Bent and twisted section hoisting method

Abstract

The invention discloses a bent and twisted section hoisting method, which comprises the following steps of: hoisting steel tower sections by utilizing a crawler crane, adjusting postures, hoisting to the upper part of a tower column a, accurately adjusting by adopting a chain block and a three-way jack, respectively assembling the steel tower sections of tower limbs A and B according to a standard process, respectively installing a stay rope on the tower limbs A and B, and carrying out linear adjustment on the tower column. A second stay cable is installed on the tower limb A and the tower limb B and temporarily tensioned, a second cross brace is installed, a fourth stay cable of the tower limb A is installed and temporarily tensioned, the line shape of a closure opening is adjusted, the closure opening is spliced into a whole on the ground, the whole closure opening is hoisted to a designed position through a crawler crane, steel tower closure construction is completed, the cross brace, the crawler crane and other temporary facilities are dismantled, and permanent cable installation and tensioning are completed. The method is scientific and reasonable in design, a cross brace and longitudinal inhaul cable balance system is established, the segment butt joint posture is adjusted through the hydraulic balance lifting appliance, and the construction precision, structural stability and construction safety of the steel tower can be effectively guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of steel structure construction, and particularly relates to a method for hoisting a bending and torsion segment. Background Art

[0002] The towers of unusual landscape cable-stayed bridges are the core structures that express the aesthetics of the entire bridge design. They often feature highly expressive spatial distortions, resulting in complex structural shapes and load-bearing requirements. Steel structures are typically used to meet these unique appearance and load-bearing requirements. Unlike regular bridge towers, the axis of unusual steel towers gradually evolves from a flat curve to a spatially twisted curve. Furthermore, their height, large cross-sectional dimensions, and weight make them challenging to position and adjust mid-air.

[0003] For spatial irregular and twisted steel tower structures, conventional hoisting methods require the construction of ground-based scaffolding and construction platforms for segment docking. The construction of ground-based scaffolding and construction platforms not only prolongs the construction period, but also increases material and labor costs. In addition, during the hoisting process, the main tower limbs will undergo three-dimensional deformation due to the combined influence of complex factors such as the dead weight of the assembled segments, welding deformation of the welds, construction loads, temperature and wind loads. Adjustments to the three axial coordinates are required, which makes it impossible to guarantee the accuracy of the aerial alignment of the tower segments. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for hoisting a bending and torsion segment to at least solve some of the above technical problems.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for hoisting a bending and twisting segment comprises the following steps:

[0007] Step 1: Use a crawler crane to lift the assembled steel tower segments;

[0008] Step 2: Use the lifting sling to lift the segment, adjust the posture, lift it above the A tower column, and complete the assembly between the segments;

[0009] Step 3: Use hand chain hoist and three-way jack in conjunction with lifting equipment to accurately adjust the segment;

[0010] Step 4: Assemble the A and B tower limb steel tower segments according to the standard process;

[0011] Step 5: Install a cable on each of the A and B tower legs, and perform temporary tensioning according to monitoring instructions to adjust the tower column linearity. The specific installation position of the cable installation segment is determined through finite element simulation;

[0012] Step 6: Install the second cable on the A and B tower legs and complete the temporary tensioning of the cable according to the monitoring instructions;

[0013] Step 7: Install the second cross brace, and install the monitoring instructions to carry out the tower limb top operation, install the fourth cable of the A tower limb, and complete the temporary tensioning of the cable according to the monitoring instructions;

[0014] Step 8: Adjust the line shape of the closure mouth, assemble the closure sections into a whole on the ground, and use a crawler crane to lift them to the designed position to complete the steel tower closure construction;

[0015] Step 9: Remove the cross brace, crawler crane and other temporary facilities, complete the permanent cable installation and tensioning according to the construction process, and complete the main tower construction.

[0016] Furthermore, in step 2, the segment lifting adopts a four-point automatic balancing and positioning hydraulic lifting device, which includes an upper lifting belt, a hydraulic cylinder and a lower lifting belt. The four lower lifting belts are connected to the upper lifting ears of the tower segment, the hydraulic cylinder is connected between the upper lifting belt and the lower lifting belt, and the upper lifting belt is connected to the lifting equipment hook.

