Temporary reinforcing structure for post-pouring belt and construction method thereof

Abstract

The application relates to the technical field of building construction, and discloses a temporary reinforcing structure for a post-pouring belt vehicle and a construction method thereof. The temporary reinforcing structure comprises the following steps: verifying the strength and the slab surface state of the poured top slab on both sides of the post-pouring belt, determining the vehicle running direction, the wheel trace line and the temporary reinforcing range, forming an upper bearing area on both sides of the post-pouring belt, and determining the corresponding lower supporting area below the upper bearing area; installing a lower alignment and back-up system and carrying out pre-pressing locking, then installing an upper belt-crossing load distribution system composed of a bearing pad beam, a longitudinal distribution beam and a vehicle bridge deck above the post-pouring belt, and carrying out trial running monitoring after setting a wheel trace limiting channel. The method makes the vehicle wheel load transmitted to the solid area of the poured top slab on both sides after being distributed by the upper belt-crossing load distribution system, and the load is supported by the lower alignment and back-up system, so that the local compression of the post-pouring belt edge and the supporting lagging stress are reduced, and the safety of the temporary post-pouring belt vehicle is improved.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to a temporary reinforcement structure for vehicles traveling on post-cast strips and its construction method. Background Technology

[0002] Post-cast strips are widely used in concrete structures such as basement roofs and garage roofs to release shrinkage deformation during construction or to adjust later structural connections. During construction, due to material transportation, equipment relocation, and temporary road layout, vehicles sometimes need to cross post-cast strip areas that are not yet closed or ready for direct passage.

[0003] In current construction practices, independent support systems are typically maintained on both sides of the post-cast strip, or a back-support frame is added under the top slab, and steel plates, structural steel, or a temporary bridge deck are laid above the post-cast strip for vehicle passage. This approach can improve the local load-bearing capacity of the top slab to some extent, but it focuses more on the lower support or the upper paved components themselves, and the correspondence between vehicle wheel loads, upper bearing positions, and lower back-support positions is not clear enough.

[0004] When a vehicle crosses the post-cast strip, the wheel load will move near the edge of the post-cast strip as the vehicle travels. If the upper load is not distributed to the solid areas of the already poured top slab on both sides beforehand, and the lower support is not aligned with the bearing position and tightened in advance, the vehicle load is likely to cause local pressure and deflection on the edge of the post-cast strip, resulting in unstable force transmission during temporary vehicle travel. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a temporary reinforcement structure for post-cast strip trolleys and its construction method, thereby solving the technical problems existing in the prior art.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0007] A construction method for a temporary reinforcement structure for a vehicle traveling along a post-cast strip includes the following steps:

[0008] S1: Verify the concrete strength and surface condition of the poured top slabs on both sides of the post-pouring strip to ensure that the poured top slabs on both sides of the post-pouring strip meet the reinforcement construction conditions before temporary vehicle passage.

[0009] S2: Based on the structural drawings of the basement roof slab, the location of the post-cast strip, and the vehicle traffic route, determine the direction of travel, wheel track, and temporary reinforcement range for vehicles crossing the post-cast strip;

[0010] S3: Lay out lines on the cast-in-place slabs on both sides of the post-cast strip to form the first upper bearing area and the second upper bearing area, so that the first upper bearing area and the second upper bearing area are located on both sides of the post-cast strip, and both the first upper bearing area and the second upper bearing area are located within the solid area of ​​the cast-in-place slab.

[0011] S4: Determine a first lower support area and a second lower support area below the first upper pressure area and the second upper pressure area respectively, so that the first lower support area is located within the vertical projection range of the first upper pressure area, and the second lower support area is located within the vertical projection range of the second upper pressure area.

[0012] S5: Install the lower alignment and backing system in the first and second lower support areas respectively, and make the lower alignment and backing system press against the bottom surface of the cast-in-place top slab on both sides of the post-cast strip.

[0013] S6: Perform pre-compression adjustment on the lower alignment and back-top system, and lock the support height of the lower alignment and back-top system after the pre-compression adjustment is completed;

[0014] S7: Install an upper cross-belt load distribution system between the first upper pressure zone and the second upper pressure zone, so that the upper cross-belt load distribution system spans above the post-cast strip, and the vehicle wheel load is transferred to the first upper pressure zone and the second upper pressure zone through the upper cross-belt load distribution system.

[0015] S8: Set a wheel track limiting channel on the upper crossbelt load distribution system so that the vehicle wheel track line is located above the longitudinal load distribution position of the upper crossbelt load distribution system;

[0016] S9: Conduct trial passage and test the deformation status of the cast-in-place top slabs on both sides of the post-cast strip and the lower alignment back jacking system. When the detected deformation value does not exceed the control value determined by the construction calculation, limited vehicle passage is opened.

[0017] Preferably, when determining the temporary reinforcement range, the projection range of the vehicle wheel track line in the length direction of the post-cast strip is used as the basis, and reinforcement extension sections are formed by extending outward along the vehicle entry side and the vehicle exit side respectively. The reinforcement extension sections are used to cover the wheel load transition area before and after the front or rear wheels of the vehicle approach the post-cast strip.

[0018] Preferably, after the first and second upper pressure zones are laid out, pressure bearing beams are laid in the first and second upper pressure zones respectively. The length direction of the pressure bearing beams is arranged along the length direction of the post-cast strip, and the bottom surface of the pressure bearing beams is completely supported on the cast-in-place top slabs on both sides of the post-cast strip.

[0019] Preferably, the lower alignment and jacking system includes a lower support beam, multiple adjustable supports, and connecting rods. When installing the lower alignment and jacking system, the lower support beam is first arranged within the vertical projection range of the corresponding upper pressure zone, and then multiple adjustable supports are supported below the lower support beam. Subsequently, adjacent adjustable supports are connected by connecting rods.

