Inhaul cable curtain wall construction method

Abstract

The invention relates to an inhaul cable curtain wall construction method. The inhaul cable curtain wall construction method comprises the following steps that a temporary load is added to the top of a curtain wall; a plurality of inhaul cables are arranged on the curtain wall, and the arrangement positions and the tensioning sequence of the inhaul cables are determined according to construction requirements; an inhaul cable tensioning machine is provided, and the inhaul cable is tensioned through the inhaul cable tensioning machine until the inhaul cable is tensioned to the tension required by the design; and after tensioning of the inhaul cables is completed, backfilling construction is conducted on the top of the curtain wall, the temporary loads at the corresponding positions are gradually removed till construction of the top of the curtain wall is completed, operation is convenient, and construction is easy.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, in particular to a cable curtain wall construction method. Background Art

[0002] Cable curtain walls are used in many large public buildings because of their good permeability and wide field of vision. The initial pre-tension of the cable in the cable net structure has a great influence on the stiffness of the structure. As the cable net deforms under wind loads and other factors, the stiffness of the cable net will change accordingly. The influence of pre-tension, geometric nonlinearity and boundary conditions needs to be considered in the calculation. The entire cable net structure must also establish sufficient pre-tension in the cables to meet the needs of bearing and deformation. As the cable force is tensioned, the structure will produce a certain deformation, and the deformation of the structure will affect the tensioned cables. Therefore, repeated adjustment of the tensioning cable force will inevitably seriously affect the construction period. Under the condition of tight construction period, special-shaped cable curtain walls are difficult to construct safely and quickly. During the construction stage of the cable curtain wall, the interior decoration of the cantilevered structure has not started. After the construction of the cable curtain wall is completed, the interior decoration project will be constructed. Due to the increase in permanent load, the cable force will be greatly lost. The sudden change of the cable force will further affect the safety of the cable structure and the sealing of the glass curtain wall. During each stage of prestressing of the curtain wall cable structure, the structure undergoes an adaptive process. The structure will redistribute the internal force through self-balancing, and its shape will change accordingly. Therefore, it is also a difficult problem to ensure that the state of the structure is consistent with the original design when tensioning is completed. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a cable curtain wall construction method, which sets a temporary load on the top of the curtain wall to ensure that the cables are consistent with the original design after tensioning, speed up the construction progress, save a lot of equipment and manpower, and reduce the construction period cost.

[0004] The technical solution to achieve the above purpose is a cable curtain wall construction method, comprising the following steps:

[0005] Add temporary loads to the top of the curtain wall;

[0006] Arrange a plurality of cables on the curtain wall, and determine the installation positions and tensioning sequence of the cables according to construction requirements;

[0007] Providing a cable tensioning machine, and tensioning the cable by the cable tensioning machine until the cable is tensioned to a tension required by design;

[0008] After the tensioning of the cables is completed, backfill construction is carried out on the top of the curtain wall and the temporary loads at the corresponding positions are gradually removed until the construction of the top of the curtain wall is completed.

[0009] Furthermore, after tensioning, the tension Fi of the cable is:

[0010] Fi = F0 + Fi loss;

[0011] Wherein F0 is the designed prestress of the cable, and Fi loss is the internal stress lost by the cable with the corresponding number after tensioning.

[0012] Furthermore, the Fi loss is calculated according to the following formula:

[0013]

[0014] Where Δi is the deformation of the cable, Li is the length of the cable, E is the elastic modulus, and A is the cross-sectional area of ​​the cable.

[0015] Furthermore, when installing the curtain wall, a total station is provided, and positioning and measuring of the curtain wall are performed by the total station.

[0016] Furthermore, when installing the curtain wall, the construction process is simulated by using MIDASGEN software.

[0017] Furthermore, when the cables are arranged, each cable is numbered.

[0018] Furthermore, during the backfill construction of the curtain wall, the cables are tested, and if the internal stress of the cables is lost, the cables are tensioned again.

[0019] Furthermore, when a temporary load is added, a water tank is provided and arranged on the top of the curtain wall, and when the curtain wall is backfilled, the water in the water tank is gradually discharged.