[0017] Furthermore, the hydraulic cylinder and the oil pump are connected through an oil pipe. The installation posture of the tower segment can be accurately adjusted by using different sling lengths and the hydraulic cylinder. The sling can adapt to the posture adjustment of the segment within 20°.

[0018] Furthermore, in step three, when the hoisting segment is 1m away from the installed segment, the segment to be installed is slowly lowered by loosening the hook with the help of a hand hoist and the hoisting equipment, and temporarily placed on a three-way jack; the segment is precisely adjusted by the three-way jack, and the hoisting equipment does not loosen the hook at this time to complete the precise adjustment of the segment.

[0019] Furthermore, in step six, the first cross brace is installed between the steel tower columns. The first cross brace is hoisted by a crawler crane to the brackets at both ends and temporarily placed. After the installation of the first cross brace is completed, the jack is arranged at the top, and two jacks are set at the pushing end for positioning. The center of the jack piston is aligned with the center of the cross brace.

[0020] Furthermore, during jacking, graded pressure control is performed according to the calculated pre-jacking force required.

[0021] Furthermore, the graded pressure is graded in 10 MPa steps.

[0022] Furthermore, when reaching the last four levels of the designed pre-jacking force, graded pressure control is performed with a step difference of 5 MPa.

[0023] Furthermore, after the cross brace pushing operation is completed, the cushion block structure is lifted to the designed position using a crawler crane and welded and fixed, connecting it to one side tower column into a whole.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The design of the present invention is scientific and reasonable. By establishing a horizontal brace plus longitudinal cable balancing system and using a hydraulic balancing sling to adjust the segment docking posture, the construction accuracy, structural stability and construction safety of the steel tower can be effectively ensured. During the steel tower installation process, there is no need to set up a ground scaffolding, and the cantilever lifting and positioning of the steel tower can be fine-tuned. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic flow chart of the bending and torsion segment lifting method of the present invention.

[0027] Figure 2 This is a schematic diagram of the present invention using a crawler crane to lift the assembled steel tower segments.

[0028] Figure 3 The figure is a schematic elevation view of the sling of the present invention (dimensions in mm).

[0029] Figure 4 Schematic diagram of the cross section of the sling of the present invention (dimensions in mm).

[0030] Figure 5 Schematic diagram of the lifting sling of the present invention (dimensions in mm).

[0031] Figure 6 It is a schematic diagram of the sling of the present invention.

[0032] Figure 7 This is a structural diagram of the telescopic cylinder of the present invention (dimensions in mm).

[0033] Figure 8 It is a schematic diagram of the planar arrangement of the tower segment lifting lugs of the present invention.

[0034] Figure 9 This is a schematic diagram of the arrangement of the lifting lugs of the present invention.

[0035] Figure 10 This is a schematic diagram of the segment docking of the present invention Figure 1 .

[0036] Figure 11 Schematic diagram of segment docking of the present invention Figure 2 .

[0037] Figure 12 This is a schematic diagram of assembling the A and B tower limb steel tower segments according to the standard process of the present invention.

[0038] Figure 13 This is a schematic diagram of step five of the present invention.

[0039] Figure 14 This is a schematic diagram of step six of the present invention.

[0040] Figure 15 This is a schematic elevation diagram of the crossbeam installation of the present invention.

[0041] Figure 16 It is a schematic diagram of the cross brace placement and corbel of the present invention.

[0042] Figure 17 This is a schematic diagram of step seven of the present invention.

[0043] Figure 18 This is a schematic diagram of step eight of the present invention. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] like Figure 1-8 As shown, the present invention provides a method for hoisting a bending and twisting segment, comprising the following steps:

[0046] Step 1: Use a crawler crane to lift the assembled steel tower segments.

[0047] Step 2: Use the lifting sling to lift the segment, adjust the posture, lift it above the A tower column, and complete the assembly between the segments.

[0048] The segment lifting adopts a four-point automatic balancing and positioning hydraulic spreader, which includes an upper lifting strap, a hydraulic cylinder and a lower lifting strap. The four lower lifting straps are connected to the upper lifting ears of the tower segment, the hydraulic cylinder is connected between the upper and lower lifting straps, and the upper lifting strap is connected to the hook of the lifting equipment.

