Steel box girder lifting system under limited space condition

Abstract

The invention discloses a steel box girder lifting system under a limited space condition. The steel box girder lifting system comprises two folding arm cranes and a control system, the two folding arm cranes are located on the two sides of the supporting structure respectively. A distance sensor is arranged at the top end of a main arm of each folding arm crane; two folding arm lifting points are arranged at the top of the steel box girder, a PSD position sensor is arranged at the position, close to each folding arm lifting point, of the top of the steel box girder, and audible and visual alarms are arranged on the distance sensor and the PSD position sensors; the control system comprises a synchronous control module and a control processing module, the synchronous control module is connected with the two folding arm cranes to control the two folding arm cranes to work cooperatively, and the control processing module is connected with the synchronous control module, a distance sensor, a PSD position sensor and an audible and visual alarm. According to the system, under the conditions that the system is close to a railway and the clear height below a viaduct is limited, the two folding arm cranes are used for lifting the steel box girder cooperatively, and safe and efficient construction is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of steel structure construction, and in particular to a steel box girder lifting system under space-constrained conditions. Background Art

[0002] In the field of bridge construction, especially in the construction of new steel box girder bridges adjacent to existing railway lines, traditional straight-arm cranes are difficult to meet the requirements of railway operation safety limits due to their large overturning radius; at the same time, the working space under the upper viaduct where the rotation construction has been completed is limited, which further restricts the use of straight-arm cranes and poses a major safety hazard. Summary of the invention

[0003] In response to the above-mentioned problems, the present invention provides a steel box girder lifting system under space-constrained conditions, which aims to use two folding arm cranes to collaboratively lift steel box girders under conditions of being close to railways and with limited clear height under viaducts, so as to ensure safe and efficient construction while meeting the safety requirements of railway operations.

[0004] A steel box girder lifting system under space-constrained conditions is used to lift the steel box girder onto a supporting structure, the supporting structure is adjacent to an existing railway, and a viaduct is arranged above the supporting structure, wherein the lifting system comprises: two folding arm cranes and a control system;

[0005] The two folding arm cranes are respectively located on both sides of the supporting structure, and the overturning track of any one of the folding arm cranes is located outside the safety limit of the existing railway, and the operating radius of any one of the folding arm cranes at the lifting position and the in-position position of the steel box girder is smaller than the maximum operating radius of the folding arm crane;

[0006] A distance sensor is provided at the top of the main arm of each folding arm crane, and the distance sensor is used to monitor the distance between the top of the main arm of the folding arm crane and the bottom surface of the viaduct in real time; two folding arm crane lifting points are provided at the top of the steel box girder, and a PSD position sensor is provided near the top of the steel box girder and each of the folding arm crane lifting points, and sound and light alarms are provided on the distance sensor and the PSD position sensor;

[0007] The control system includes a synchronous control module and a control processing module. The synchronous control modules are respectively connected to the two folding arm cranes to control the two folding arm cranes to work together during the steel box girder hoisting process. The control processing module is respectively connected to the synchronous control module, the distance sensor, the PSD position sensor and the sound and light alarm to adjust the control parameters of the synchronous control module according to the detection data of the distance sensor and the PSD position sensor, and control the sound and light alarm located on the distance sensor to alarm when the distance detected by the distance sensor is less than a preset safety value, and control the sound and light alarm located on the PSD position sensor to alarm when the difference between the data detected by the two PSD position sensors is greater than a preset threshold.

[0008] In some of the embodiments, a guy rope is connected between the upper part of the main arm of each folding arm crane and the ground, and the guy rope and the existing railway are respectively located on two opposite sides of the folding arm crane.

[0009] In some of these embodiments, the guy line is anchored to the ground.

[0010] In some of the embodiments, a hand winch is provided on the guy rope to tighten the tightness of the guy rope through the hand winch.

[0011] In some of the embodiments, a damping device and an anti-overturning self-locking device are provided on the guy rope.

[0012] In some embodiments, the preset safety value is 0.5m.

[0013] In some embodiments, the preset threshold is 0.2 m.