[0020] Furthermore, before the cables are arranged on the curtain wall, various structures of the curtain wall are checked, and if the design of the curtain wall does not meet the design specifications, the curtain wall is adjusted.

[0021] Furthermore, when the cable is set, a reflective sheet is set at a fixed position of the cable, and the initial coordinates are recorded. After the cable is tensioned, measurement and calibration are performed using the reflective sheet.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] By setting a temporary load on the top of the curtain wall to ensure that the cables are consistent with the original design after tensioning, the construction progress can be accelerated, a large amount of equipment and manpower can be saved, and the construction period cost can be reduced. The total station is used to monitor the deformation of the structure to ensure that the deformation during the tensioning process is controllable and reasonable, so as to ensure the safety of the structure during the construction period and ensure that the initial state of the structure after tensioning is consistent with the original design. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a cable curtain wall construction method;

[0025] Figure 2 A schematic diagram of a water tank counterweight scheme for a cable curtain wall construction method;

[0026] Legend: 1. Curtain wall; 2. Cable; 3. Water tank. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0028] See also Figure 1 A cable curtain wall construction method comprises the following steps: adding a temporary load to the top of the curtain wall 1; setting a plurality of cables 2 on the curtain wall 1, and determining the setting positions and tensioning sequence of the cables 2 according to construction requirements; providing a cable 2 tensioning machine, and tensioning the cables 2 by the cable 2 tensioning machine until the cables 2 are tensioned to the tension required by the design; after the tensioning of the cables 2 is completed, backfilling construction is performed on the top of the curtain wall 1 and the temporary loads at the corresponding positions are gradually removed until the construction of the top of the curtain wall 1 is completed.

[0029] In the present invention, a preferred implementation mode is as follows: during the construction of the curtain wall 1, an equal amount of load substitution is performed in the unconstructed area of ​​the curtain wall 1, and a temporary load is set on the top of the curtain wall 1 to avoid changes in the prestress of the cable 2 due to the difference in gravity before and after the construction of the curtain wall 1, which makes the cable 2 easy to crack, and analyzes the influence of the load of each floor on the cable 2 to avoid excessive loss of the prestress of the cable 2 and deformation of the curtain wall 1, and determines the prestress required for each cable 2, and provides a cable 2 tensioning machine to tension each cable 2, determines the base point of the curtain wall 1, and measures and lays out the curtain wall 1 and installs a connecting support on the curtain wall 1. Preferably, an ear plate can be set on the curtain wall 1, and the ear plate is used to connect the cable 2. During the construction process, various dimensions on site are monitored and re-measured. After the cable 2 is connected, backfill construction is performed on the curtain wall 1, and the temporary load at the corresponding position is removed.

[0030] Furthermore, after tensioning, the tension Fi of the cable 2 is:

[0031] Fi = F0 + Fi loss;

[0032] Wherein F0 is the designed prestress of the cable 2, and Fi loss is the internal stress lost by the cable 2 with the corresponding number after being tensioned.

[0033] Furthermore, the Fi loss is calculated according to the following formula:

[0034]

[0035] Where Δi is the deformation of cable 2, Li is the length of cable 2, E is the elastic modulus, and A is the cross-sectional area of ​​cable 2. Preferably, the calculation can be performed by using the reverse disassembly method, which is exactly the opposite of the actual construction sequence. First, the program is adjusted to the desired final state, and then reverse disassembly (gradually loosening the cable) is performed to obtain the calculation results of each stage in the construction process that we expect.

[0036] Furthermore, when installing the curtain wall 1 , a total station is provided, and positioning and measuring of the curtain wall 1 are performed by the total station.

[0037] Furthermore, when installing the curtain wall 1, the construction process is simulated by using MIDASGEN software.

[0038] Furthermore, when the cables 2 are arranged, each cable 2 is numbered.

[0039] Furthermore, during the backfill construction of the curtain wall 1, the cables 2 are tested, and if the internal stress of the cables 2 is lost, the cables 2 are tensioned again.