[0020] Preferably, when pre-compressing the lower alignment and jacking system, multiple adjustable supports are adjusted sequentially so that the lower support beam gradually presses against the bottom surface of the poured top slab from the middle to both ends. After the lower support beam and the bottom surface of the poured top slab form a continuous contact, the support height of the multiple adjustable supports is locked.

[0021] Preferably, the connecting rod includes a longitudinal connecting rod arranged along the length direction of the post-pouring strip and a transverse connecting rod arranged perpendicular to the length direction of the post-pouring strip. The longitudinal connecting rod connects adjacent adjustable supports located on the same side of the post-pouring strip, and the transverse connecting rod connects adjacent adjustable supports located on both sides of the post-pouring strip.

[0022] Preferably, the upper cross-belt load distribution system includes a vehicular bridge deck, a longitudinal distribution beam, a first bearing pad beam, and a second bearing pad beam. When installing the upper cross-belt load distribution system, the first bearing pad beam and the second bearing pad beam are first installed in the first upper bearing area and the second upper bearing area, respectively. Then, the longitudinal distribution beam is straddled between the first bearing pad beam and the second bearing pad beam. Subsequently, the vehicular bridge deck is laid on the longitudinal distribution beam.

[0023] Preferably, the longitudinal distribution beam includes a first longitudinal beam and a second longitudinal beam, which are respectively arranged below the wheel tracks on both sides of the vehicle, so that the left and right wheel loads of the vehicle are transferred to the first bearing pad beam and the second bearing pad beam through the first longitudinal beam and the second longitudinal beam, respectively.

[0024] Preferably, when setting up the wheel track limiting channel, limiting beams are installed on both sides of the upper crossbelt load distribution system, and a channel for vehicles to pass is formed between the two limiting beams. The channel is located above the longitudinal load distribution position of the upper crossbelt load distribution system.

[0025] Preferably, during the trial run, monitoring points are set at the bottom surface of the cast-in-place top slab on both sides of the post-cast strip, at the lower support beam and at the adjustable support components. The vehicle passes through the upper cross-strip load-sharing system at the speed determined by the construction calculation, and the displacement changes of the monitoring points are recorded. If the displacement changes exceed the control value determined by the construction calculation, the passage is stopped and the preload of the lower alignment and back-top system is readjusted.

[0026] A temporary reinforcement structure for a crane using a post-cast strip includes an upper cross-belt load-sharing system, a lower alignment and back-top system, and a wheel track limiting channel;

[0027] The upper cross-strip load-sharing system is installed above the post-cast strip. The upper cross-strip load-sharing system includes a vehicular bridge deck, a longitudinal distribution beam, a first bearing pad beam, and a second bearing pad beam. The first bearing pad beam and the second bearing pad beam are respectively supported on the solid areas of the cast-in-place top slab on both sides of the post-cast strip. The longitudinal distribution beam is installed between the first bearing pad beam and the second bearing pad beam. The vehicular bridge deck is laid on top of the longitudinal distribution beam.

[0028] The lower alignment and jacking system is set below the cast-in-place top slabs on both sides of the post-cast strip. The lower alignment and jacking system includes a lower support beam, multiple adjustable supports and connecting rods. The lower support beam is set below the first pressure pad beam and the second pressure pad beam. The multiple adjustable supports are supported below the lower support beam. The connecting rods connect adjacent adjustable supports.

[0029] The adjustable support is provided with a preload adjustment part and a locking part. The preload adjustment part is used to make the lower support beam press against the bottom surface of the cast-in-place top plate on both sides of the post-cast strip. The locking part is used to lock the support height of the adjustable support after the lower support beam is pressed against the bottom surface of the cast-in-place strip.

[0030] The wheel track limiting channel is installed on the bridge deck and is located above the longitudinal distribution beam. It is used to limit the vehicle wheel track line from being above the longitudinal load distribution position of the upper crossbelt load distribution system.

[0031] In summary, the present invention has the following main beneficial effects:

[0032] This application achieves the effect of transferring vehicle wheel loads from the opening and edge of the post-cast strip to the solid areas of the already poured top slab on both sides by setting up an upper cross-slab load distribution system above the post-cast strip and forming a continuous force transmission path through the bridge deck, longitudinal distribution beams, first bearing pad beams, and second bearing pad beams. When a vehicle passes through the post-cast strip, the wheel load is first borne by the bridge deck and then diffused to both sides through the longitudinal distribution beams and bearing pad beams. This avoids the vehicle tires directly pressing on the weak parts of the concrete at the edge of the post-cast strip, reducing the risk of local pressure, deflection, and cracking at the slab edge, and making the temporary vehicle load path clearer during the unclosed stage of the post-cast strip.

[0033] This application establishes vertically aligned lower support systems below the first and second upper pressure zones, respectively. Before vehicle passage, the lower support beam and adjustable supports are pre-stressed, adjusted, and locked, thus enabling the lower supports to enter a stress-bearing state in advance. Compared to passively supporting only below the roof slab, this application aligns the main stress range of the lower support beam with the upper pressure zone, shortening the force transmission path of the vehicle load within the roof slab. Furthermore, pre-stressing eliminates the construction gap between the lower support beam and the bottom surface of the roof slab, reducing the impact contact and support stress lag issues during the first vehicle passage.

[0034] This application achieves a dual verification effect on vehicle wheel tracks and support deformation by setting wheel track limiting channels on the upper cross-belt load-sharing system and conducting trial traffic monitoring before official opening. The wheel track limiting channels ensure that the left and right wheel tracks of the vehicle are kept above the longitudinal load-sharing position, preventing the vehicle from being biased to the edge area of ​​the post-cast strip. Trial traffic monitoring can detect problems such as insufficient preload, component displacement, support settlement, or wheel track imbalance before official opening, and can be corrected by readjusting the lower alignment and backfilling system or adjusting the wheel track limiting channels, thereby improving the safety and controllability of the temporary reinforcement construction of the post-cast strip for vehicles. Attached Figure Description

[0035] Figure 1 This is a flowchart of the method of the present invention.