[0014] In some of the embodiments, the distance between the overturning trajectory of the folding crane and the safety limit of the existing railway is greater than 1.5m.

[0015] In some of the embodiments, the load factors of the two folding arm cranes are both lower than 70%.

[0016] In some of the embodiments, the support structure is a support tower or a bridge pier.

[0017] Compared with the prior art, the above invention has at least one of the following advantages or beneficial effects:

[0018] 1. Improve safety: By ensuring that the tipping trajectory and operating radius of the knuckle boom crane meet the requirements, combined with real-time distance monitoring and synchronous control, safety hazards during the lifting process are effectively avoided, ensuring that railway operations are not affected.

[0019] 2. Enhanced adaptability: It is particularly suitable for complex environments with limited clearance close to existing railways and under viaducts, which broadens the application scenarios of folding arm cranes in bridge construction.

[0020] 3. Improve efficiency: The double-folding arm crane works in coordination with sensor monitoring and sound and light alarms to improve the accuracy and efficiency of lifting operations.

[0021] 4. Increase redundant safety design: Auxiliary safety measures such as guy ropes, anti-overturning self-locking devices, etc. provide additional safety protection for the lifting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention and its features, appearance and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts in all the drawings. The drawings are not drawn to scale, and emphasis is placed on illustrating the subject matter of the present invention.

[0023] Figure 1 It is a front view of the steel box girder lifting system under space-constrained conditions in an embodiment of the present invention;

[0024] Figure 2 A top view of a steel box girder lifting system under space-constrained conditions in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of the overturning trajectory of the double-knuckle boom crane in the steel box girder lifting system under space-constrained conditions in an embodiment of the present invention;

[0026] Figure 4 Schematic diagram of the structure of wind restraint of folding arm cable in an embodiment of the present invention;

[0027] Among them, 1. Steel box girder in lifting position; 1', Steel box girder in in-place position; 11, Bridge pier; 12, Support tower; 2, Viaduct; 3A, First folding arm crane; 3B is the second folding arm crane; 31, Outrigger; 32, Main arm in lifting state; 32', Main arm in in-place state; 321, Transverse swing amplitude of main arm; 33, Hoisting wire rope; 34, Overturning radius of folding arm crane; 35, Overturning trajectory of folding arm crane; 4, PSD position sensor; 5, Distance sensor; 6, Sound and light alarm; 7, Cable wind rope; 71, Hand winch; 72, Ground anchor; 8, Damping device; 9, Anti-overturning self-locking device; 10, Existing railway line; 101, Safety boundary of existing railway. DETAILED DESCRIPTION

[0028] The present invention is further described below with reference to the accompanying drawings and specific embodiments, but is not intended to be a limitation of the present invention.

[0029] like Figures 1 to 4As shown, the present invention discloses a steel box girder lifting system under space-constrained conditions, which is used to lift the steel box girder onto a supporting structure. According to the installation position of the steel box girder, the supporting structure can be a supporting tower 12 or a bridge pier 11; it can be more than two supporting towers 12, or it can be a bridge pier 11 and a supporting tower 12; that is, the steel box girder to be lifted is lifted from the lifting position of the steel box girder (1 is the steel box girder in the lifting position) to the in-position position of the steel box girder at the top of the supporting structure (1' is the steel box girder in the in-position position), the supporting structure is adjacent to an existing railway line 10, and an elevated bridge 2 is arranged above the supporting structure, the elevated bridge 2 is a main line rotating bridge that has been completed, and the working space on the top of the steel box girder is limited.

