includes existing purlins, and each of the existing purlins is installed on the grid spherical nodes with existing purlin supports. The grid spherical nodes are connected by existing steel pipes to form an overall load-bearing structure. The characteristics of the design method include: According to the current situation of the existing purlins, including strength, stiffness and service durability, select whether to utilize the existing purlins; When using the existing purlins, a support structure is provided on the existing purlin bracket, and a new main purlin perpendicular to the line direction and a new secondary purlin parallel to the line direction are provided on the support structure. The new main purlin and the new secondary purlin are connected, and the bearing surface elevations of the new main purlin and the new secondary purlin are equal to the bearing surface elevation of the existing purlin. The existing purlin is used as a secondary purlin, and the existing purlin, the new main purlin, and the new secondary purlin jointly bear the upper load as an integral structure; When not using the existing purlins, a support structure is provided on the existing purlin bracket, and a new main purlin perpendicular to the line direction and a new secondary purlin parallel to the line direction are provided on the support structure. The new main purlin and the new secondary purlin are connected, and the bearing surface elevations of the new main purlin and the new secondary purlin are higher than the bearing surface elevation of the existing purlin. The new main purlin and the new secondary purlin bear the upper load, and the existing purlin does not bear the upper load; According to the increased load of the new main purlin and the new secondary purlin, structural inspection and appraisal are carried out; If the existing steel pipe does not meet the requirements, the existing steel pipe is strengthened by external wrapping.

[0008] When using the existing purlins, the new secondary purlins and the existing purlins are arranged at equal intervals in the direction perpendicular to the line.

[0009] When not using the existing purlins, the new secondary purlins are arranged at equal intervals in the direction perpendicular to the line.

[0010] The support structure has a connecting plate, and connecting holes are provided on the connecting plate. The new main purlin is supported on the connecting plate, and a simple support connection is formed between the new main purlin and the connecting plate through a connecting piece screwed into the connecting hole.

[0011] The support structure includes two purlin bracket supports with the same structure. The two purlin bracket supports are connected and fixed by connecting pieces and are assembled to form a clamping space matching the existing purlin bracket of the grid ball node, so that the support structure clamps around the existing purlin bracket, and the connecting plate is arranged on the purlin bracket support.

[0012] A shear stiffening rib plate is extended and arranged between the purlin bracket support and the connecting plate, and the shear stiffening rib plate is located below the connecting plate.

[0013] A new outer pipe formed by splicing two semi-circular pipes is arranged around the existing steel pipe. The new outer pipe is sleeved around the existing steel pipe, and a certain gap is left between the new outer pipe and the existing steel pipe. A filling material is poured into the gap; the end of the new outer pipe is enclosed and welded with the existing gusset plate by fillet welding.

[0014] The two semi-circular pipes are fixedly connected into an integral structure through bolts arranged on the connecting plate.

[0015] The two semi-circular pipes are fixedly connected by welding into an integral structure.

[0016] Perfusion holes are reserved at both ends and the middle of the semi-circular pipe, and the perfusion holes are closed after filling the filling material.

[0017] The advantages of the present invention are as follows: significantly improving the bearing capacity of the steel grid structure and meeting the design requirements of the roof dead load; the structure is simple and reasonable, the on-site installation is fast without damage and the new main purlins can be stably installed and the new secondary purlins can be further installed; the prefabrication degree is high, the construction efficiency is high, modular design can be carried out for various working conditions, and it is suitable for popularization. Description of the Drawings

[0018] Figure 1 is the flowchart of the method of the present invention; Figure 2 is the layout schematic diagram of the existing purlins; Figure 3 is the layout schematic diagram when using the existing purlins in the present invention; Figure 4 is the layout schematic diagram when not using the existing purlins in the present invention; Figure 5 is the structural schematic diagram of the present invention; Figure 6 is the node schematic diagram of the present invention; Figure 7 is the structural schematic diagram of the support structure in the present invention; Figure 8 is the cross-sectional view of the first steel pipe reinforcement method in the present invention; Figure 9 is the longitudinal view of the first steel pipe reinforcement method in the present invention; Figure 10 is the cross-sectional view of the second steel pipe reinforcement method in the present invention; Figure 11 is the longitudinal view of the second steel pipe reinforcement method in the present invention. Detailed Embodiments

[0019] The features of the present invention and other related features are further described in detail below with reference to the drawings through embodiments for the understanding of those skilled in the same industry: As Figures 1-11As shown in the figure, the reference numerals 1-20 in the figure respectively represent: the first purlin support bracket 1, the second purlin support bracket 2, the connecting plate 3, the connecting hole 4, the wing plate 5, the bolt fixing hole 6, the shear stiffening rib plate 7, the existing purlin 8, the space grid spherical node 9, the support structure 10, the existing purlin support 11, the newly added main purlin 12, the newly added secondary purlin 13, the existing steel pipe 14, the newly added outer pipe 15, the connecting plate and bolts 16, the epoxy injection glue 17, the fillet weld 18, the existing gusset plate 19, and the weld 20.