[0036] Figure 2 This is a schematic diagram of the overall layout of the temporary reinforcement structure for the post-cast strip of the present invention. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1

[0039] refer to Figure 1 A construction method for a temporary reinforcement structure for a vehicle traveling on a post-cast strip includes the following steps:

[0040] S1: Verify the concrete strength and surface condition of the poured top slabs on both sides of the post-pouring strip to ensure that the poured top slabs on both sides of the post-pouring strip meet the reinforcement construction conditions before temporary vehicle passage.

[0041] S2: Based on the structural drawings of the basement roof slab, the location of the post-cast strip, and the vehicle traffic route, determine the direction of travel, wheel track, and temporary reinforcement range for vehicles crossing the post-cast strip;

[0042] S3: Lay out lines on the cast-in-place slabs on both sides of the post-cast strip to form the first upper bearing area and the second upper bearing area, so that the first upper bearing area and the second upper bearing area are located on both sides of the post-cast strip, and both the first upper bearing area and the second upper bearing area are located within the solid area of ​​the cast-in-place slab.

[0043] S4: Determine a first lower support area and a second lower support area below the first upper pressure area and the second upper pressure area respectively, so that the first lower support area is located within the vertical projection range of the first upper pressure area, and the second lower support area is located within the vertical projection range of the second upper pressure area.

[0044] S5: Install the lower alignment and backing system in the first and second lower support areas respectively, and make the lower alignment and backing system press against the bottom surface of the cast-in-place top slab on both sides of the post-cast strip.

[0045] S6: Perform pre-compression adjustment on the lower alignment and back-top system, and lock the support height of the lower alignment and back-top system after the pre-compression adjustment is completed;

[0046] S7: Install an upper cross-belt load distribution system between the first upper pressure zone and the second upper pressure zone, so that the upper cross-belt load distribution system spans above the post-cast strip, and the vehicle wheel load is transferred to the first upper pressure zone and the second upper pressure zone through the upper cross-belt load distribution system.

[0047] S8: Set a wheel track limiting channel on the upper crossbelt load distribution system so that the vehicle wheel track line is located above the longitudinal load distribution position of the upper crossbelt load distribution system;

[0048] S9: Conduct trial passage and test the deformation status of the cast-in-place top slabs on both sides of the post-cast strip and the lower alignment back jacking system. When the detected deformation value does not exceed the control value determined by the construction calculation, limited vehicle passage is opened.

[0049] This application applies to situations where construction vehicles need to temporarily cross the post-cast strip when the post-cast strip of the basement roof slab, garage roof slab, or other floor slab structure has not yet been closed, or when the conditions for direct vehicle passage have not been met after the post-cast strip has been closed.

[0050] The construction method described in this application is not simply setting up ordinary back support on both sides of the post-cast strip, nor is it simply laying steel plates on top of the post-cast strip for vehicles to pass through. Instead, before the vehicle wheel load enters the post-cast strip area, the vehicle wheel load is first distributed to the solid areas of the already poured top slab on both sides of the post-cast strip through the upper cross-belt load distribution system. Then, the load is borne by the lower alignment back support system located within the corresponding vertical projection range. Combined with pre-stressing locking, wheel track limiting, and trial passage monitoring, the vehicle wheel load is transmitted according to the predetermined force transmission path.

[0051] In this embodiment, the poured roof slabs on both sides of the post-cast strip refer to the concrete roof slabs located on both sides of the post-cast strip that have been poured and meet the strength requirements for temporary vehicle passage. The edge of the post-cast strip refers to the junction between the reserved opening of the post-cast strip and the poured roof slabs on both sides of the post-cast strip. The solid area of ​​the poured roof slab refers to the solid area of ​​the roof slab on both sides of the post-cast strip that has been poured and can serve as a bearing surface. This area does not include the post-cast strip opening, the construction joint damage area, the area where the reserved reinforcement is concentrated and exposed, the corner chipping area of ​​the slab edge, the exposed reinforcement area, the loose concrete area, and the local defect area that is not suitable as a bearing surface after on-site inspection.

[0052] Before construction, the concrete strength and surface condition of the already poured slabs on both sides of the post-cast strip must be verified. Concrete strength can be determined through strength reports of test blocks cured under the same conditions, rebound test records, structural entity test records, or strength data approved by the construction unit. The surface condition mainly involves verifying for through cracks, obvious damage, honeycomb pitting, chipped corners, exposed reinforcement, localized hollow areas, or obvious unevenness affecting the stable support of the bearing pad beam. If the concrete strength of the already poured slabs on both sides of the post-cast strip does not meet the temporary vehicle passage strength requirements determined by construction calculations, or if the slab surface has obvious defects affecting load-bearing capacity, vehicles must not cross the post-cast strip.

[0053] The requirements for temporary vehicle traffic strength, vehicle speed, deformation control values, preload control values, and local bearing pressure control values ​​shall all be determined by a specific construction plan or temporary reinforcement calculation report. The specific construction plan or temporary reinforcement calculation report shall at least include the vehicle's total weight, axle load, wheelbase, tire contact area, post-cast strip width, top slab thickness, concrete strength grade, component specifications of the upper cross-span load-sharing system, support arrangement of the lower alignment and backfilling system, allowable bearing capacity of adjustable supports, and monitoring and control requirements. During on-site construction, if the vehicle type, total vehicle weight, driving direction, post-cast strip location, or reinforcement component specifications change, the temporary reinforcement range, bearing pad beam location, lower support beam location, and trial traffic control values ​​shall be recalculated.