[0040] Furthermore, when a temporary load is added, a water tank 3 is provided, and the water tank 3 is set on the top of the curtain wall 1. When the curtain wall 1 is backfilled, the water in the water tank 3 is gradually discharged. Preferably, a 6-ton cylindrical plastic water tank 3 can be used as a counterweight, and when other parts are constructed later, the water is gradually released as the constant load is gradually in place.

[0041] Furthermore, before the cables 2 are arranged on the curtain wall 1 , various structures of the curtain wall 1 are checked. If the design of the curtain wall 1 does not meet the design specifications, the curtain wall 1 is adjusted.

[0042] Furthermore, when setting the cable 2, a reflective sheet is set at a fixed position of the cable 2, and the initial coordinates are recorded. After the cable 2 is tensioned, the reflective sheet is used for measurement and calibration. Preferably, the tensioning of the prestressed steel cable is double-controlled, that is, the tension of the prestressed steel cable is the main control. Before the cable is installed, reflective sheets are first affixed to all ear plates, and the initial coordinates are recorded, supplemented by monitoring the deformation of the structure. After each prestressed steel cable is tensioned, it should be measured and calibrated immediately. If an abnormality is found, the tensioning should be suspended, and the tensioning can be continued after the cause is found and measures are taken.

[0043] The following is an explanation of the use process of a cable curtain wall construction method of the present invention.

[0044] In the unconstructed area, the load is replaced by equal value. According to the design documents, the influence of the live load of each floor on Cable 2 has been considered and does not need to be calculated. During construction, only the dead load that is not in place needs to be considered. The concrete and partition walls of the third floor slab have been constructed, but the 150-thick surface layer and ceiling have not been built, and the total dead load of 3.5kN / m2 is not in place. Under the action of the dead load of 3.5kN / m2, the maximum deformation of the lower chord of Cable 2 is about 5.4mm. According to the design requirements, the live load of the third-floor exhibition hall and the roof is 5kN / m2. Under the action of the live load, the maximum deformation of the lower chord of Cable 2 is about 10.5mm. Due to the large deflection of Cable 2, in order to avoid cable force loss, a linear load counterweight is added to the range of Cable 2 in the third-floor exhibition hall to simulate the dead load and live load that are not in place.

[0045] The influence of the load on each floor on Cable 2 was analyzed. The actual construction situation on site was analyzed. The thickness of the building surface in the three-story exhibition hall reached 150mm, and there was also a ceiling load of 0.5kN / m2. After calculation, under these loads, the maximum deflection of the lower chord of Cable 2 was about 5.4mm. Although the deflection value was not large, the length of Cable 2 in the mid-span was short, only about 12.6 meters. According to Hooke's law, when the elongation of Cable 2 was reduced by 5.4mm, the pre-tension in the cable would be reduced by about 43kN, which was close to one-third of the designed pre-tension.

[0046] All cables 2 are numbered and calculated using the reverse disassembly method, which is exactly the opposite of the actual construction sequence. First, the program is used to adjust to the desired final state, and then reverse disassembly (gradually loosen the cables) is performed to obtain the desired calculation results for each stage of the construction process.

[0047] The construction process is simulated by MIDASGEN software. In order to achieve effective control of the tensioning process and calculate the changes in the internal force of the cable during the adjustment process, the MIDAS GEN software is used to simulate and analyze the entire tensioning process of the cable net based on the finite element model;

[0048] According to the design requirements, the design pre-tension of all vertical cables 2 is 150KN, and the design pre-tension of all horizontal cables 2 is 80kN (at 14℃). Cables 2 and curtain wall 1 columns on both sides have large deflections under the action of cable tension. Post-tensioned cables 2 will cause the internal force of the previously tensioned cables to be lost or even relaxed. The reduction of the pre-tension of cable 2 will directly reduce the stiffness of cable 2 and increase the mid-span deformation of cable 2. Therefore, during the construction process, the internal force of cable 2 should be strictly controlled to meet the design requirements.

