Method for correcting construction quality defects of large-span heavy-load steel structure truss

Abstract

The invention relates to the technical field of truss deviation rectification, in particular to a large-span heavy-load steel structure truss construction quality defect deviation rectification method. Comprising the following steps: S1, cleaning a load on a truss to be rectified; s2, the horizontal truss offset distance of the truss to be corrected is measured; s3, the weight of the truss to be corrected is calculated, and a traction part is installed on the horizontal truss; passive traction parts are mounted on the outer sides of two vertical trusses of the truss to be rectified; monitoring points used for detecting the displacement distance of the to-be-rectified truss in the horizontal direction and the vertical direction are installed on the to-be-rectified truss; s4, controlling the traction part to work according to the weight of the truss to be rectified; s5, adjusting the working mode of the traction part according to the data detected by the monitoring points; and S6, the deviation recovery part of the truss to be subjected to deviation correction is reinforced. The method is ingenious in design and easy to implement, the truss to be corrected does not need to be dismantled, the construction cost is reduced, and the construction efficiency of truss correction is improved.

Description

Technical Field

[0001] The invention relates to the technical field of truss correction, and in particular to a method for correcting construction quality defects of a large-span heavy-load steel structure truss. Background Art

[0002] The main body of the mine ventilation heat extraction chamber of Dongzhou Kiln Coal is generally a large-span steel truss support structure. The truss rods are generally processed in the processing plant and assembled on site. The support columns of the large-span steel structure truss are in the form of steel frames, and the upper structure of the steel structure truss structure is a portal steel structure with a plane size of 44×24.5m, an eaves height of 41.93m, and 10 floors. During the construction of the main structure, due to many reasons such as construction procedures and construction management errors, the large-span steel structure truss produced vertical deformation displacement, and the steel structure frame support column produced horizontal deformation displacement. Serious quality defects directly affected the installation and safe use of the equipment. The existing correction method generally adopts overall disassembly, replacing the deformed parts and reinstalling them. This is not only costly, but also time-consuming and labor-intensive. Therefore, it is urgent to solve it.

[0003] The above contents are only used to assist in understanding the technical solution of the present invention, and do not constitute an admission that the above contents are the closest prior art. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for correcting construction quality defects of large-span and heavy-load steel structure trusses. The method is cleverly designed, easy to implement, and does not require dismantling of the trusses to be corrected, thereby reducing construction costs and improving the construction efficiency of truss correction.

[0005] To achieve the above object, the technical solution of the present invention is implemented as follows: a method for correcting construction quality defects of a large-span heavy-load steel structure truss, comprising the following steps:

[0006] S1. Clear the load on the truss to be corrected;

[0007] S2, measuring the offset distance of the truss to be corrected in the horizontal direction and the vertical direction;

[0008] S3. Calculate the weight of the truss to be corrected, and install a traction part on the horizontal truss to adjust the offset distance of the truss to be corrected in the horizontal direction and the vertical direction; install a passive traction part on the outer side of the two vertical trusses of the truss to be corrected to offset the traction force generated by the traction part on the vertical truss; install a monitoring point on the truss to be corrected to detect the displacement distance of the truss to be corrected in the horizontal direction and the vertical direction;

[0009] S4, according to the weight of the truss to be corrected, controlling the traction part to apply a first upward traction force on the top of the horizontal truss, and the passive traction part to apply a second traction force on the outer sides of the two vertical trusses of the truss to be corrected to offset the traction of the vertical trusses by the first traction force;

[0010] S5. According to the data detected at the monitoring point, the magnitude of the first traction force applied by the traction part and the working time of the traction part are adjusted until the offset part of the truss to be corrected is completely reset;

[0011] S6. Reinforce the parts where the deviation of the truss needs to be restored.

[0012] Preferably, the traction part in step S3 includes: a steel cable, a support frame and a jack; the steel cable is arranged below the horizontal truss, and the two ends of the steel cable are respectively connected to the top ends of the two vertical trusses; one end of the support frame is vertically connected to the bottom of the horizontal truss, and the other end abuts against the middle of the steel cable; the jack is fixed on the upper surface of the horizontal truss and is located at the connection between the horizontal truss and the vertical truss, and is used to push the vertical truss.

[0013] Preferably, it further comprises a crane for assisting traction; the crane applies an upward traction force to the horizontal truss.