[0049] The hydraulic cylinder and oil pump are connected by oil pipes. The installation posture of the tower segment can be accurately adjusted by different sling lengths and hydraulic cylinders. The sling can adapt to the posture adjustment of the segment within 20°.

[0050] Step 3: Use hand hoists and three-way jacks in conjunction with lifting equipment to precisely adjust the segments.

[0051] When the hoisting segment is 1m away from the installed segment, the segment to be installed is slowly lowered by pulling with the hand hoist and coordinating with the hoisting equipment, and temporarily placed on the three-way jack; the segment is accurately adjusted by the three-way jack, and the hoisting equipment does not release the hook at this time to complete the precise adjustment of the segment.

[0052] Step 4: Assemble the A and B tower limb steel tower segments separately according to the standard process.

[0053] Step 5: Install a cable on each of the A and B tower legs, and perform temporary tensioning according to the monitoring instructions to adjust the tower column line. The specific installation position of the cable installation segment is determined through finite element simulation.

[0054] Step 6: Install the second cable on the A and B tower legs, and complete the temporary tensioning of the cable according to the monitoring instructions.

[0055] Install the first cross brace between the steel tower columns. Use a crawler crane to lift the first cross brace to the bull legs at both ends and temporarily place it. After the installation of the first cross brace is completed, arrange the jack at the top and set two jacks at the pushing end to position them. The center of the jack piston is aligned with the center of the cross brace.

[0056] During jacking, graded pressure control is performed according to the calculated pre-jacking force required.

[0057] The graded pressure is graded in 10MPa steps.

[0058] When reaching the last four levels of designed pre-jacking force, graded pressure control is performed with a step difference of 5 MPa.

[0059] After the cross brace pushing operation is completed, the cushion block structure is lifted to the designed position using a crawler crane and welded and fixed, connecting it to one side tower column into a whole.

[0060] Step 7. Install the second cross brace and perform the tower limb top-up operation according to the monitoring instructions. Install the fourth cable of tower limb A and complete the temporary tensioning of the cable according to the monitoring instructions.

[0061] Step 8. Adjust the line shape of the joint mouth, assemble the joint sections into a whole on the ground, use a crawler crane to lift them to the designed position, and complete the steel tower joint construction.

[0062] Step 9: Remove the cross brace, crawler crane and other temporary facilities, complete the permanent cable installation and tensioning according to the construction process, and complete the main tower construction.

[0063] The design of the present invention is scientific and reasonable. By establishing a horizontal brace plus longitudinal cable balancing system and using a hydraulic balancing sling to adjust the segment docking posture, the construction accuracy, structural stability and construction safety of the steel tower can be effectively ensured. During the steel tower installation process, there is no need to set up a ground scaffolding, and the cantilever lifting and positioning of the steel tower can be fine-tuned.

[0064] In order to ensure the stability and linear control when hoisting the tower segments during the construction process of the present invention, two measures are adopted during the hoisting process: horizontal internal support and longitudinal prestressed temporary cable tensioning steel strands to ensure the horizontal and vertical stability of the main tower.

[0065] According to calculations and analysis, when the main tower segments are hoisted to a certain height, transverse internal supports and longitudinal temporary cables are set up to form the internal support and tensioning system of the steel main tower.

[0066] The main tower of the present invention is a spatially twisted structure, and the aerial posture of the tower segment needs to be continuously adjusted during the hoisting process. During the hoisting process, a total of 4 lifting points are set on the tower segment, and the posture adjustment is achieved through a four-point automatic balancing and positioning hydraulic spreader.

[0067] During the steel tower installation process of the present invention, there is no need to set up a ground scaffolding, and fine adjustment of the steel tower cantilever hoisting position can be achieved.

[0068] The present invention provides a method for hoisting a bending and torsion segment, specifically comprising:

[0069] like Figure 2 As shown, the assembled steel tower segments are lifted using a crawler crane.

[0070] like Figure 3-Figure 9 As shown, the segments are lifted using slings (slings + cylinders + shackles), and after adjusting their posture, they are lifted above tower column A to complete the assembly between segments.