[0054] After completing the strength and slab condition verification, based on the basement roof slab structural drawings, the location of the post-cast strip, and vehicle traffic routes, determine the vehicle's travel direction, wheel track lines, and temporary reinforcement area when crossing the post-cast strip. The preferred travel direction for vehicles crossing the post-cast strip is approximately perpendicular to the length of the strip, making it easier to control the stress process and passage time when the vehicle passes through the strip area. The wheel track lines are determined based on the actual wheelbase of the vehicle's left and right wheels, and can be determined using vehicle technical data, on-site layout, or test pressure imprints to establish the center lines of the left and right wheels on the roof slab.

[0055] When determining the scope of temporary reinforcement, the projection range of the vehicle's wheel track line along the length of the post-cast strip is used as the basis, extending outwards along both the vehicle entry and exit sides to form reinforcement extension sections. These extension sections cover the wheel load transition area before and after the vehicle's front or rear wheels approach the post-cast strip, preventing wheel loads from acting on the vicinity of the post-cast strip edge before the vehicle tires have fully entered the upper cross-belt load distribution system. The length of the reinforcement extension section is determined by the vehicle's wheelbase, tire contact length, vehicle speed, post-cast strip width, and specific construction calculations, rather than using fixed values ​​directly, to accommodate different vehicles and roof structures.

[0056] Subsequently, lines are laid out on the already poured slab on both sides of the post-cast strip to form the first and second upper bearing zones. The first and second upper bearing zones are located on both sides of the post-cast strip and within the solid area of ​​the already poured slab. The first and second upper bearing zones do not directly adhere to the edge of the post-cast strip, but rather maintain a clearance distance. This clearance distance is determined based on the integrity of the concrete at the edge of the post-cast strip, the extent of exposed reinforcing bars, the width of the slab edge notch, and the width of the bottom surface of the bearing pad beam. During construction layout, the side of the bearing pad beam facing the post-cast strip must not press on the edge of the post-cast strip opening, chipped corners, exposed reinforcing bars, or loose concrete areas. The bottom surface of the bearing pad beam should entirely fall within the continuous, flat, and undamaged area of ​​the already poured slab.

[0057] After the first and second upper bearing zones are laid out, the first and second bearing pad beams are laid in the first and second upper bearing zones respectively. The length of the first and second bearing pad beams is arranged along the length of the post-cast strip, and their bottom surfaces are completely supported on the already cast top slabs on both sides of the post-cast strip. "Complete support" here means that the main stress-bearing area of ​​the bearing pad beam's bottom surface is in continuous contact with the surface of the cast top slab, without any obvious suspension, warping, or localized suspension. If the slab surface is locally uneven, a leveling pad or anti-slip pad layer can be placed between the bearing pad beam and the top slab. The leveling pad is used to eliminate local height differences, and the anti-slip pad layer is used to reduce component slippage caused by vehicle starting, braking, or vibration.

[0058] The first and second bearing pad beams can be made of structural steel, composite steel beams, square steel pipe beams, or other rigid distribution components that meet the construction calculation requirements. Their function is not simply to level the surface, but to spread the wheel load transmitted from the longitudinal distribution beams along the length of the post-cast strip, reducing the local bearing pressure concentration on the already cast top slabs on both sides of the post-cast strip.

[0059] Below the first and second upper bearing zones, the first and second lower support zones are respectively determined. The first lower support zone is located within the vertical projection range of the first upper bearing zone, and the second lower support zone is located within the vertical projection range of the second upper bearing zone. During construction layout, the position of the upper bearing zone can be projected onto the base slab or lower structural space using a laser line projector, plumb bob, or total station, and the positions of the lower support beam and adjustable support components can then be determined accordingly. The vertical correspondence refers to the centerline or main stress area of ​​the lower support beam being located within the vertical projection range of the corresponding bearing pad beam. If the lower support beam cannot be completely located within this vertical projection range due to limitations imposed by basement beams, columns, walls, or equipment foundations, the support reaction force should be transferred back to the vertical projection range of the corresponding upper bearing zone through a transfer beam, ensuring that vehicle wheel loads are not primarily borne by the cantilever of the post-cast strip edge slab.

[0060] The lower alignment and jacking system is installed in the first and second lower support zones respectively. The lower alignment and jacking system includes a lower support beam, multiple adjustable supports, and connecting rods. During installation, the lower support beam is first positioned within the vertical projection range of the corresponding upper pressure zone, ensuring that the length direction of the lower support beam is consistent with or substantially consistent with the length direction of the corresponding pressure pad beam; then, multiple adjustable supports are placed under the lower support beam; subsequently, adjacent adjustable supports are connected via connecting rods, forming a stable overall support unit.

[0061] Adjustable supports can be constructed using disc-lock scaffold uprights with adjustable top supports, steel pipe columns with adjustable bases, or other vertical support components capable of adjusting the tightening height and meeting load-bearing requirements. The lower support beam can be a steel beam, square steel pipe beam, or composite steel beam, with its cross-sectional specifications determined by the specific construction plan or temporary reinforcement calculation. The lower end of the adjustable support should be supported on the basement floor slab, the lower floor slab, or other structural surface capable of withstanding the support reaction force. If necessary, a bottom pad should be installed at the lower end of the adjustable support to ensure stable transmission of the support reaction force.