[0020] Example: In combination with Figure 1 and Figure 5 As shown, in this embodiment, the design method for quickly and non-destructively transforming the existing space grid roof purlin system is used for the transformation condition where the bearing capacity of the existing purlin 8 does not meet the design requirements of the upper dead load. The existing purlin 8 is supported on the space grid spherical node 9 with the existing purlin support 11.

[0021] The design method in this embodiment includes the following steps: 1) According to the current situation of the existing purlin 8, including strength, stiffness, and service durability, select whether to utilize the existing purlin 8. According to the current situation of the existing purlin 8, this embodiment is divided into two cases: utilizing the existing purlin 8 and not utilizing the existing purlin 8. However, in the actual design process, if the current situation of the existing purlin 8 is good and there is a possibility of reinforcement, then the situation of utilizing the existing purlin 8 can be considered as much as possible and corresponding measures can be taken to repair or reinforce the existing purlin 8 that does not meet the usage conditions.

[0022] 2) When utilizing the existing purlin 8, a support structure 10 is set on the existing purlin support 11.

[0023] As Figure 7 shown, the support structure 10 includes a first purlin support bracket 1 and a second purlin support bracket 2. Both purlin support brackets have a semi-circular structure. Wing plates 5 extending outward are respectively arranged at the side positions of the semi-circular structure, and bolt fixing holes 6 are respectively opened on the wing plates 5; when the first purlin support bracket 1 and the second purlin support bracket 2 are spliced, the bolt fixing holes on their respective wing plates are aligned and bolts are screwed in to realize the fixation of the first purlin support bracket 1 and the second purlin support bracket 2. At this time, the clamping area formed by the splicing of the first purlin support bracket 1 and the second purlin support bracket 2 is in conformity with the outer contour shape and size of the existing purlin support 11, so that the support structure 10 assembled by the first purlin support bracket 1 and the second purlin support bracket 2 can be clamped and fixed around the existing purlin support 11 without damage and quickly.

[0024] In combination with Figure 3 and Figure 5 As shown, a newly added main purlin 12 ( Figure 2 the cyan part and the green part in Figure 2The magenta parts), the newly added main purlins 12 and the newly added secondary purlins 13 are fixedly connected, and the elevation of the bearing surfaces of the newly added main purlins 12 and the newly added secondary purlins 13 is equal to the elevation of the bearing surface of the existing purlins 8. The existing purlins 8 are used as secondary purlins, and the existing purlins 8, the newly added main purlins 12, and the newly added secondary purlins 13 jointly bear the upper load as an integral structure.

[0025] When using the existing purlins 8, each newly added secondary purlin 13 ( Figure 2 the magenta parts) and each existing purlin 8 ( Figure 2 the red parts) are arranged at equal intervals along the direction perpendicular to the line. At this time, compared with the situation of only arranging the existing purlins 8 before the transformation, the span of the roof slab is reduced by arranging the newly added secondary purlins 13, and the load area of the existing purlins 8 is correspondingly reduced, thereby realizing the improvement of the bearing capacity. During the whole transformation construction process, since the support structure 10 can be installed quickly and without damage, and the newly added main purlins 12 and the newly added secondary purlins 13 can be prefabricated components and welded and connected on the ground, the transformation process can be carried out without noise during a very short skylight point.

[0026] In this embodiment, in combination with Figure 5 and Figure 7 As shown, on the upper parts of the semi-circular structures of the first purlin support bracket 1 and the second purlin support bracket 2, connecting plates 3 extending outward are respectively provided, and the connecting plates 3 are used for stably supporting the newly added main purlins 12 carried above. In this embodiment, two connecting holes 4 are opened on the connecting plates 3, and the two connecting holes 4 can be simply supported and connected to the newly added main purlins 12 above through connecting pieces such as bolts, so as to further increase the structural stability and safety of the newly added main purlins 12 while ensuring that the newly added main purlins 12 can be effectively and stably supported by the connecting plates 3, and further ensure the structural strength of the newly added secondary purlins 13.