[0014] Preferably, the passive traction part includes a first steel cable, a first ground anchor, a second steel cable and a second ground anchor; the first ground anchor and the second ground anchor are respectively buried in the ground outside two vertical trusses; one end of the first steel cable is connected to the top of a vertical truss, and the other end of the first steel cable is connected to the first ground anchor; one end of the second steel cable is connected to the top of another vertical truss, and the other end of the second steel cable is connected to the second ground anchor.

[0015] Preferably, the connection point between the first steel cable and the vertical truss and the connection point between the second steel cable and another vertical truss respectively coincide with the connection points between the steel cable and the two vertical trusses.

[0016] Preferably, the support frame includes a vertical rod, an inclined rod and a fixed pulley; one end of the vertical rod is vertically connected to the middle of the lower surface of the horizontal truss, and the other end of the vertical rod is connected to the fixed pulley; there are two inclined rods, which are respectively arranged on both sides of the vertical rod, and one end of the vertical rod is connected to the middle of the vertical rod, and the other end is connected to the lower surface of the horizontal truss.

[0017] Preferably, there are at least two groups of support frames and steel cables, and adjacent support frames are connected by connecting rods.

[0018] Preferably, pulley blocks are provided at the connection between the first steel cable and the first ground anchor and at the connection between the second steel cable and the second ground anchor.

[0019] Preferably, dynamometers are provided at the connections between the first steel cable and the second steel cable and the pulley block.

[0020] The beneficial effects of the present invention are embodied in:

[0021] The present invention corrects the deviation by reversely tensioning the truss to be corrected with steel cables and balancing it with ground anchors, and at the same time uses a crane-assisted lifting method to correct the deviation. Not only can it achieve automatic resetting without changing the overall stress of the truss to be corrected and achieve a safe and efficient correction effect, but the application and practice of this method also have high academic promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the present invention showing the truss to be corrected for deviation.

[0023] Figure 2 It is a schematic diagram of the structure of the traction part of the present invention;

[0024] Figure 3 It is a schematic diagram of the support frame structure of the present invention;

[0025] Figure 4 It is a structural schematic diagram of the jack installation part of the present invention.

[0026] Description of reference numerals:

[0027] a1, horizontal truss; a2, vertical truss; 10, steel cable; 20, support frame; 21, vertical rod; 22, tilt rod; 23, fixed pulley; 30, jack; 41, first steel cable; 411, first anchor; 42, second steel cable; 421, second anchor. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] See also Figure 1-4 As shown:

[0031] The present invention provides a method for correcting construction quality defects of a large-span heavy-load steel structure truss, comprising the following steps:

[0032] S1. Clear the load on the truss to be corrected.

[0033] The load is generally a cast reinforced concrete composite floor slab, and the unloading target is achieved by removing the concrete load of the cast reinforced concrete composite floor slab. After clearing and unloading the load, the large-span steel structure trusses and steel frame columns of the trusses to be corrected can restore some elastic deformation, that is, the horizontal truss a1 and the vertical truss a2 can restore some elastic deformation, but it still does not reach the limit specified in the specification, and further correction is required.

[0034] S2. Measure the horizontal and vertical offset distances of the truss to be corrected.

[0035] In specific applications, what is mainly measured is the horizontal displacement distance of the horizontal truss a1 and the horizontal displacement distance of the vertical truss a2.

[0036] S3. Calculate the weight of the truss to be corrected, and install a traction part on the horizontal truss a1 to adjust the offset distance of the horizontal truss a1 in the horizontal direction and the vertical direction. Apply a passive traction part on the outer side of the two vertical trusses a2 of the truss to be corrected to offset the traction force generated by the traction part on the vertical truss a2. Install monitoring points on the truss to be corrected to detect the displacement distance of the truss to be corrected in the horizontal direction and the vertical direction.

[0037] According to the weight of the truss to be corrected, a suitable traction part is selected to ensure that there is sufficient power to reset the offset part of the truss to be corrected. Setting monitoring points can ensure that when the traction part is working, the operator can grasp the reset status of the offset part of the truss to be corrected in real time.

[0038] S4. According to the weight of the truss to be corrected, the traction part is controlled to apply a first upward traction force on the top of the horizontal truss a1, and the passive traction part applies a second traction force on the outer sides of the two vertical trusses a2 of the truss to be corrected to offset the traction of the first traction force on the vertical truss a2.

[0039] Through the mutual cooperation between the traction part and the passive traction part, when the traction part drives the upper end surface of the horizontal truss a1 to move upward, the passive traction part can offset the upward pulling force transmitted to the vertical truss a2 by the traction part through the horizontal truss a1. At the same time, when the lower end surface of the horizontal truss a1 moves upward, the passive traction part can offset the pulling force in the horizontal direction on the vertical trusses a2 on both sides caused by the deformation of the lower surface of the horizontal truss a1.