[0049] During construction, tension control is adopted on site. During the tensioning process, the controlled tension of the cable 2 should be greater than the designed pre-tension to varying degrees. After all cables 2 are tensioned, the internal force of each cable should be reduced to the designed pre-tension.

[0050] In the present invention, a preferred embodiment is: all cables are numbered, the vertical cables are S01 to S25 from west to east, the horizontal cables are H01 to H07 from top to bottom, the horizontal cables on the west side of the gate are H08 to H10 from top to bottom, and the horizontal cables on the east side are H11 to H13.

[0051] Since the upper end of the vertical cable is fixed to the lower chord of the steel truss, during the tensioning process, the truss produces downward deflection under the action of the cable force, resulting in cable force loss. In order to meet the design requirements, the tensioning force of the cable should be appropriately amplified;

[0052] The tensioning sequence of the cables is: vertical cables first, then transverse cables; mid-span first, then both ends;

[0053] The initial state of cable 2 is: the tension of each vertical cable is 150kN, and the structure is deformed under the action of cable pre-tension. The process of determining the control cable force of each cable is as follows: when the S13 cable is tensioned, its initial state is that under the action of all cable forces, the structure is deformed to 9.894mm at the S13 node. If only 150kN tension is applied at S13, the deformation at S13 is 0.939mm.

[0054] After S13 is tensioned, the deformation of the truss at S13 is Δ 13后续 =9.894-0.939=8.955mm. During the entire tensioning process, the cable satisfies Hooke's law. Therefore, during the subsequent tensioning of the 24 cables, the S13 cable force loss can be calculated as follows:

[0055]

[0056] i——Call number

[0057] L——cable length (the cable expansion amount is much smaller than the original length of the cable, so it can be approximately considered that the cable length remains unchanged)

[0058] E——elastic modulus

[0059] A – cross-sectional area of ​​the cable.

[0060] Available, F 13后续损失 =70.48kN, so the control cable force when S13 is tensioned is 150+70.48=220.48kN

[0061] Continue to tension the S12 and S14 cables in sequence. The initial state is that under the action of all cable forces, the deformation of the structure at the S12 and S14 nodes is 9.516 and 9.856 mm respectively. If 150 kN tension is applied only at S12, S13, and S14 (S13 has been tensioned at this time), the deformation at S12 and S14 is 2.158 and 2.613 mm respectively.

[0062] After S12 and S14 are tensioned, the deformation of the truss at S12 is Δ 12后续 =9.516-2.158=7.358mm, Δ 14后续 =9.856-2.613=7.243mm. During the whole tensioning process, cable 2 still satisfies Hooke's law. Therefore, in the subsequent tensioning process of 22 cables, the force loss of S12 and S14 can still be calculated according to Hooke's law, and F 12后续损失 =58.09kN, F 14后续损失 =56.85kN, so during tensioning, the cable force controlled by S12 is 150+58.09=208.09kN, and the cable force controlled by S14 is 150+56.85=206.85kN

[0063] Continue tensioning, the calculation results of each vertical cable are as follows (mm, kN):

[0064] Statistical standard for deformation and internal force control of vertical cables in batches

[0065]

[0066]

[0067] The same is true for transverse cables. The deformation value is the sum of the deformations at the east and west ends of the cable. The calculation statistics are as follows (mm, kN):

[0068] Deformation of transverse cables in batches and statistics of controlled internal forces

[0069]

[0070] According to the tensioning sequence, the maximum control internal force of the vertical cable 2 during construction occurs at S13, with a maximum value of 220.48 kN, and the maximum control internal force of the transverse cable 2 is H05, with a maximum value of 93.25 kN. The cable that is first tensioned in the mid-span bears a larger tension, and the tensioning sequence can be appropriately optimized to reduce the control cable force during construction.