[0030] The lifting system comprises: two folding arm cranes (respectively a first folding arm crane 3A and a second folding arm crane 3B) and a control system; the two folding arm cranes are respectively located on both sides of the supporting structure, and the overturning track of any folding arm crane is located outside the safety limit 101 of the existing railway (the safety limit 101 of the existing railway is outside the existing railway line 10, which is the safety limit set by the railway department), and the operating radius of any folding arm crane in the lifting position and the positioning position of the steel box girder is less than the maximum operating radius of the folding arm crane; specifically, when the steel box girder is in the lifting position, the operating radius of the two folding arm cranes is less than the maximum operating radius of the two folding arm cranes. The radiuses of the two folding arm cranes are RA1 and RB1 respectively (RA1 is the operating radius of the lifting position of the folding arm crane A; RB1 is the operating radius of the lifting position of the second folding arm crane 3B). When the steel box girder is in position, the operating radius of the two folding arm cranes are RA2 and RB2 respectively (RA2 is the operating radius of the first folding arm crane 3A in position; RB2 is the operating radius of the second folding arm crane 3B in position). The limit operating radiuses of the two folding arm cranes are RA0 and RB0 respectively (RA0 is the limit operating radius of the first folding arm crane 3A; RB0 is the limit operating radius of the second folding arm crane 3B). When in use, the two folding arm cranes lift the steel box girder with a certain swing amplitude. During lifting, the legs 31 are extended and supported on a solid ground, and the main arm of the folding arm crane is tilted or swung horizontally for lifting operations, and is connected to the lifting points of the folding arm cranes on the steel box girder through the lifting wire rope 33. The tipping radius 34 of the folding arm crane is the radius of rotation of the main arm end of the folding arm crane around the root of the support leg 31 when the folding arm crane is in the hoisting state, forming a tipping trajectory once it tips over; 32 is the main arm in the hoisting state; 32' is the main arm in the in-place state; 321 is the lateral swing amplitude of the main arm.

[0031] A high-precision distance sensor 5 is provided at the top of the main arm of each folding arm crane. The distance sensor 5 is used to monitor the distance H between the top of the main arm of the folding arm crane and the bottom surface of the viaduct 2 in real time, and feed back the detection data to the control system; two folding arm crane lifting points are provided on the top of the steel box girder (that is, the top plate of the steel box girder), the distance D between the two folding arm crane lifting points on the top plate of the steel box girder is a fixed value, and a PSD position sensor 4 is provided near each folding arm crane lifting point on the top of the steel box girder (that is, the two PSD position sensors 4 are respectively provided on the top surface of the steel box girder, and the two PSD position sensors 4 are respectively located near the two folding arm crane lifting points), the two PSD position sensors 4 can monitor the position data near the folding arm crane lifting points on the steel box girder in real time, and feed back the detection data to the control system; and the distance sensor 5 and the PSD position sensor 4 are both provided with an audible and visual alarm 6, the PSD position sensor 4 is linked to the audible and visual alarm 6 thereon, and the distance sensor 5 is linked to the audible and visual alarm thereon.

[0032] The control system includes a synchronous control module and a control processing module. The synchronous control module is respectively connected to the two folding arm cranes to control the two folding arm cranes to work together during the steel box girder hoisting process. The control processing module is respectively connected to the synchronous control module, the distance sensor 5, the PSD position sensor 4 and the sound and light alarm 6 to adjust the control parameters of the synchronous control module according to the detection data of the distance sensor 5 and the PSD position sensor 4, and control the sound and light alarm 6 located on the distance sensor 5 to alarm after the distance H detected by the distance sensor 5 is less than the preset safety value. When the distance H is less than 0.5m, the sound and light alarm 6 located on the distance sensor 5 immediately starts to alarm, reminding the operator to take corresponding measures; and when the difference h between the data detected by the two PSD position sensors 4 is greater than the preset threshold, the sound and light alarm 6 located on the PSD position sensor 4 is controlled to alarm. Specifically, when the difference h between the data detected by the two PSD position sensors 4 is greater than 0.2m, the sound and light alarm 6 located on the PSD position sensor 4 is activated to remind the operator to pay attention to the inclination of the steel box girder and take timely measures to adjust it.