[0062] The connecting rods include longitudinal connecting rods along the length of the post-cast strip and transverse connecting rods perpendicular to the length of the post-cast strip. The longitudinal connecting rods connect adjacent adjustable supports on the same side of the post-cast strip, limiting the relative displacement of these supports along the length of the post-cast strip. The transverse connecting rods connect adjacent adjustable supports on both sides of the post-cast strip, creating lateral constraints on the support systems of the first and second lower support zones. Through the cooperation of the longitudinal and transverse connecting rods, the lower alignment and backfilling system can resist local swaying and eccentric compression of the supports when vehicles pass, reducing sudden changes in force on individual supports.

[0063] After the lower alignment and jacking system is installed, it undergoes pre-stressing adjustment. Pre-stressing adjustment is not simply adjusting the jacks to contact the bottom surface of the roof slab; rather, it ensures that the lower support beam has established stable contact with the already poured roof slab surfaces on both sides of the post-cast strip before vehicle passage, and that the adjustable supports are brought into a stressed state in advance. Specifically, construction workers adjust multiple adjustable supports sequentially, gradually tightening the lower support beam against the bottom surface of the poured roof slab from the middle outwards. This gradual tightening method avoids the lower support beam being suspended in the middle due to tightening the ends first, and also reduces uneven stress on the roof slab surface caused by excessive local jacking.

[0064] The criteria for determining whether pre-stressing adjustment is complete are as follows: there is no visible gap between the lower support beam and the bottom surface of the poured roof slab; when checked with a feeler gauge, visual inspection, or monitoring instruments, the lower support beam forms continuous contact with the bottom surface of the roof slab along its length; all the top supports of multiple adjustable supports are under pressure; after the locking components are tightened, the adjustable supports do not show significant loosening during manual shaking inspection. For precise control, pressure sensors can be installed at the adjustable supports or the lower support beam, using the target pre-stress determined by the specific construction plan as the locking basis. Locking methods can include locking nuts, pin limiters, wedge clamps, or self-locking structures for the adjustable top supports, as long as the support height remains stable under vehicle traffic vibrations.

[0065] To provide a clear basis for preloading adjustment and on-site monitoring, the following engineering calculation relationships can be adopted in this embodiment. The following formulas are used to explain the determination methods of vehicle load, bearing stress, preloading state, and trial passage deformation in this embodiment. The specific control values ​​are determined by the special construction plan or temporary reinforcement calculation sheet in combination with the engineering structure and vehicle load.

[0066] The design load for a single wheel of a vehicle is based on:

[0067] ;

[0068] In the formula, For the first Design load of a single wheel corresponding to each axle; This is the power amplification factor for vehicle passage; For the first Axle load of each axle; For the first The number of load-bearing wheels corresponding to each axle; Number the axle. The dynamic coefficient is determined by the specific construction plan based on vehicle speed, bridge deck stiffness, and road surface smoothness. If the specific construction plan or existing construction calculation data already contains a dynamic coefficient, that coefficient is directly adopted. This formula is used to convert vehicle axle loads into single-wheel design loads entering the upper cross-belt load distribution system.

[0069] The average bearing stress transmitted from the bearing pad beam to the already poured top slab is verified as follows:

[0070] ;

[0071] In the formula, For the first The average bearing stress transmitted from the bearing pad beam to the already poured top slab; For the first The supporting reaction force corresponding to the bearing pad beam; For the first The effective bearing area between the bearing pad beam and the already poured top slab; Number the support position of the bearing pad beam. The stress distribution relationship is determined by the design load of a single wheel of the vehicle, the bridge deck, the longitudinal distribution beam, and the bearing pad beam. This excludes areas where the bottom of the bearing pad beam is suspended, not in contact with, damaged, or falls on a non-solid area. During construction, it should be ensured that... It shall not exceed the local bearing pressure control value of the roof slab determined by the special construction plan or temporary reinforcement calculation.

[0072] The target preload of the lower alignment and top-return system is as follows:

[0073] ;

[0074] In the formula, The target preload for a single adjustable support or a group of adjustable supports; This is the preload ratio coefficient; This refers to the design support reaction force corresponding to the adjustable support member or the group of adjustable supports under vehicle traffic conditions. The specific construction plan is determined based on the allowable bearing capacity of the adjustable supports, the local bearing pressure conditions of the top slab bottom surface, the stiffness of the lower support beam, and the on-site monitoring requirements. The preload must not exceed the allowable preload of the adjustable support, nor should it cause reverse jacking or new cracks in the already poured top slab. This formula is used to ensure that the lower alignment and backfilling system is in a stressed state before vehicles pass, avoiding impact contact when vehicles first pass.

[0075] The maximum displacement change during the trial passage is calculated according to:

[0076] ;

[0077] In the formula, This represents the maximum displacement change during the trial passage. For monitoring points during vehicle passage The displacement value at time; The initial displacement value of the same monitoring point before the vehicle passes; Monitoring times during the vehicle trial run; The total monitoring time for one trial passage process; Indicates in The maximum value is taken within the monitoring period.

[0078] when If the displacement does not exceed the displacement control value determined by the specific construction plan or temporary reinforcement calculation, the corresponding monitoring point is considered to meet the trial passage requirements; when any monitoring point When the corresponding displacement control value is exceeded, vehicle traffic is stopped, and the upper cross-belt load distribution system, lower alignment and back-top system, and preload locking status are re-checked.

[0079] After the lower alignment and backfilling system is preloaded and locked, the upper cross-belt load-sharing system is installed between the first and second upper bearing zones. The upper cross-belt load-sharing system includes the bridge deck, longitudinal distribution beams, first bearing pad beams, and second bearing pad beams. During installation, the first and second bearing pad beams are first installed in the first and second upper bearing zones respectively. Then, the longitudinal distribution beams are straddling between the first and second bearing pad beams, and finally, the bridge deck is laid on the longitudinal distribution beams.