[0071] For the vertical cables, tensioning can be started from the two "shoulders" of the door head steel frame, roughly corresponding to the two trisection points of the cable 2, first to the middle, then to the two ends; for the horizontal cables, it can also be started from the two trisection points of the curtain wall 1 column, also first to the middle, then to the two ends. The specific tensioning sequence is shown in the table:

[0072] The secondary steel structure is deepened to check whether the position and elevation difference of anchor piers, embedded parts, and steel beam support surfaces meet the design and specification requirements. If not, timely adjustments should be made and corresponding remedies should be made. The strength and stability of components that are easily deformed, such as steel beams and anchor piers, should be re-tested. If the strength or stability is insufficient through calculation, reinforcement measures should be taken to ensure that the rigging installation tensioning has sufficient strength and a stable foundation. When installing the cable net system, the accurate position of the secondary steel structure, such as anchor piers and cable 2 ear plates, should be ensured, and the allowable deviation should not exceed ±1mm.

[0073] The load counterweight can be placed using a 6-ton cylindrical plastic water tank 3 as the counterweight. When other parts are constructed later, the water will be gradually released as the constant load is gradually in place.

[0074] Determine the base point, measure and lay out the lines, connect the supports and install them; establish a measurement control network according to the installation process and quality requirements of the cable 2 glass curtain wall 1, check the deviation of the construction size of the civil structure, determine whether the design value of the curtain wall 1 needs to be adjusted according to the deviation, and measure and lay out the external control line of the curtain wall 1 construction according to the design value of the curtain wall 1. Take the control line as the benchmark, and lay out the internal control line according to the requirements of the design drawings and the curtain wall 1 scheme construction drawings. Check whether the anchor position of the vertical cable 2 meets the design requirements. If the deviation is large, it should be adjusted or placed and embedded. After the initial tensioning of the cable 2 is completed, arrange the horizontal and vertical wire control network, and set a fulcrum for the horizontal wire in the middle of the span (spacing about 20 meters) to prevent the wire position from shifting.

[0075] The establishment of the measurement control network can be carried out by the internal control method. The control line of the building floor is measured by using a laser plumb line from the control line point on the first floor to the inside of the floor. The horizontal elevation of curtain wall 1 and the grid lines of curtain wall 1 are measured from the first floor using a level, theodolite, electronic total station and a 50m steel tape measure to the grids of each floor. The elevation of curtain wall 1, axis, control network and grid lines of cable structure installation are checked and re-measured using the external control line method using a theodolite and electronic total station.

[0076] The upper end of the vertical cable is connected to the steel beam connecting plate through the ear plate, and the lower end of the vertical cable is connected to the plate embedded part through the anchor bolt. The two ends of the horizontal cable are connected to the triangular steel frame at the corner position through the base. For the stability and safety of the entire curtain wall 1 system, the quality of the weld must be strictly guaranteed. All welds are welded with carbon dioxide shielded welding, and senior welders are selected to operate. After welding, all welds are subjected to radiographic inspection to ensure that the welding quality meets the specification requirements.

[0077] The construction monitoring site was re-measured using a precision positioning instrument called a "total station" to reposition and measure all the steel structures for the on-site glass and aluminum panel installation. The measured dimensions were then input into the computer glass cutting model diagram for comparison. Glass with no deviation or with a deviation of less than 3 mm would be fine-tuned during the actual installation process on site. Glass with a size deviation greater than 3 mm would be re-calibrated by on-site technicians and on-site surveyors, and the processing details that had been sent to the glass processing manufacturer would be immediately changed and adjusted to ensure ultra-high quality at the construction site.

[0078] Installation of cable 2, cable 2 curtain wall 1 The installation order of cable 2 is: first install the vertical cable 2, then install the horizontal cable 2. The installation method of vertical cable 2 is: first install the top connection end of each cable 2 and then install the bottom connection end. When installing cable 2, place the cable tray at the vertical position corresponding to each vertical cable, cable 2 corresponds to the upper steel beam, fix the winch clamp, tie the top connection end of cable 2 with a wire rope, and use the winch to lift cable 2, that is, install cable 2 and release it at the same time. When the fixed end rises to about 1.5m away from the ear plate, use two 2t guide chains to fix the top connection end to the corresponding ear plate through the pin shaft, and then fix the bottom connection end to the corresponding ear plate through the pin shaft. Other vertical cables are installed in this way.