[0040] S5. According to the data detected at the monitoring point, the magnitude of the first traction force applied by the traction part and the working time of the traction part are adjusted until the offset part of the truss to be corrected is completely reset.

[0041] By changing the traction force and traction time, the correction of the truss to be corrected is carried out step by step, and the entire correction construction is more in line with the deformation law of the truss to be corrected. This makes the overall structural deformation process more stable and the reset effect better when the truss to be corrected recovers the horizontal and vertical deviations under the action of external force.

[0042] S6. Reinforce the parts where the deviation of the truss needs to be restored.

[0043] The traction part is mainly composed of a steel cable 10 , a support frame 20 and a jack 30 .

[0044] The steel cable 10 is disposed below the horizontal truss a1, and the two ends of the steel cable 10 are respectively connected to the top ends of the two vertical trusses a2. One end of the support frame 20 is vertically connected to the bottom of the horizontal truss a1, and the other end is abutted against the middle of the steel cable 10.

[0045] The support frame 20 includes a vertical rod 21, an inclined rod 22 and a fixed pulley 23. One end of the vertical rod 21 is vertically connected to the middle of the lower surface of the horizontal truss a1, and the other end of the vertical rod 21 is connected to the fixed pulley 23. The fixed pulley 23 is connected to the middle of the steel cable 10. There are two inclined rods 22, which are respectively arranged on both sides of the vertical rod 21, and one end of the vertical rod 21 is connected to the middle of the vertical rod 21, and the other end is connected to the lower surface of the horizontal truss a1.

[0046] The support frame 20 is provided to form a stable support in the middle of the horizontal truss a1, so that the steel cable 10 can be pushed stably along the bottom of the horizontal truss a1 when being tensioned.

[0047] The jack 30 is fixed on the upper surface of the horizontal truss a1 and is located at the connection between the horizontal truss a1 and the vertical truss a2, and is used to push the vertical truss a2.

[0048] In specific application, a fixed block is set on the vertical truss a2, and the telescopic end of the jack 30 pushes the fixed block, thereby pushing the vertical truss a2 to deform and move in the horizontal direction. The two ends of the steel cable 10 are respectively connected to the top of the vertical truss a2, so that when the jack 30 pushes the vertical truss a2, the steel cable 10 is tensioned, thereby driving the support frame 20 to push the horizontal truss a1 from the bottom of the horizontal truss a1, thereby driving the horizontal truss a1 to move in the vertical direction.

[0049] In this way, the horizontal and vertical deviations of the trusses to be corrected can be corrected easily, which is simple and efficient.

[0050] A crane for auxiliary traction is also included; the crane applies an upward traction force to the horizontal truss a1.

[0051] When the horizontal deviation of the vertical truss a2 has been corrected and completely restored, and the vertical deviation of the horizontal truss a1 is still not completely restored, an upward traction force is applied to the horizontal truss a1 with the help of an auxiliary traction crane until the horizontal truss a1 is completely restored.

[0052] The passive traction part is mainly composed of a first steel cable 41, a first anchor 411, a second steel cable 42 and a second anchor 421. The first anchor 411 and the second anchor 421 are respectively buried in the ground outside the two vertical trusses a2; generally, before the deviation-correcting truss is pulled, the first anchor 411 and the second anchor 421 formed by pouring concrete are installed first, and when the concrete is completely solidified and meets the construction standard, the deviation-correcting truss is pulled and reset.

[0053] In specific application, one end of the first steel cable 41 is connected to the top of a vertical truss a2, and the other end of the first steel cable 41 is connected to the first anchor 411. One end of the second steel cable 42 is connected to the top of another vertical truss a2, and the other end of the second steel cable 42 is connected to the second anchor 421.

[0054] In order to concentrate the stress points more when the steel cable 10 is tensioned, the connection between the first steel cable 41 and the vertical truss a2 and the connection between the second steel cable 42 and another vertical truss a2 are overlapped with the connection between the steel cable 10 and the two vertical trusses a2 respectively.

[0055] In addition, in order to ensure that the ends of the first steel cable 41, the second steel cable 42 and the steel cable 10 are not easily detached from the connection points with the vertical truss a2 during the tensioning process, connection bases are used at the connection points for reinforcement.

[0056] When the single truss in the horizontal truss a1 is tensioned, there are at least two groups of support frames 20 and steel cables 10, and adjacent support frames 20 are connected by connecting rods, so that the force is more balanced when the single truss is corrected.