[0080] The bridge deck covers the width of vehicle passage, with longitudinal distribution beams positioned along the vehicle travel direction, and first and second bearing pad beams positioned along the length of the post-cast strip. Vehicle wheel loads are first borne by the bridge deck, then transferred to the longitudinal distribution beams, subsequently to the bearing pad beams on both sides of the post-cast strip, and finally transmitted via the already cast top slabs on both sides of the post-cast strip to the lower alignment and backfilling system. Therefore, vehicle wheel loads do not directly act on the opening area of ​​the post-cast strip, nor do they primarily rely on the cantilevered bearing capacity of the post-cast strip edge slab.

[0081] The longitudinal load-sharing beams include a first longitudinal beam and a second longitudinal beam. The first and second longitudinal beams are respectively positioned below the wheel tracks on both sides of the vehicle, allowing the left and right wheel loads to be transferred to the first and second bearing pad beams, respectively. The longitudinal load-sharing position refers to the load-bearing zone formed by the first and second longitudinal beams below the bridge deck. The left and right wheel tracks of the vehicle should fall within their respective load-bearing zones; when there is a permissible deviation in the vehicle's wheel tracks during construction, the deviated wheel tracks should still be within the width coverage of the first or second longitudinal beam, or within the effective load-bearing range formed by the first and second longitudinal beams and the bridge deck above them.

[0082] The bridge deck and longitudinal distribution beam can be connected using clamping plates, bolts, clips, or welded retaining components. The connection method should be designed to prevent slippage of the bridge deck during vehicle braking and starting. The joints between bridge decks should preferably avoid vehicle wheel tracks. Overlapping clamping plates can be installed at the joints to reduce the impact when tires pass over them.

[0083] After the superstructure cross-belt load distribution system is installed, a wheel track limiting channel is installed on it. This channel can be formed by limiting beams located on both sides of the bridge deck, creating a passage for vehicles to pass through. This channel is located above the longitudinal load distribution position of the superstructure cross-belt load distribution system, specifically within the load-bearing range of the first and second longitudinal beams. The limiting beams can be made of structural steel, square steel tubing, precast concrete blocks, or detachable steel limiting seats, and are fixed to the bridge deck using bolts, pressure plates, or counterweights. The wheel track limiting channel does not function as a regular safety barrier; rather, it ensures that the vehicle's wheel load enters the preset force transmission path from the perspective of vehicle wheel track control, preventing the vehicle from biasing towards the edge area of ​​the post-cast strip.

[0084] After setting up the wheel track limiting channel, a trial run is conducted. Before the trial run, monitoring points are set up on the bottom surface of the cast-in-place slab on both sides of the post-cast strip, at the lower support beam, and at the adjustable support components. The monitoring points on the bottom surface of the slab are used to observe the deflection of the slab edges on both sides of the post-cast strip; the monitoring points on the lower support beam are used to observe the deflection changes of the support beam under stress; and the monitoring points on the adjustable support components are used to observe the settlement, displacement, and loosening of the support components. Monitoring can be performed using a level, theodolite, displacement gauge, dial gauge, plumb bob with a ruler, or other instruments capable of recording displacement changes. The monitoring data should at least record the initial value before vehicle passage, the change value when the front wheels of the vehicle enter, the change value when the vehicle body is above the post-cast strip, and the recovery value after the rear wheels of the vehicle leave.

[0085] During the trial run, vehicles will pass through the upper cross-belt load-sharing system at the speed determined by the specific construction plan or temporary reinforcement calculation. Construction personnel will simultaneously record the displacement changes at each monitoring point. If the displacement changes at each monitoring point do not exceed the control values ​​determined by the specific construction plan or temporary reinforcement calculation, and if the upper cross-belt load-sharing system does not exhibit slippage of the bridge deck, warping of the longitudinal distribution beam, displacement of the bearing pad beam, or loosening of the limiting retaining beam, and the lower alignment and jacking system does not exhibit settlement of adjustable support components, loosening of connecting rods, or significant deformation of the lower support beam, then the trial run is considered to meet the construction control requirements, and limited vehicle traffic can be opened.

[0086] The restricted vehicle passage means that only vehicles of the specified types, total weight, axle load, and wheelbase, as determined by the specific construction plan or temporary reinforcement calculations, are permitted to pass through the post-cast strip area along a designated route. Vehicles are restricted to low speed, single-vehicle operation, and center-of-way passage. Vehicles not included in the construction calculations are prohibited from directly using the temporary reinforcement structure. Multiple vehicles are not permitted to pass through or park in the same reinforcement area simultaneously, and vehicles are prohibited from abruptly stopping, turning sharply, or remaining stationary above the post-cast strip for extended periods.

[0087] If, during the trial run, the displacement change at any monitoring point exceeds the control value determined by the specific construction plan or temporary reinforcement calculation, or if there is loosening of components, localized abnormal noise, slippage of the bridge deck, settlement of adjustable supports, or separation of the lower support beam from the bottom surface of the roof slab, vehicle traffic must be stopped immediately. After stopping, first remove the upper vehicle load, then check the condition of the first bearing pad beam, the second bearing pad beam, the longitudinal distribution beam, the bridge deck, the lower support beam, the adjustable supports, and the connecting rods. If insufficient preload causes the lower support beam to not continuously contact the bottom surface of the roof slab, readjust the preload state of the lower alignment and jacking system; if the vehicle wheel track deviation causes uneven loading, adjust the wheel track limiting channel; if uneven bearing pad beam support causes localized stress concentration, re-level the bottom of the bearing pad beam. After adjustment, conduct another trial run until the construction control requirements are met.