[0079] The installation of transverse cables is divided into separate installation of transverse cables and overall installation of transverse cable trusses.

[0080] The installation method of the transverse cable 2 is as follows: each cable 2 is installed from top to bottom in sequence, and each cable 2 is installed with the fixed end first and then the adjustable end. During installation, place the cable tray below the fixed end, tie the fixed end of the cable 2 with a wire rope, and use a winch to lift the cable 2, that is, the cable 2 is installed and released at the same time. The fixed end is about 1.5m away from the ear plate, and two 2t guide chains are used to fix the fixed end to the corresponding ear plate through a pin shaft; tie the adjustable end of the cable 2 with a wire rope, and lift the adjustable end to the corresponding ear plate with the help of a winch, about 1.5m away from the ear plate, and use two 3t guide chains to fix the adjustable end to the corresponding ear plate through a pin shaft. Other transverse cables are installed in sequence according to this method. During the installation process, the position of the cable tray should be continuously adjusted according to the actual situation on site (gradually moving from the fixed end to the adjustable end) to ensure that the cable body of the cable 2 can be released smoothly.

[0081] Tensioning tooling design Tensioning tooling refers to some tensioning machines and equipment used in prestressed construction. The tensioning equipment uses tooling made of corresponding jacks and matching oil pumps. The jacks and oil pumps are calibrated according to the actual tensioning force required by the design and prestressing process, and a calibration certificate is produced to facilitate inspection and use. Prestressed steel cable tensioning adopts double control, that is, the tension of the prestressed steel cable is the main one. Before the cable is installed, reflective sheets are first affixed to all ear plates to record the initial coordinates and monitor the deformation of the structure as a supplement. After each prestressed steel cable is tensioned, it should be measured and proofread immediately. If an abnormality is found, the tensioning should be suspended until the cause is found and measures are taken before continuing the tensioning. Since there are many tensioning equipment components in this project, they must be carefully placed during installation so that the centroid of the tensioning equipment coincides with the steel cable to ensure that the prestressed steel cable does not produce eccentricity during tensioning; after the oil pump starts and the oil supply is normal, pressurization begins. When the graded tensioning reaches the controlled internal force value of the steel cable, the tensioning of the prestressed steel cable is completed. During tensioning, the oil supply speed must be controlled and the oil supply time should not be less than 0.5 minutes.

[0082] The cable in the prestressed cable structure has a thin cross section, low thermal inertia, and is more sensitive to changes in ambient temperature. Moreover, the cable 2 is behind the glass and is easily exposed to the sun. It absorbs solar energy and causes the temperature to rise, which reduces the prestress in the cable. Therefore, the temperature effect should be considered in conjunction with the setting of the prestress value. When the construction environment temperature is higher than the calculation reference temperature, the actual construction prestress value needs to be subtracted from the change in prestress with temperature; when the construction environment temperature is lower than the calculation reference temperature, the actual construction prestress value needs to be added to the change in prestress with temperature.

[0083] The calculation of this project takes into account ±22℃, the basic annual temperature difference is -8℃--36℃, and the reference temperature is 14℃.

[0084] During the construction and use period, the internal force or structural deformation of cable 2 needs to be tested regularly to understand the safety performance of the structure and ensure the safe use of the structure in the future. When the cable force loss detected is large, cable 2 needs to be re-tensioned to compensate for the cable force loss caused by gradual relaxation and other reasons.

[0085] The tensioning of the cable 2 needs to be done with the help of tensioning tools. Therefore, sufficient horizontal and vertical space should be reserved for the adjustment end of the cable 2 during design to ensure the installation and use of the tensioning tools. The tensioning end ear plate is inside the building surface layer, and the reserved decorative plate at the adjustment end should be removed if necessary.

[0086] Installation of glass panels

[0087] The quality of glass installation is directly related to the appearance of the curtain wall 1 after completion. Therefore, glass installation is also the most important step in the construction process of the point-connected glass curtain wall 1. The scaffolding needs to be checked again to see if it is stable and reliable.

