Concrete prefabricated T beam erecting method capable of avoiding stress concentration in hoisting process

Abstract

The invention discloses a concrete prefabricated T beam erection method capable of avoiding stress concentration in a hoisting process, which relates to the technical field of concrete prefabricated T beam erection and comprises the steps of hoisting equipment synchronism control, dynamic load control, defect detection and treatment in a prefabrication stage, hoisting point arrangement optimization and beam body fixation and protection. Through synchronous control, dynamic load control and defect detection and treatment in the prefabrication stage of the hoisting equipment, and optimization of hoisting point arrangement and fixation and protection of the beam body, the problem of stress concentration caused by various factors during hoisting of the concrete prefabricated T-beam in the prior art can be effectively solved, structural damage such as distortion and cracks of the beam body is avoided, and the construction quality of the concrete prefabricated T-beam is improved. The structure integrity and safety of the beam body are improved, the quality of bridge engineering is ensured, and due to the fact that the beam body is evenly stressed in the hoisting process, sudden structural damage caused by stress concentration is avoided, so that the safety risk in the construction process is greatly reduced, and the life safety of constructors and the smooth proceeding of the engineering are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete prefabricated T-beam erection, in particular to a concrete prefabricated T-beam erection method capable of avoiding stress concentration in the hoisting process. BACKGROUND

[0002] In modern bridge construction, prefabricated components have become the mainstream choice due to advantages such as standardized production and controllable quality, and the concrete prefabricated T-beam, as the core load-bearing structure, is named for its T-shaped cross-section (composed of a beam rib and a flange plate). After being prefabricated and cured in a factory, it is transported to the site for erection, can efficiently bear the self-weight of the bridge superstructure and vehicle loads, has the characteristics of large bending stiffness and high material utilization rate, and is a commonly used component for small and medium span bridges, which is usually installed and fixed by hoisting.

[0003] However, in the prior art, the hoisting equipment has poor synchronicity during the hoisting of the concrete prefabricated T-beam, which can cause the beam body to twist due to unbalanced stress at each hoisting point, resulting in additional stress on the weak part and causing structural damage. The dynamic load is out of control during the operation process, whether it is sudden stopping and starting during lifting, sudden turning during translation, or "hard landing" during beam landing, which can cause the beam body to bear impact far beyond the normal range, causing local stress to exceed the limit and weakening the structural bearing capacity. The defects existing in the prefabrication stage are ignored, which provides a breakthrough for stress concentration for the first two types of problems, causing the originally bearable load to suddenly damage the structure at this point, and such damage is hidden, which may suddenly fail in subsequent operations, greatly increasing the safety hazard;

[0004] Permanent damage to the beam body structure not only requires a large amount of resources for repair, but also leaves durability hazards and shortens its service life; the construction safety risk increases sharply, which may cause accidents and cause incalculable losses; the project progress is also delayed, which has a chain reaction, affecting the overall construction period and increasing various costs. SUMMARY

[0005] The purpose of the present application is to provide a concrete prefabricated T-beam erection method capable of avoiding stress concentration in the hoisting process to solve the problems raised in the background.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a concrete prefabricated T-beam erection method capable of avoiding stress concentration in the hoisting process, S1, hoisting equipment synchronicity control: a high-precision synchronous control system is installed on the hoisting equipment, the position, speed and stress of each hoisting point are monitored in real time by a sensor and transmitted to a central processor, the central processor accurately controls the action of each hoisting point according to the preset synchronization parameters, and the equipment is comprehensively checked and maintained before each hoisting operation.

[0007] S2, dynamic load control: an intelligent hoisting operation control system is adopted to monitor and analyze parameters such as acceleration, speed and displacement in real time during hoisting, to predict dynamic load in combination with beam parameters and to optimize control of hoisting equipment operation, and a buffer device composed of elastic elements such as rubber pads and springs is arranged between the hoisting equipment and the beam;

[0008] S3, defect detection and treatment in the prefabrication stage: before the prefabricated T-beam is delivered, non-destructive testing technologies such as ultrasonic testing and radar testing are used to comprehensively detect defects in the beam, and for the detected defects, corresponding measures such as pressure grouting and local cutting repair are used for treatment according to the type and severity;

[0009] S4, optimization of lifting point setting: according to the structural characteristics, size parameters and weight distribution of the concrete prefabricated T-beam, the optimal lifting point position and number are determined by using finite element analysis software; a lifting point reinforcing structure composed of reinforcing elements such as steel plates and steel bars is arranged at the determined lifting point position.