[0088] The force transmission path in this embodiment is as follows: the vehicle wheel load is transferred to the bridge deck, which then transfers the load to the first and second longitudinal beams. These beams then transfer the load to the first and second bearing pad beams, which distribute the load to the solid areas of the cast-in-place slabs on both sides of the post-cast strip. Finally, the load is supported by the lower support beams and adjustable supports located within the corresponding vertical projection range. This force transmission path ensures that the vehicle load does not fall directly on the opening area of ​​the post-cast strip, nor does it primarily rely on the cantilever bearing capacity of the post-cast strip edge slab. Instead, it forms corresponding short force transmission paths through upper cross-slab load distribution and lower alignment and back-support.

[0089] This embodiment differs from the scheme that only sets ordinary support rods on both sides of the post-cast strip. The latter mainly forms vertical support on both sides of the post-cast strip, but the vehicle wheel load may still act on a local position of the top slab first, and then be passively transferred to the support components. In this embodiment, the wheel load is first distributed across the belt through the bridge deck, longitudinal distribution beam and bearing pad beam, and then the load is borne by the lower support beam and adjustable support components within the corresponding projection range, making the wheel load path clearer. Unlike the scheme that only sets ordinary back-top frames under the basement top slab, this embodiment requires that the first lower support area and the second lower support area be located within the vertical projection range of the first upper bearing area and the second upper bearing area, respectively, and the lower alignment back-top system is pre-loaded and locked before passage, thus reducing the stress lag caused by construction gaps between the support system and the bottom surface of the top slab. Unlike the scheme that simply lays steel plates or bridge decks, this embodiment also sets wheel track limiting channels and trial passage monitoring, which can restrict the vehicle wheel tracks above the longitudinal load distribution position, and verify the effectiveness of the force transmission system through monitoring results before formal passage.

[0090] In another embodiment, when there are beams, columns, walls, or equipment foundations below the cast-in-place slabs on both sides of the post-cast strip, the lower support beams can be arranged in segments to avoid obstacles. However, each segment of the lower support beam should still be located within the vertical projection range of the corresponding upper pressure zone and connected to adjacent supports via connecting rods or transfer beams. If there is an angle between the vehicle wheel track line and the length direction of the post-cast strip, the first longitudinal beam and the second longitudinal beam can be arranged along the actual travel direction of the vehicle. The first pressure pad beam and the second pressure pad beam are still arranged along or close to the length direction of the post-cast strip to ensure that the longitudinal distribution beams cross the post-cast strip and transfer the load to the cast-in-place slabs on both sides of the post-cast strip.

[0091] In another embodiment, if the construction site requires subsequent removal of the temporary reinforcement structure, it should be carried out after the post-cast strip is closed and the removal conditions determined by the specific construction plan or temporary reinforcement calculation report are met. During removal, first close the vehicle passageway, then remove the wheel track limiting channel and the bridge deck, followed by the longitudinal distribution beam, the first bearing pad beam, and the second bearing pad beam. Next, release the pre-stress lock of the lower alignment and jacking system, and finally remove the lower support beam, adjustable support components, and connecting rods. This sequence avoids prematurely removing the lower support before the upper vehicle passage components are removed, and also avoids the residual load of the upper components continuing to act on the top slabs on both sides of the post-cast strip after the lower support is removed.

[0092] Through the above construction method, this application can form a closed-loop construction system under post-cast strip traffic conditions, consisting of upper cross-strip load distribution, lower alignment and back-jacking, pre-stressing locking, wheel track limiting, and trial passage monitoring. Vehicle wheel loads are first diffused by the bridge deck and longitudinal distribution beams, then transferred to the solid area of ​​the already cast top slab via the bearing pads on both sides, and finally borne by the vertically corresponding lower alignment and back-jacking system, thereby reducing localized pressure on the edges of the post-cast strip and delayed stress on the supports. Pre-stressing locking ensures the lower alignment and back-jacking system is operational before vehicle passage, wheel track limiting keeps the vehicle wheel load within the design force transmission range, and trial passage monitoring is used to identify and correct insufficient pre-stressing, component displacement, or wheel track eccentricity before formal passage. The steps of this method are interconnected, and construction personnel can implement it based on structural drawings, vehicle data, specialized construction plans, and on-site monitoring results, without relying on undisclosed specialized equipment or unavailable data.

[0093] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A construction method for a temporary reinforcement structure for a post-cast strip trolley, characterized in that, Includes the following steps: S1: Verify the concrete strength and surface condition of the poured top slabs on both sides of the post-pouring strip to ensure that the poured top slabs on both sides of the post-pouring strip meet the reinforcement construction conditions before temporary vehicle passage. S2: Based on the structural drawings of the basement roof slab, the location of the post-cast strip, and the vehicle traffic route, determine the direction of travel, wheel track, and temporary reinforcement range for vehicles crossing the post-cast strip; S3: Lay out lines on the cast-in-place slabs on both sides of the post-cast strip to form the first upper bearing area and the second upper bearing area, so that the first upper bearing area and the second upper bearing area are located on both sides of the post-cast strip, and both the first upper bearing area and the second upper bearing area are located within the solid area of ​​the cast-in-place slab. S4: Determine a first lower support area and a second lower support area below the first upper pressure area and the second upper pressure area respectively, so that the first lower support area is located within the vertical projection range of the first upper pressure area, and the second lower support area is located within the vertical projection range of the second upper pressure area. S5: Install the lower alignment and backing system in the first and second lower support areas respectively, and make the lower alignment and backing system press against the bottom surface of the cast-in-place top slab on both sides of the post-cast strip. S6: Perform pre-compression adjustment on the lower alignment and back-top system, and lock the support height of the lower alignment and back-top system after the pre-compression adjustment is completed; S7: Install an upper cross-belt load distribution system between the first upper pressure zone and the second upper pressure zone, so that the upper cross-belt load distribution system spans above the post-cast strip, and the vehicle wheel load is transferred to the first upper pressure zone and the second upper pressure zone through the upper cross-belt load distribution system. S8: Set a wheel track limiting channel on the upper crossbelt load distribution system so that the vehicle wheel track line is located above the longitudinal load distribution position of the upper crossbelt load distribution system; S9: Conduct trial passage and test the deformation status of the cast-in-place top slabs on both sides of the post-cast strip and the lower alignment back jacking system. When the detected deformation value does not exceed the control value determined by the construction calculation, limited vehicle passage is opened.