[0088] After the steel cables are adjusted and tested, the glass installation can begin. Glass installation is a very precise job. If the structural dimension deviation is too large, it will bring difficulties to the glass installation. Before installing the glass, it is necessary to check and calibrate whether the verticality of the steel structure and the elevation of the connecting parts meet the requirements of the drawings.

[0089] 1. Glass installation

[0090] ① Check the size of the glass before unpacking. Glass with broken edges, cracks, obvious scratches, etc. is not allowed to be installed.

[0091] ②Clean the dust on the glass and the suction cup to ensure that the suction cup has sufficient suction force. The number of suction cups is determined according to the weight of the glass. It is strictly forbidden to use suction cups with insufficient suction force.

[0092] ③ Place neoprene pads in the bottom steel groove (two for each piece of glass, corresponding to 1 / 4 of the glass width from the edge).

[0093] ④ When lifting the glass, the glass should be delivered to the installation location at a uniform speed. When the glass is in place, the personnel on the scaffolding should use the single-claw glass suction cup as soon as possible to control and stabilize the glass to avoid collision and accidents.

[0094] ⑤After the glass stabilizes, people above and below should pay attention to protecting the glass.

[0095] When there is a groove on the upper part, let the upper part enter the groove first; when there is a groove on the lower part, the glass should be slowly placed into the groove, and then the glass should be fixed with a foam filling rod to prevent the glass from swinging in the groove and causing accidental breakage.

[0096] ⑥ After all adjustments are completed, the overall facade flatness should be checked. Only after confirmation can gluing be carried out.

[0097] 2. Error control

[0098] After each layer of glass is installed, the panels should be adjusted. The standard for glass adjustment is "horizontal, vertical, and flat", that is, the horizontal glue seam should be horizontal, the vertical glue seam should be vertical, and each glass should be on the same plane. In addition, the size of the glue seams should be checked to see if they are consistent. If not, adjustments should be made. After the glass panel adjustment is completed, the sealing pads around the installation fixture should be fixed immediately. After each layer of glass is adjusted, the error is controlled within ±3mm, and it is not accumulated in each layer to be controlled, distributed, and digested.

[0099] 3. Caulking and glue injection

[0100] (1) Before gluing, clean the glass and steel trough parts that need gluing with xylene. Use a foam stick to fill the gap between the glass and the steel trough, pay attention to straightness, and leave a net height of 6mm for gluing. Masking tape should be pasted on all parts that need gluing, and pay attention to the parallelism of the tape and the glue seam.

[0101] (2) When applying glue to glass, first cut the corresponding bevel of the silicone glue of the specified brand according to the size of the glue seam. The glue should be applied evenly. The operation sequence is generally: vertical glue seam, from top to bottom.

[0102] (3) After the glue is filled, check whether there are bubbles in the glue joint. If there are, deal with them in time to eliminate the bubbles. After the glue is injected, the glue joint and the substrate must be firmly bonded without pores, and the glue joint must be flat and smooth. After the surface is modified, quickly tear off the masking tape on the glass. After the glue is cured, clean the inner and outer glass and make protective signs. After the glass surface is cleaned, report to the supervisor, Party A, design, and other relevant departments for acceptance.

[0103] 4. Glass hoisting

[0104] Lifting equipment: main crane and electric winch

[0105] 1. Transport equipment

[0106] Steel frames, glass panels and other extra-long and extra-wide materials that cannot be transported by tower cranes or construction elevators are transported vertically by cranes, and then transported to various construction areas by engineering transport vehicles or manually.

[0107] 2. Hoisting method

[0108] All extra-long and extra-wide materials and steel skeletons used for construction are hoisted by two-point binding method. When hoisting the rod, the angle between the wire rope and the axis of the rod is 45°.

[0109] Step 18: Structural Monitoring and Acceptance

[0110] Deformation monitoring

[0111] (1) Monitoring instruments

[0112] The deformation is monitored by using a total station and sticking reflective sheets on the ear plates to monitor the deformation of the boundary components of the cable net.