[0027] In this embodiment, in order to ensure the structural strength and stability of the connecting plates 3, shear stiffening ribs 7 are respectively arranged below the connecting plates 3 of the first purlin support bracket 1 and the second purlin support bracket 2. The shear stiffening ribs 7 extend along the extending direction of the connecting plates 3 and are of equal length, and the load-bearing performance of the connecting plates 3 is increased through the shear stiffening ribs 7.

[0028] 3) When not using the existing purlins, the support structure 10 is also arranged on the existing purlin supports 11.

[0029] As Figure 4 shown, on the support structure 10, newly added main purlins 12 ( Figure 4 the cyan part and the green part) in the direction perpendicular to the line and newly added secondary purlins 13 ( Figure 4The magenta part), the newly added main purlin 12 and the newly added secondary purlin 13 are fixedly connected. The bearing surface elevation of the newly added main purlin 12 and the newly added secondary purlin 13 is higher than the bearing surface elevation of the existing purlin 8. At this time, the newly added main purlin 12 and the newly added secondary purlin 13 bear the upper load, and the existing purlin 8 does not bear the upper load.

[0030] When the existing purlin 8 is not utilized, the newly added secondary purlins 13 are arranged at equal intervals along the vertical line direction.

[0031] 4) After the newly added main purlin 12 and the newly added secondary purlin 13 are newly set, the roof load increases. Therefore, structural members need to be structurally tested and identified and structurally strengthened; if the existing steel pipe 145 does not meet the requirements, effective supports need to be set around the replaced member to restore the state before the member is loaded, and then the member can be unscrewed and replaced, which has a greater impact on the operation of the station; and the space frame is a whole stressed structure, and removing one member will affect the overall stress state, and in severe cases, safety problems will occur and the space frame will collapse.

[0032] Therefore, in this embodiment, a reinforcement scheme that has no impact on the original structure is adopted to avoid disassembling and replacing the space frame members.

[0033] As Figure 8 shown, the reinforcement structure in the embodiment includes a newly added outer pipe 15 sleeved outside the existing steel pipe 14. The newly added outer pipe 15 is formed by bolt connection and splicing of two semi-circular pipes. Connecting plates and bolts 16 are respectively arranged on the upper and lower sides of the semi-circular pipes. Through the butt joint of the bolts, the two semi-circular pipes are connected to form an integral structure and are clamped around the existing steel pipe 14; the connecting plates and bolts 16 are evenly spaced along the longitudinal direction of the semi-circular pipes to ensure the connection performance between the two semi-circular pipes. The shapes and sizes of the two semi-circular pipes match and fit with the shape and size of the existing steel pipe 14, and glue injection holes are reserved at both ends and in the middle.

[0034] A certain gap is left between the newly added outer pipe 15 and the existing steel pipe 14, and epoxy injection glue 17 is filled in this gap. Through the epoxy injection glue 17, the newly added outer pipe 15 and the existing steel pipe 14 are longitudinally connected into an integral structure, so that the existing steel pipe 14 and the newly added outer pipe 15 work together.

[0035] In this embodiment, through the epoxy injection glue 17, the existing steel pipe 14 and the newly added outer pipe 15 are connected to form an integral stressed structure, and the two work together, thereby improving the structural performance of the existing steel pipe 14, especially improving the buckling limit of the member, and further increasing the support bearing capacity of the steel roof truss.

[0036] In this embodiment, in order to make the newly added outer pipe 15 participate in the stress of the steel roof truss, the newly added outer pipe 15 and the existing gusset plate are enclosed and welded by fillet welding.

[0037] When this embodiment is specifically applied, it includes the following process: According to the calculation results, steel pipes with a diameter and wall thickness not less than those required for the calculation are used (there is a gap of several millimeters between the inner wall and the original member). The length of the existing steel pipe 14 is measured on-site. The steel pipe is cut into two semi-circular steel pipes, and connection plates are set. Holes are arranged on the plates at a certain interval. After sleeving on the existing steel pipe 14, the two semi-circular steel pipes are connected by bolts to form a new outer pipe 15 around the existing steel pipe 14, and the new outer pipe 2 is welded to the existing gusset plate; quick-drying glue is injected at the edge of the bolt connection to block the gap, and glue injection holes are reserved at both ends and in the middle of the member. The gap between the new outer pipe 15 and the existing gusset plate is filled with epoxy grouting 17.