2. The construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 1, characterized in that, When determining the scope of temporary reinforcement, the projection range of the vehicle wheel track line in the length direction of the post-cast strip is used as the basis, and reinforcement extension sections are formed by extending outward along the vehicle entry side and the vehicle exit side respectively. The reinforcement extension sections are used to cover the wheel load transition area before and after the front or rear wheels of the vehicle approach the post-cast strip.

3. A construction method for a temporary reinforcement structure for a post-cast strip traveling vehicle according to claim 2, characterized in that, After the first and second upper pressure zones are laid out, pressure bearing beams are laid in the first and second upper pressure zones respectively. The length of the pressure bearing beams is arranged along the length of the post-cast strip, and the bottom surface of the pressure bearing beams is completely supported on the cast-in-place top slabs on both sides of the post-cast strip.

4. A construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 3, characterized in that, The lower alignment and jacking system includes a lower support beam, multiple adjustable supports, and connecting rods. When installing the lower alignment and jacking system, the lower support beam is first placed within the vertical projection range of the corresponding upper pressure zone, and then multiple adjustable supports are supported below the lower support beam. Subsequently, adjacent adjustable supports are connected by connecting rods.

5. A construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 4, characterized in that, When pre-stressing the lower alignment and jacking system, adjust multiple adjustable supports in sequence so that the lower support beam gradually presses against the bottom surface of the poured slab from the middle to both ends. After the lower support beam and the bottom surface of the poured slab form a continuous contact, lock the support height of the multiple adjustable supports.

6. A construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 5, characterized in that, The connecting rod includes a longitudinal connecting rod arranged along the length direction of the post-pouring strip and a transverse connecting rod arranged perpendicular to the length direction of the post-pouring strip. The longitudinal connecting rod connects adjacent adjustable support members located on the same side of the post-pouring strip, and the transverse connecting rod connects adjacent adjustable support members located on both sides of the post-pouring strip.

7. A construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 6, characterized in that, The upper cross-belt load distribution system includes a bridge deck, a longitudinal distribution beam, a first bearing pad beam, and a second bearing pad beam. When installing the upper cross-belt load distribution system, the first bearing pad beam and the second bearing pad beam are first installed in the first upper bearing area and the second upper bearing area, respectively. Then, the longitudinal distribution beam is straddled between the first bearing pad beam and the second bearing pad beam. Finally, the bridge deck is laid on the longitudinal distribution beam.

8. A construction method for a temporary reinforcement structure for a post-cast strip crane according to claim 7, characterized in that, The longitudinal distribution beam includes a first longitudinal beam and a second longitudinal beam. The first longitudinal beam and the second longitudinal beam are respectively arranged below the wheel tracks on both sides of the vehicle, so that the left and right wheel loads of the vehicle are transferred to the first bearing pad beam and the second bearing pad beam through the first longitudinal beam and the second longitudinal beam, respectively.

9. A construction method for a temporary reinforcement structure for a post-cast strip traveling vehicle according to claim 8, characterized in that, When setting up a wheel track limiting channel, limit beams are installed on both sides of the upper crossbelt load distribution system, and a channel for vehicles to pass through is formed between the two limit beams. The channel is located above the longitudinal load distribution position of the upper crossbelt load distribution system. During the trial run, monitoring points are set up on the bottom surface of the cast-in-place top slab on both sides of the post-cast strip, at the lower support beam and adjustable support components. Vehicles pass through the upper cross-strip load-sharing system at the speed determined by the construction calculation, and the displacement changes of the monitoring points are recorded. If the displacement changes exceed the control value determined by the construction calculation, the passage is stopped and the preload of the lower alignment and back-top system is readjusted.

10. A temporary reinforcement structure for a crane traveling along a post-cast strip, applicable to the construction method of the temporary reinforcement structure for a crane traveling along a post-cast strip as described in any one of claims 1-9, characterized in that, This includes an upper cross-belt load distribution system, a lower alignment and return system, and wheel track limiting channels; The upper cross-strip load-sharing system is installed above the post-cast strip. The upper cross-strip load-sharing system includes a vehicular bridge deck, a longitudinal distribution beam, a first bearing pad beam, and a second bearing pad beam. The first bearing pad beam and the second bearing pad beam are respectively supported on the solid areas of the cast-in-place top slab on both sides of the post-cast strip. The longitudinal distribution beam is installed between the first bearing pad beam and the second bearing pad beam. The vehicular bridge deck is laid on top of the longitudinal distribution beam. The lower alignment and jacking system is set below the cast-in-place top slabs on both sides of the post-cast strip. The lower alignment and jacking system includes a lower support beam, multiple adjustable supports and connecting rods. The lower support beam is set below the first pressure pad beam and the second pressure pad beam. The multiple adjustable supports are supported below the lower support beam. The connecting rods connect adjacent adjustable supports. The adjustable support is provided with a preload adjustment part and a locking part. The preload adjustment part is used to make the lower support beam press against the bottom surface of the cast-in-place top plate on both sides of the post-cast strip. The locking part is used to lock the support height of the adjustable support after the lower support beam is pressed against the bottom surface of the cast-in-place strip. The wheel track limiting channel is installed on the bridge deck and is located above the longitudinal distribution beam. It is used to limit the vehicle wheel track line from being above the longitudinal load distribution position of the upper cross-belt load distribution system.

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