[0010] S5, fixation and protection of the beam: before hoisting, an adjustable clamp is used to firmly connect the beam and the hoisting equipment; a protective pad made of rubber and nylon flexible material is arranged at the contact part of the beam and the hoisting equipment and at the stress concentration part.

[0011] Preferably, the sensors of the high-precision synchronous control system include position sensors, speed sensors and pressure sensors, which are respectively used to monitor the position, speed and stress of each lifting point in real time.

[0012] Preferably, the algorithm used by the intelligent hoisting operation control system includes a dynamic load prediction algorithm based on neural network and an adaptive control algorithm to realize accurate optimization of the hoisting equipment operation.

[0013] Preferably, the ultrasonic testing in the non-destructive testing technology uses a multi-channel ultrasonic testing instrument, which can simultaneously detect multiple parts of the beam.

[0014] Preferably, the thickness of the steel plate in the lifting point reinforcing structure is 8-15mm, and the steel plate and the beam are connected by welding, and the welding length is not less than 2 / 3 of the circumference of the steel plate.

[0015] Preferably, the adjustable clamp includes two symmetrically arranged clamping arms, the inner side of the clamping arm is provided with a non-slip pad layer, and the clamping arms are opened and closed by a hydraulic driving device, and the adjustment range is adapted to different sizes of concrete prefabricated T-beams.

[0016] Preferably, the thickness of the protective pad is 20-50mm, and the surface of the protective pad in contact with the beam is provided with concave-convex texture.

[0017] Preferably, in the hoisting equipment synchronism control, the preset synchronism parameters include that the position deviation of each hoisting point is not more than ±5mm, the speed deviation is not more than ±0.05m / s, and the stress deviation is not more than 5% of the design value.

[0018] Preferably, in the dynamic load control, the acceleration in the hoisting stage is not more than 0.5m / s², the steering angular velocity in the translation stage is not more than 0.1rad / s, and the impact coefficient in the beam falling stage is controlled within 1.2.

[0019] Preferably, in the defect detection and treatment in the prefabrication stage, the grouting material used in the pressure grouting is an epoxy resin modified cement slurry, and the compressive strength is not less than 1.2 times of the design strength of the beam body concrete.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] 1. In the present application, through the hoisting equipment synchronism control, the dynamic load control, the defect detection and treatment in the prefabrication stage, the optimization of the hoisting point setting and the fixation and protection of the beam body, the stress concentration problem caused by various factors during the hoisting of the concrete prefabricated T-beam in the prior art can be effectively solved, the structural damage such as distortion and crack of the beam body is avoided, the structural integrity and safety of the beam body are improved, the quality of the bridge engineering is ensured, since the stress of the beam body is uniform during the hoisting process, the sudden structural damage caused by stress concentration is avoided, thereby the safety risk in the construction process is greatly reduced, the probability of safety accidents is reduced, the life safety of the construction personnel and the smooth progress of the engineering are ensured.

[0022] 2. In the present application, through avoiding the large repair cost required after the structural damage of the beam body and the additional cost caused by the engineering delay, through improving the service life of the beam body, the maintenance and replacement cost of the bridge in the subsequent use process is reduced, the engineering cost is saved as a whole, through optimizing the operation control of the hoisting equipment and adopting the advanced detection and treatment technology, the hoisting operation time can be shortened, the rework times caused by quality problems can be reduced, thereby the engineering construction efficiency is improved, and the construction progress of the bridge engineering is accelerated. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The construction flowchart of the present application is a hoisting process avoiding stress concentration concrete prefabricated T-beam erection method;

[0024] Figure 2 The step flowchart of the present application is a hoisting process avoiding stress concentration concrete prefabricated T-beam erection method. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of the present application.

[0026] The present application will be further described below with reference to the embodiments.