[0033] In an embodiment of the present invention, a certain safety distance S is left between the overturning trajectory 35 of the above-mentioned folding arm crane and the safety limit 101 of the existing railway; specifically, the distance between the overturning trajectory of the folding crane and the safety limit of the railway line is greater than 1.5m; at the same time, in order to ensure that the folding arm crane does not overturn toward the railway, the main arm of the above-mentioned folding arm crane is provided with a cable wind rope 7, that is, a cable wind rope 7 is connected between the upper part of the main arm of each folding arm crane and the ground, and the cable wind rope 7 and the existing railway line 10 are respectively located on two sides of the folding arm crane that are relatively arranged, and the cable wind rope 7 is anchored to the ground by a ground anchor 72, and an anti-self-locking device, a hand winch 71 and a damping device 8 are provided on the cable wind rope 7 to tighten the tightness of the cable wind rope 7 by the hand winch 71.

[0034] In some of the embodiments, the load factors of the two folding arm cranes are both lower than 70%.

[0035] Specifically, when the two folding arm cranes are respectively placed on both sides of the support tower 12 at the design position of the steel box girder, the positions need to be accurately positioned according to the actual situation on site, crane performance, safety distance and other factors to ensure that the overturning trajectory 35 of the folding arm crane is outside the safety limit 101 of the existing railway. At the same time, the position selection also needs to consider the ground bearing capacity to ensure that the crane will not have an accident due to ground collapse during operation. According to the lifting position and the position in place of the steel box girder, the operating radius of the two folding arm cranes is accurately calculated. When lifting, the operating radius of the first folding arm crane 3A and B is RA1 and RB1 respectively; when in place, the operating radius is RA2 and RB2 respectively. These operating radii must be strictly less than the limit operating radius of the folding arm crane. The limit operating radius of the two folding arm cranes is RA0 and RB0 respectively, to ensure the safety and stability of the lifting process. The swing amplitude of the main arm of the folding arm crane is determined according to the operating radius and the distance D between the two folding arm crane lifting points on the steel box girder. During the hoisting process, the swing arm amplitude should be reasonably adjusted according to the actual aerial position of the lifting point of the folding arm crane to ensure the coordinated operation of the two folding arm cranes and the stable hoisting of the steel box girder. At the same time, the distance between the rotation center of the folding arm crane and the lifting point in place (i.e., the operating radius of the folding arm crane) should be considered to ensure accurate control during the hoisting process. In addition, when determining the operating radius and swing arm amplitude, the influence of external factors such as wind load and dynamic load on the stability of the crane should also be considered. It should be verified by calculation or experiment to ensure that the crane can remain stable under various working conditions. During the hoisting process, the operating radius and swing arm amplitude of the two folding arm cranes need to be monitored in real time to ensure that they are always within the safe range. If any abnormality is found, the hoisting should be stopped immediately, and corresponding adjustments and processing should be made. During the hoisting process, the main arm of the folding arm crane needs to adjust the elevation or depression angle in time according to the change of the operating radius to ensure that the safe distance d≥0 between the top of the main arm and the bottom surface of the upper viaduct 2. This needs to be achieved through precise control systems and sensors. The above control system adopts an advanced synchronous control module to ensure that the two folding arm cranes can work together during the lifting process to maintain the balance and stability of the steel box girder. When the PSD position sensor 4 detects that the inclination of the steel box girder exceeds the preset threshold, the control processing module will automatically adjust the operating parameters of the two folding arm machines by adjusting the control parameters of the synchronous control module to correct the inclination. The synchronous control module should adopt closed-loop control, provide real-time feedback on the operating status of the two cranes, and automatically adjust the operating parameters as needed. The PSD position sensor 4 in the present invention should have high precision and high reliability, and be able to monitor the inclination angle and inclination direction of the steel box girder in real time.

[0036] In addition, before lifting, the tipping radius 34 of the knuckle boom crane should be accurately calculated and verified to see if it meets safety requirements. The safety boundary 101 of the existing railway should be equipped with corresponding limit devices and warning signs.

[0037] During the hoisting process, the load rate of the hoisting (steel box girder weight G box / crane rated lifting weight G rated) is monitored in real time to ensure that it is controlled within 70%. This helps to improve the safety reserve of the hoisting process and reduce the risk of accidents.