[0038] In this way, the original structure can be strengthened while the original structure continues to be in service. After the epoxy grouting 4 is filled, the inner and outer walls can work together to improve the buckling limit of the member and enhance the strength of the member at the same time.

[0039] In this embodiment, in addition to bolt connection between the two semi-circular steel pipes, butt welding with a groove can also be directly used, with symmetric and intermittent welding to form a weld 20 between them.

[0040] Although the above embodiments have described in detail the concept and embodiments of the object of the present invention with reference to the drawings, those of ordinary skill in the art can recognize that various improvements and transformations can still be made to the present invention without departing from the scope defined by the claims, so they will not be elaborated here one by one.

Claims

1. A rapid and non-destructive method for renovating existing grid roofs, which is used to improve the bearing capacity of the existing grid roof system. The existing purlin system of the grid roof includes existing purlins, and each of the existing purlins is installed on the grid ball joints with existing purlin supports. The grid ball joints are connected by existing steel pipes to form an integral load-bearing structure. It is characterized in that: The design method includes: Select whether to utilize the existing purlin according to the current situation of the existing purlin, including strength, stiffness, and service durability; When utilizing the existing purlin, a support structure is set on the existing purlin bracket, a new main purlin perpendicular to the line direction and a new secondary purlin parallel to the line direction are set on the support structure, the new main purlin and the new secondary purlin are connected, the bearing surface elevation of the new main purlin and the new secondary purlin is equal to the bearing surface elevation of the existing purlin, the existing purlin is used as a secondary purlin, and the existing purlin, the new main purlin, and the new secondary purlin jointly bear the upper load as an integral structure; When not utilizing the existing purlin, a support structure is set on the existing purlin bracket, a new main purlin perpendicular to the line direction and a new secondary purlin parallel to the line direction are set on the support structure, the new main purlin and the new secondary purlin are connected, the bearing surface elevation of the new main purlin and the new secondary purlin is higher than the bearing surface elevation of the existing purlin, the new main purlin and the new secondary purlin bear the upper load, and the existing purlin does not bear the upper load; Conduct structural inspection and appraisal according to the increased load of the new main purlin and the new secondary purlin; If the existing steel pipe does not meet the requirements, the existing steel pipe is externally wrapped and strengthened.

2. A rapid and non-destructive method for renovating an existing grid roof according to claim 1, characterized in that: When utilizing the existing purlin, each new secondary purlin and each existing purlin are arranged at equal intervals in the direction perpendicular to the line.

3. A rapid and non-destructive method for renovating an existing grid roof according to claim 1, characterized in that: When not utilizing the existing purlin, each new secondary purlin is arranged at equal intervals in the direction perpendicular to the line.

4. A rapid and non-destructive method for renovating an existing grid roof according to claim 1, characterized in that: The support structure has a connecting plate, and connecting holes are opened on the connecting plate. The new main purlin is supported on the connecting plate, and a simple support connection is formed between the new main purlin and the connecting plate through a connecting piece screwed into the connecting hole.

5. A rapid and non-destructive method for renovating an existing grid roof according to claim 4, characterized in that: The support structure includes two purlin bracket supports with the same structure. The two purlin bracket supports are connected and fixed through connecting pieces and assembled to form a clamping space matching the existing purlin of the grid ball joint, so that the support structure clamps around the existing purlin, and the connecting plate is arranged on the purlin bracket support.

6. A method for rapid and non-destructive renovation of existing grid roofs according to claim 5, characterized in that: A shear stiffening rib plate is extended and arranged between the purlin bracket support and the connecting plate, and the shear stiffening rib plate is located below the connecting plate.

7. A method for rapid and non-destructive renovation of existing grid roofs according to claim 1, characterized in that: A new outer pipe composed of two semi-circular pipes is arranged around the existing steel pipe. The new outer pipe is sleeved around the existing steel pipe, and a certain gap is left between the new outer pipe and the existing steel pipe. A filling material is poured into the gap; the end of the new outer pipe and the existing gusset plate are enclosed and welded by fillet welding.

8. A rapid and non-destructive method for renovating an existing grid roof according to claim 7, characterized in that: The two semi-circular pipes are fixedly connected into an integral structure through bolts arranged on the connecting plate.

9. A method for rapid and non-destructive renovation of existing grid roofs according to claim 7, characterized in that: The two semi-circular pipes are fixedly welded into an integral structure.

10. A method for rapid and non-destructive renovation of existing grid roofs according to claim 7, characterized in that: Pouring holes are reserved at both ends and the middle of the semi-circular pipe, and the pouring holes are closed after pouring the filling material.

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