[0027] Embodiment one: please refer to Figure 1 and Figure 2 A concrete precast T-beam erection method avoiding stress concentration in hoisting process is shown in

[0028] S1, hoisting equipment synchronism control: a high-precision synchronous control system is installed on the hoisting equipment. The system monitors the position, speed and stress of each lifting point in real time through sensors, and transmits the data to the central processor. The central processor accurately controls the lifting, lowering and translation of each lifting point according to the preset synchronization parameters, ensures that each lifting point always maintains synchronization during hoisting, makes the beam body bear uniform stress, and avoids beam body distortion and stress concentration caused by unbalanced stress of lifting points. For example, when the lifting speed of a certain lifting point is slightly faster than that of other lifting points, the synchronous control system will automatically issue instructions to reduce the lifting speed of the lifting point until the lifting speeds of all lifting points are consistent.

[0029] Select hoisting equipment with good synchronization performance, such as using cranes of the same brand, same model and strictly debugged and calibrated as hoisting equipment to ensure the synchronization of hoisting equipment from the hardware level. At the same time, before each hoisting operation, the hoisting equipment is comprehensively inspected and maintained to ensure that the performance indicators of the equipment are in good condition and reduce the synchronization problems caused by equipment failure.

[0030] S2, dynamic load control: an intelligent hoisting operation control system is used. The system monitors and analyzes the acceleration, speed and displacement parameters in the hoisting process in real time, combines with the weight, size and other parameters of the beam body, uses advanced algorithms to predict the dynamic load that the beam body may bear in different operation stages, and optimizes the control of the hoisting equipment operation according to the prediction results. For example, in the lifting stage, the system will control the crane to accelerate slowly to avoid sudden stop and start; in the translation stage, the steering speed is accurately controlled to prevent sudden steering; in the beam landing stage, the buffer device and accurate speed control are used to realize the smooth landing of the beam body and avoid the "hard landing" phenomenon, thereby effectively reducing the dynamic load borne by the beam body and reducing the risk of stress concentration.

[0031] A buffer device is arranged between the lifting equipment and the beam body, such as a buffer structure composed of elastic elements such as rubber pads and springs. When the beam body is subjected to dynamic load impact, the buffer device can absorb and disperse part of the energy, reduce the direct effect of the dynamic load on the beam body, and reduce the degree of local stress concentration of the beam body. For example, rubber buffer pads are installed at the connection between the lifting cable and the beam body. During lifting and beam lowering, the rubber pads can effectively buffer the energy generated by changes in speed and impact, protecting the beam body from damage.

[0032] S3, defect detection and processing in the prefabrication stage: Before the prefabricated T-beam is shipped, advanced non-destructive testing techniques such as ultrasonic testing and radar testing are used to conduct comprehensive defect detection on the beam body, accurately identifying whether there are defects such as concrete voids, cracks, and steel corrosion inside the beam body, as well as the location, size, and severity of the defects. For example, ultrasonic testing technology is used to scan the beam body. By analyzing the propagation speed and reflection signals of ultrasonic waves in the beam body, it can accurately determine whether there are defects inside the beam body and the specific location of the defects.

[0033] For detected defects in the prefabrication stage, appropriate measures are taken according to the type and severity of the defects. For smaller concrete voids and cracks, pressure grouting is used for repair, high-strength grouting material is injected into the defect site to fill the voids and cracks, and the integrity of the beam body is restored; for more serious defects such as large areas of loose concrete and severe steel corrosion, the defect site is partially removed and repaired, the concrete is recast and the steel reinforcement is arranged to ensure that the beam body does not have defects that affect the structural safety before lifting, eliminating stress concentration hazards.