[0113] (2) Monitoring point layout

[0114] The monitoring point is arranged in the middle of the span. Reflective sheets are fully pasted on the ear plates. At the end of each stage of tensioning, the deformation of the steel structure is measured. During the tensioning process, the measured deformation is compared with the calculated theoretical deformation. If the difference is large (more than 20% and more than 5mm), the tensioning is stopped and reported immediately to the general contractor, supervisor and design institute. The tensioning can be continued only after the cause is found and the solution is determined.

[0115] Use process monitoring and maintenance

[0116] During the construction and use period, the internal force of cable 2 needs to be tested regularly to understand the safety performance of the structure and ensure the safe use of the structure in the future.

[0117] According to the requirements of 7.6.2 of the Technical Code for Cable Structures: During the use of cable structures, due to the influence of seasonal temperature changes, meteorological phenomena such as wind, rain, ice and snow, dynamic loads, creep of concrete, cable relaxation and support settlement, etc., the prestress of cable 2 will be reduced. Regular inspections can be carried out as needed. It is recommended to conduct inspections once every six months after the completion of the structure and once a year after the completion of cable 2. No observation is required after stability.

[0118] In addition, it is necessary to conduct regular appearance inspections on the cables and nodes to ensure that various materials are safe and effective, the anti-corrosion meets the design requirements, and the structure is safe and reliable.

[0119] 4. Appearance inspection

[0120] The contents of the structural appearance inspection include: appearance inspection of cables 2 (cable body and anchor), nodes, etc. and related surface paint inspection, etc., to ensure that various materials are safe and effective, the anti-corrosion meets the design requirements, and the structure is safe and reliable. The specific contents are as follows.

[0121] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A cable curtain wall construction method, characterized in that: The steps include: Add temporary loads to the top of the curtain wall; Arrange a plurality of cables on the curtain wall, and determine the installation positions and tensioning sequence of the cables according to construction requirements; Providing a cable tensioning machine, and tensioning the cable by the cable tensioning machine until the cable is tensioned to a tension required by design; After the tensioning of the cables is completed, backfill construction is carried out on the top of the curtain wall and the temporary loads at the corresponding positions are gradually removed until the construction of the top of the curtain wall is completed.

2. A cable curtain wall construction method according to claim 1, characterized in that: After tensioning, the tension Fi of the cable is: Fi = F0 + Fi loss; Wherein F0 is the designed prestress of the cable, and Fi loss is the internal stress lost by the cable with the corresponding number after tensioning.

3. A cable curtain wall construction method according to claim 2, characterized in that: The Fi loss is calculated according to the following formula: Where Δi is the deformation of the cable, Li is the length of the cable, E is the elastic modulus, and A is the cross-sectional area of ​​the cable.

4. A cable curtain wall construction method according to claim 1, characterized in that: When installing the curtain wall, a total station is provided, and positioning and measuring of the curtain wall are performed by the total station.

5. The cable curtain wall construction method according to claim 1 is characterized in that: When installing the curtain wall, the construction process is simulated by using MIDASGEN software.

6. A cable curtain wall construction method according to claim 1, characterized in that: When the cables are arranged, each cable is numbered.

7. The cable curtain wall construction method according to claim 1 is characterized in that: During the backfilling construction of the curtain wall, the cables are tested, and if the internal stress of the cables is lost, the cables are tensioned again.

8. The cable curtain wall construction method according to claim 1 is characterized in that: When a temporary load is added, a water tank is provided and arranged on the top of the curtain wall. When the curtain wall is backfilled, the water in the water tank is gradually discharged.

9. The cable curtain wall construction method according to claim 1, characterized in that: Before the cables are arranged on the curtain wall, various structures of the curtain wall are checked. If the design of the curtain wall does not meet the design specifications, the curtain wall is adjusted.

10. A cable curtain wall construction method according to claim 1, characterized in that: When setting the cable, a reflective sheet is set at a fixed position of the cable, and the initial coordinates are recorded. After the cable is tensioned, measurement and calibration are performed using the reflective sheet.

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