[0071] The segment lifting adopts a four-point automatic balancing positioning hydraulic lifting device, which consists of an upper lifting strap, a cylinder, a lower lifting strap and a shackle. The four lower lifting straps are connected to the lifting ears on the tower segment. The cylinder is set between the upper and lower lifting straps, and the upper lifting strap is connected to the equipment hook.

[0072] The telescopic cylinder is connected to the oil pump through an oil pipe, and the oil pump is connected to the power supply. The installation posture of the tower segment can be accurately adjusted by different sling lengths and the oil cylinder. The sling can adapt to the posture adjustment of the segment within 20°.

[0073] like Figure 10 and Figure 11 As shown, when the hoisting segment is 1m away from the installed segment, the segment to be installed is lowered by pulling with a hand hoist and slowly unhooking the equipment, and temporarily placed on a three-way jack. The segment is precisely adjusted using the three-way jack, and the equipment does not release the hook at this time to complete the precise adjustment of the segment.

[0074] like Figure 12 As shown, according to the standard process, the A and B tower limb steel tower segments are assembled separately.

[0075] like Figure 13 As shown, a cable is installed on each of the AB tower legs, and temporary tensioning is performed according to monitoring instructions to adjust the tower column linearity. The specific installation position of the cable installation segment is determined through finite element simulation.

[0076] like Figure 14-16 As shown, the second cable is installed on the A and B tower legs, and the temporary tensioning of the cable is completed according to the monitoring instructions; the first cross brace is installed between the steel tower columns, and the cross brace is temporarily placed on the brackets at both ends using a crawler crane. After the cross brace is installed, the jack is arranged at the top, and two jacks are set at the pushing end to position them. The center of the jack piston is aligned with the center of the cross brace.

[0077] During jacking, graded pressure control is performed according to the pre-jacking force required by calculation. The graded pressure is performed in 10MPa steps, and the last few steps close to the designed pre-jacking force are performed in 5MPa steps.

[0078] After the cross brace pushing operation is completed, the cushion block structure is lifted to the designed position using a crawler crane, and fixed by welding, connecting it to one side tower column into a whole.

[0079] Figure 16 This is a schematic diagram of the cross brace placement and the bracket of the present invention, which is also Figure 15 Schematic diagram of the left end.

[0080] like Figure 17 As shown, install the second cross brace and perform the tower leg top-up operation according to the monitoring instructions. Install the fourth cable of Tower A leg and complete the temporary tensioning of the cable according to the monitoring instructions.

[0081] like Figure 18 As shown, the line shape of the closure mouth is adjusted, the closure sections are assembled into a whole on the ground, and a crawler crane is used to lift them to the designed position to complete the steel tower closure construction.

[0082] Remove the cross braces, crawler cranes and other temporary facilities, complete the installation and tensioning of permanent cables according to the construction process, and complete the main tower construction.

[0083] The design of the present invention is scientific and reasonable. By establishing a horizontal brace plus longitudinal cable balancing system and using a hydraulic balancing sling to adjust the segment docking posture, the construction accuracy, structural stability and construction safety of the steel tower can be effectively ensured. During the steel tower installation process, there is no need to set up a ground scaffolding, and the cantilever lifting and positioning of the steel tower can be fine-tuned.

[0084] In order to ensure the stability and linear control when hoisting the tower segments during the construction process of the present invention, two measures are adopted during the hoisting process: horizontal internal support and longitudinal prestressed temporary cable tensioning steel strands to ensure the horizontal and vertical stability of the main tower.

[0085] According to calculations and analysis, when the main tower segments are hoisted to a certain height, transverse internal supports and longitudinal temporary cables are set up to form the internal support and tensioning system of the steel main tower.

[0086] The main tower of the present invention is a spatially twisted structure, and the aerial posture of the tower segment needs to be continuously adjusted during the hoisting process. During the hoisting process, a total of 4 lifting points are set on the tower segment, and the posture adjustment is achieved through a four-point automatic balancing and positioning hydraulic spreader.

[0087] During the steel tower installation process of the present invention, there is no need to set up a ground scaffolding, and fine adjustment of the steel tower cantilever hoisting position can be achieved.