[0034] S4, optimization of lifting point setting: According to the structural characteristics, size parameters, and weight distribution of the concrete prefabricated T-beam, finite element analysis software is used to simulate and analyze different lifting point setting schemes to determine the optimal lifting point location and number, so that the beam body is evenly stressed during lifting, avoiding local stress concentration. For example, for T-beams of different spans and cross-sectional sizes, the stress distribution of the beam body under different lifting point arrangements is calculated through finite element simulation analysis, and the lifting point setting scheme that can make the stress distribution of the beam body most uniform is determined; after determining the lifting point location, a special lifting point reinforcement structure is set on the beam body, such as adding steel plates, steel bars, etc. to the lifting point to increase the bearing capacity and anti-deformation ability of the lifting point, preventing local damage and stress concentration of the beam body caused by excessive stress on the lifting point. For example, steel plates are welded to the bottom of the beam rib and the flange plate at the lifting point location to increase the local stiffness of the beam body at the lifting point, ensuring that the lifting point can safely and reliably bear the lifting load.

[0035] S5, fixing and protection of the beam body: before hoisting, the beam body is firmly connected with the hoisting equipment by using a specially designed beam body fixing device to ensure that the beam body does not sway and displace during hoisting, further ensuring that the beam body is uniformly stressed. For example, a clamp with adjustable function is used, according to the size and shape of the beam body, the clamp is adjusted to the appropriate position and clamped on the beam body, so that the beam body and the hoisting equipment become an integral whole, and jointly bear various loads during hoisting; protective pads are arranged at the contact parts of the beam body and the hoisting equipment and the parts where stress concentration may occur, such as the corners of the beam body, around the lifting points, etc., which are made of flexible materials such as rubber and nylon, to increase the contact area, disperse the concentrated force, prevent the beam body surface from being damaged and stress concentration from occurring. For example, rubber protective pads are wrapped around the flange plate corners of the beam body, and nylon pads are placed at the contact points between the hoisting rope and the beam body, effectively protecting the beam body from damage.

[0036] Through the above series of technical means, the stress concentration problem caused by various factors during hoisting of the concrete prefabricated T-beam in the prior art can be effectively solved, the structural damage such as distortion and cracking of the beam body is avoided, the structural integrity and safety of the beam body are improved, the quality of the bridge engineering is ensured, since the beam body is uniformly stressed during hoisting, sudden structural failure caused by stress concentration is avoided, thereby greatly reducing the safety risk during construction, reducing the probability of safety accidents, protecting the life safety of construction personnel and the smooth progress of the project; by avoiding the large amount of repair costs required after structural damage of the beam body and the additional costs caused by project delay, by improving the service life of the beam body, reducing the maintenance and replacement costs of the bridge in the subsequent use process, the overall engineering cost is saved, by optimizing the operation control of the hoisting equipment and using advanced detection and processing technology, the hoisting operation time can be shortened, the number of rework caused by quality problems can be reduced, thereby improving the engineering construction efficiency and accelerating the construction progress of the bridge engineering.

[0037] Embodiment two: please refer to Figure 1 As shown in the figure, before the hoisting operation of the concrete prefabricated T-beam is carried out, systematic inspection and maintenance work of all hoisting equipment involved in the operation is needed. This includes comprehensive lubrication of the mechanical parts of the equipment, checking whether the pressure of the hydraulic system is normal, ensuring that the braking system is sensitive and reliable, and at the same time, uniformly calibrating the control system parameters of each crane, so as to ensure that the equipment has good synchronous performance during operation. After completing the equipment inspection and maintenance, a high-precision synchronous control system is installed on the crane, the sensors of the system are accurately arranged at the lifting point positions, which can monitor the position change, movement speed and force borne by the lifting point in real time and accurately, and transmit these monitoring data to the central processor in real time, providing data support for subsequent synchronous control.

[0038] Before the prefabricated T-beam leaves the production site, the ultrasonic non-destructive testing technology is used to detect every beam body in all directions and without dead angle. This detection technology can penetrate into the beam body, accurately identify possible defects such as concrete voids and cracks, etc. When a small concrete void defect is detected in the beam rib of a beam, pressure grouting method is immediately used for repair. In the specific operation, the void part is first cleaned to remove the impurities and loose materials on the surface, and then the high-strength grouting material prepared in advance is injected into the void through a special grouting equipment at a suitable pressure until the void is completely filled and the grouting material is tightly combined with the beam concrete to restore the structural integrity of the beam.