[0057] Pulley blocks are provided at the connection between the first steel cable 41 and the first ground anchor 411, and at the connection between the second steel cable 42 and the second ground anchor 421. The lengths of the first steel cable 41 and the second steel cable 42 are adjusted by the pulley blocks to ensure that the horizontal and vertical forces acting on the vertical truss a2 can be offset by the tension provided by the first steel cable 41 and the second steel cable 42, thereby achieving a force balance state.

[0058] The connection between the first steel cable 41 and the second steel cable 42 and the pulley block is provided with a dynamometer, which can effectively monitor the horizontal force during the tensioning of the steel cable 10 and ensure that the horizontal force of the steel cable 10 during the tensioning process does not cause the vertical truss a2 to continue to move inward horizontally.

[0059] Example 2

[0060] Steps S5 and S6 are specifically implemented as follows:

[0061] When the vertical deviation of a single truss in the horizontal truss a1 of the trusses to be corrected is relatively large, the tensioning operation of the steel cable 10 starts with the single truss with the largest vertical deviation, and then the tensioning of other trusses is performed.

[0062] After all the single-piece trusses are tensioned, all the single-piece trusses are measured, and the single-piece trusses that still do not meet the standards are further tensioned using steel cables 10.

[0063] In addition, the single truss in the horizontal truss a1 is tensioned in steps, and the interval time between step loading is 10 minutes. The step tension values ​​are shown in the following table: Step tension values

[0064]

[0065] In addition, when the tensioning force of the steel cable 10 is 100% of the total value, the verticality of the vertical truss a2 is measured; if it meets the design requirements, the tensioning is stopped, and if it does not meet the requirements, super tensioning is performed.

[0066] If the super-tensioning load is 115%, if the verticality of the vertical truss a2 still exceeds the design requirements, a crane is used to assist in lifting.

[0067] The lifting capacity of the crane should be determined by calculation based on the working range and the length of the crane arm, and the lifting force of the crane should be controlled within 50% of the rated lifting capacity.

[0068] The double control principle is adopted during tensioning: the cable force and deformation of the steel cable 10 are controlled, and the deformation control is mainly used. If the design value of the applied prestress is not in place, the tensioning is stopped when the structural deformation and stress value of the deviation-correcting truss exceed the design value.

[0069] During the tensioning process, by adjusting the tension of the pulley block on the first steel cable 41 and the second steel cable 42, always pay attention to the tension value of the dynamometer to ensure that the horizontal tension value of the first steel cable 41 and the second steel cable 42 is not less than the horizontal tension value of the steel cable 10.

[0070] After the steel cable 10 is tensioned, the steel cable 10 is not removed temporarily, and the first anchor 411 and the second anchor 421 are protected.

[0071] After the displacement of all the single-piece trusses in the horizontal truss a1 in the vertical direction is restored, if the horizontal displacement of the vertical truss a2 exceeds the design requirement, the tension of the first steel cable 41 and the second steel cable 42 should be used to continue to correct the deviation of the vertical truss a2.

[0072] Strengthening of the steel trusses to be corrected: After the horizontal truss a1 and the vertical truss a2 are completely corrected, that is, after the displacement is restored, welding of the truss bolt nodes is carried out; whether the structural members are strengthened with rods refers to the design changes.

[0073] In addition, the splicing nodes of the steel trusses to be corrected after resetting are welded to meet the design requirements; whether the structural members are reinforced with rods, see the design changes.

[0074] After the steel structure is strengthened, the cables and wire ropes are removed.

[0075] Example 3

[0076] The setting of the monitoring points in step S3 is as follows;

[0077] One monitoring point is set in the single truss of the horizontal truss a1, and the monitoring point is set in the middle of the span.

[0078] One monitoring point is set on the vertical truss a2, and the monitoring point is set on the side of the column at the top of the upper chord of the vertical truss a2.

[0079] Monitoring method

[0080] 1) Weld the vertical steel bars at the midpoint of the upper chord of the truss and mark the bars with scale.

[0081] 2) Set the observation reference point, align the level with the reference point, set the reading, rotate the level, observe the steel bar scale on the truss, and calculate the verticality of the truss.

[0082] 3) Weld horizontal steel bars on the column and tie a plumb bob to the horizontal steel bars. Measure the horizontal distance above and below the measuring point and calculate the horizontal offset of the column.

[0083] 4) The steel cables should be tensioned in 10 steps and the amount of truss settlement should be recorded at each time.