[0038] A guy rope 7 is arranged on the upper part of the main arm and is firmly fixed to the ground through a ground anchor 72. The arrangement of the guy rope 7 should ensure that the main arm can be provided with stable support and restraint during the hoisting process. The guy rope 7 should be made of a material with sufficient strength and flexibility to ensure that it can withstand the maximum load during the operation of the folding arm crane. The anchoring point of the guy rope 7 should be selected on a solid and reliable foundation, and an appropriate anchoring method should be adopted. The guy rope 7 can be tightened at any time by a hand winch 71 to adjust its supporting force on the main arm. This helps to maintain the stability and safety of the main arm during the hoisting process. The guy rope 7 is connected to the anti-overturning self-locking device 9 to ensure that the main arm can be quickly locked in an unexpected situation to prevent it from overturning; the anti-overturning self-locking device 9 can adopt an existing speed differential anti-fall device. At the same time, combined with the damping device 8, the influence of unexpected impact loads on the guy rope 7 can be reduced, thereby reducing the influence on the folding arm crane and the steel box girder. The anti-overturning self-locking device 9 should have a sensitive and reliable trigger mechanism, which can quickly lock the main arm in an emergency. The damping device 8 should be able to effectively absorb the impact energy and reduce the damage to the knuckle boom crane and steel box girder in unexpected situations.

[0039] Those skilled in the art should understand that those skilled in the art can implement variations by combining the prior art and the above embodiments, which will not be described in detail here. Such variations do not affect the essential content of the present invention, and will not be described in detail here.

[0040] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

Claims

1. A steel box girder lifting system under space-constrained conditions, used to lift the steel box girder to a supporting structure, the supporting structure is adjacent to an existing railway, and a viaduct is arranged above the supporting structure, characterized in that: The lifting system includes: two folding arm cranes and a control system; The two folding arm cranes are respectively located on both sides of the supporting structure, and the overturning track of any one of the folding arm cranes is located outside the safety limit of the existing railway, and the operating radius of any one of the folding arm cranes at the lifting position and the in-position position of the steel box girder is smaller than the maximum operating radius of the folding arm crane; A distance sensor is provided at the top of the main arm of each folding arm crane, and the distance sensor is used to monitor the distance between the top of the main arm of the folding arm crane and the bottom surface of the viaduct in real time; two folding arm crane lifting points are provided at the top of the steel box girder, and a PSD position sensor is provided near the top of the steel box girder and each of the folding arm crane lifting points, and sound and light alarms are provided on the distance sensor and the PSD position sensor; The control system includes a synchronous control module and a control processing module. The synchronous control modules are respectively connected to the two folding arm cranes to control the two folding arm cranes to work together during the steel box girder hoisting process. The control processing module is respectively connected to the synchronous control module, the distance sensor, the PSD position sensor and the sound and light alarm to adjust the control parameters of the synchronous control module according to the detection data of the distance sensor and the PSD position sensor, and control the sound and light alarm located on the distance sensor to alarm when the distance detected by the distance sensor is less than a preset safety value, and control the sound and light alarm located on the PSD position sensor to alarm when the difference between the data detected by the two PSD position sensors is greater than a preset threshold.

2. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: A guy rope is connected between the upper part of the main arm of each folding arm crane and the ground, and the guy rope and the existing railway are respectively located on two opposite sides of the folding arm crane.

3. The steel box girder lifting system under space-constrained conditions as claimed in claim 2, characterized in that: The guy rope is anchored on the ground.

4. The steel box girder lifting system under space-constrained conditions as claimed in claim 2, characterized in that: A hand chain hoist is arranged on the guy rope, so as to tighten the tightness of the guy rope through the hand chain hoist.

5. The steel box girder lifting system under space-constrained conditions as claimed in claim 2, characterized in that: The guy rope is provided with a damping device and an anti-overturning self-locking device.

6. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: The preset safety value is 0.5m.

7. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: The preset threshold is 0.2m.

8. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: The distance between the overturning track of the folding crane and the safety limit of the existing railway is greater than 1.5m.

9. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: The load factors of the two folding arm cranes are both lower than 70%.

10. The steel box girder lifting system under space-constrained conditions as claimed in claim 1, characterized in that: It is characterized in that The supporting structure is a supporting tower or a bridge pier.

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