[0088] Finally, it should be noted that the above embodiments are merely preferred embodiments of the present invention and are intended to illustrate the technical solutions of the present invention, not to limit the present invention, and certainly not to limit the scope of the present invention. Any modifications or improvements that are insignificant to the main design concept and spirit of the present invention, provided that the technical problems they solve are consistent with the present invention, shall be included within the scope of protection of the present invention. Furthermore, any direct or indirect application of the technical solutions of the present invention to other related technical fields shall also be included within the scope of protection of the present invention.

Claims

1. A method for hoisting a bending and twisting segment, characterized in that: The following steps are involved: Step 1: Use a crawler crane to lift the assembled steel tower segments; Step 2: Use the lifting sling to lift the segment, adjust the posture, lift it above the A tower column, and complete the assembly between the segments; Step 3: Use hand chain hoist and three-way jack in conjunction with lifting equipment to accurately adjust the segment; Step 4: Assemble the A and B tower limb steel tower segments according to the standard process; Step 5: Install a cable on each of the A and B tower legs, and perform temporary tensioning according to monitoring instructions to adjust the tower column linearity. The specific installation position of the cable installation segment is determined through finite element simulation; Step 6: Install the second cable on the A and B tower legs and complete the temporary tensioning of the cable according to the monitoring instructions; Step 7: Install the second cross brace, and install the monitoring instructions to carry out the tower limb top operation, install the fourth cable of the A tower limb, and complete the temporary tensioning of the cable according to the monitoring instructions; Step 8: Adjust the line shape of the closure mouth, assemble the closure sections into a whole on the ground, and use a crawler crane to lift them to the designed position to complete the steel tower closure construction; Step 9: Remove the cross brace, crawler crane and other temporary facilities, complete the permanent cable installation and tensioning according to the construction process, and complete the main tower construction.

2. A method for hoisting a bending and torsion segment according to claim 1, characterized in that: In step 2, the segment lifting adopts a four-point automatic balancing and positioning hydraulic lifting device, which includes an upper lifting belt, a hydraulic cylinder and a lower lifting belt. The four lower lifting belts are connected to the upper lifting ears of the tower segment, the hydraulic cylinder is connected between the upper lifting belt and the lower lifting belt, and the upper lifting belt is connected to the lifting equipment hook.

3. A method for hoisting a bending and torsion segment according to claim 2, characterized in that: The hydraulic cylinder and oil pump are connected by oil pipes. The installation posture of the tower segment can be accurately adjusted by different sling lengths and hydraulic cylinders. The sling can adapt to the posture adjustment of the segment within 20°.

4. A method for hoisting a bending and torsion segment according to claim 1, characterized in that: In step three, when the hoisting segment is 1m away from the installed segment, the segment to be installed is slowly lowered by pulling with the hand hoist in conjunction with the hoisting equipment and temporarily placed on the three-way jack; the segment is accurately adjusted by the three-way jack, and the hoisting equipment does not release the hook at this time to complete the precise adjustment of the segment.

5. A method for hoisting a bending and torsion segment according to claim 1, characterized in that: In step six, the first cross brace between the steel tower columns is installed. The first cross brace is hoisted by a crawler crane to the brackets at both ends and temporarily placed. After the installation of the first cross brace is completed, the jack is arranged at the top, and two jacks are set at the pushing end for positioning. The center of the jack piston is aligned with the center of the cross brace.

6. A method for hoisting a bending and torsion segment according to claim 5, characterized in that: During jacking, graded pressure control is performed according to the calculated pre-jacking force required.

7. A method for hoisting a bending and torsion segment according to claim 6, characterized in that: The graded pressure is graded in 10MPa steps.

8. A method for hoisting a bending and torsion segment according to claim 7, characterized in that: When reaching the last four levels of designed pre-jacking force, graded pressure control is performed with a step difference of 5 MPa.

9. A method for hoisting a bending and torsion segment according to claim 5, characterized in that: After the cross brace pushing operation is completed, the cushion block structure is lifted to the designed position using a crawler crane and welded and fixed, connecting it to one side tower column into a whole.

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