[0084] 5) The tensioning provided by the first steel cable 41, the first anchor 411, the second steel cable 42 and the second anchor 421 is performed synchronously with the steel cable 10, and when necessary, it is ensured that the horizontal force provided by the first steel cable 41 and the second steel cable 42 is greater than the horizontal force of the steel cable 10.

[0085] Monitoring frequency

[0086] 1) Before the truss to be corrected is stretched, measure once as the original data. Then measure once each time it is stretched.

[0087] 2) Measure once before the concrete of the floor slab is removed as the original data, and measure once after the concrete is removed.

[0088] 3) When calibrating the column, measure again, and measure once every time the load increases by 20%.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for correcting construction quality defects of large-span and heavy-load steel structure trusses, characterized in that: The following steps are involved: S1. Clear the load on the truss to be corrected; S2, measuring the offset distance of the truss to be corrected in the horizontal direction and the vertical direction; S3, calculate the weight of the truss to be corrected, and install a traction part on the horizontal truss (a1) for adjusting the offset distance of the truss to be corrected in the horizontal direction and the vertical direction; install a passive traction part on the outer side of the two vertical trusses (a2) of the truss to be corrected that can offset the traction force generated by the traction part on the vertical truss (a2); install a monitoring point on the truss to be corrected for detecting the displacement distance of the truss to be corrected in the horizontal direction and the vertical direction; S4, according to the weight of the truss to be corrected, the traction part is controlled to apply a first upward traction force on the top of the horizontal truss (a1), and the passive traction part is controlled to apply a second traction force on the outer sides of the two vertical trusses (a2) of the truss to be corrected to offset the traction of the first traction force on the vertical trusses (a2); S5. According to the data detected at the monitoring point, the magnitude of the first traction force applied by the traction part and the working time of the traction part are adjusted until the offset part of the truss to be corrected is completely reset; S6. Reinforce the parts where the deviation of the truss needs to be restored.

2. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 1, characterized in that: The traction part in step S3 includes: a steel cable (10), a support frame (20) and a jack (30); the steel cable (10) is arranged below the horizontal truss (a1), and the two ends of the steel cable (10) are respectively connected to the top ends of the two vertical trusses (a2); one end of the support frame (20) is vertically connected to the bottom of the horizontal truss (a1), and the other end is abutted against the middle of the steel cable (10); the jack (30) is fixed on the upper surface of the horizontal truss (a1) and is located at the connection between the horizontal truss (a1) and the vertical truss (a2), and is used to push the vertical truss (a2).

3. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 2, characterized in that: It also includes a crane for auxiliary traction; the crane applies an upward traction force to the horizontal truss (a1).

4. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 2 or 3, characterized in that: The passive traction part comprises a first steel cable (41), a first ground anchor (411), a second steel cable (42) and a second ground anchor (421); the first ground anchor (411) and the second ground anchor (421) are respectively buried in the ground outside two vertical trusses (a2); one end of the first steel cable (41) is connected to the top of one vertical truss (a2), and the other end of the first steel cable (41) is connected to the first ground anchor (411); one end of the second steel cable (42) is connected to the top of another vertical truss (a2), and the other end of the second steel cable (42) is connected to the second ground anchor (421).

5. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 4, characterized in that: The connection point between the first steel cable (41) and the vertical truss (a2) and the connection point between the second steel cable (42) and another vertical truss (a2) respectively coincide with the connection points between the steel cable (10) and the two vertical trusses (a2).

6. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 5, characterized in that: The support frame (20) comprises a vertical rod (21), an inclined rod (22) and a fixed pulley (23); one end of the vertical rod (21) is vertically connected to the middle of the lower surface of the horizontal truss (a1), and the other end of the vertical rod (21) is connected to the fixed pulley (23); there are two inclined rods (22), which are respectively arranged on both sides of the vertical rod (21), and one end of the vertical rod (21) is connected to the middle of the vertical rod (21), and the other end is connected to the lower surface of the horizontal truss (a1).

7. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 6, characterized in that: There are at least two groups of support frames (20) and steel cables (10), and adjacent support frames (20) are connected via connecting rods.

8. A method for correcting construction quality defects of a large-span, heavy-load steel structure truss according to claim 6, characterized in that: A pulley block is provided at the connection point between the first steel cable (41) and the first ground anchor (411) and at the connection point between the second steel cable (42) and the second ground anchor (421).

9. The cleaning method for correcting construction quality defects of a large-span heavy-load steel structure truss according to claim 7 is characterized in that: A dynamometer is provided at the connection between the first steel cable (41) and the second steel cable (42) and the pulley block.

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