[0039] According to the structural characteristics of the T-beam itself, such as the height of the beam rib, the width of the flange plate, and the specific size parameters and weight distribution, a three-dimensional model of the beam body is constructed by means of finite element analysis software, and different lifting point setting schemes are simulated and analyzed. By simulating the stress distribution state of the beam body under different numbers and positions of lifting points, the optimal lifting point setting scheme is finally determined, which is to set 4 lifting points for the beam body in this embodiment. After determining the position of the lifting point, a steel plate with appropriate thickness is welded at the lifting point as a reinforcing structure, and the welding quality is strictly controlled during the welding process to ensure that the weld is full and firm, so as to enhance the load-bearing capacity and anti-deformation capacity of the lifting point position. Before the lifting operation starts, a specially designed adjustable clamp is used to firmly connect the beam body with the lifting cable of the crane, and the adjustment range of the clamp can adapt to beams of different sizes. By adjusting the clamp tightly around the beam, it is ensured that the beam does not shake and move during the lifting process. At the same time, rubber protective pads with certain thickness and elasticity are wrapped around the corners of the beam body and the positions around the lifting points where stress concentration is easy to occur, so as to disperse the stress and avoid damage to the surface of the beam body.

[0040] After entering the lifting process, the intelligent lifting operation control system begins to play a role, which can receive and analyze the parameters of the beam body and the monitoring data of the lifting points in real time, and accurately control the operation of the crane according to the analysis results. During the lifting stage, the control system controls the crane to gradually accelerate at a slow speed, and strictly controls the lifting speed within a reasonable range to avoid excessive impact load due to too fast lifting speed. During the beam translation process, the steering speed is accurately controlled to ensure the stable movement of the beam and prevent the beam from being out of balance due to sudden steering. In the beam landing stage, the buffer device is started, and the beam lands slowly at a stable speed through the action of the buffer device, avoiding the "hard landing" phenomenon. The whole lifting process is orderly carried out under the precise control of the control system, and after completion, the beam body is subjected to comprehensive structural detection, and the results show that the beam body has no any structural damage, and all mechanical performance indicators meet the design standards and relevant specification requirements.

[0041] Example Three: Please refer to Figure 1As shown, in this bridge construction project, the same method of the present application as in Example Two is used for the hoisting operation of the prefabricated T-beams. In terms of the synchronization control of the hoisting equipment, in addition to installing a synchronization control system for the equipment and selecting the same type of crane as in Example Two, professional monitoring personnel are arranged at the construction site. These monitoring personnel have rich hoisting operation experience and professional knowledge, can observe the running state of each lifting point in real time, including whether the lifting height and movement speed of the lifting point are consistent, and once any abnormal situation is found, such as the speed of a lifting point being too fast or too slow, can timely signal the operator to make adjustments, so as to further ensure the synchronization of the hoisting equipment.

[0042] For the defect detection of the prefabricated T-beams, the radar detection technology is used in this embodiment. This technology can quickly and efficiently detect the beam body by emitting electromagnetic waves and receiving reflected signals, and is especially suitable for detecting defects on the surface and shallow layer of the beam body. During the detection process, it is found that a small amount of fine cracks exist in the flange plate of part of the beam body. For these cracks, the surface sealing method is used for treatment. First, special tools are used to thoroughly clean the surface of the cracks, removing dust, debris and loose concrete debris inside the cracks, and then the crack sealing glue is evenly applied to the surface of the cracks and a certain range around the cracks, to ensure that the sealing glue can fully penetrate into the cracks to form a tight sealing layer, prevent harmful substances such as water and air from entering the cracks, avoid further expansion of the cracks, and ensure the structural stability of the beam body.

[0043] In the optimization of the lifting point setting link, the finite element analysis software is also used to simulate and analyze the lifting point setting of T-beams of different spans according to the structural characteristics, size parameters and weight distribution of the T-beams. Through simulation calculation, the best number and position of lifting points for T-beams of different spans are determined to ensure uniform stress of the beam body during hoisting. In addition to using steel plates for reinforcement, a steel reinforcement layer is also added at the determined lifting point position, which further improves the structural strength and carrying capacity of the lifting point part by increasing the number and density of steel bars, to ensure that the lifting point can stably bear the load during hoisting.

[0044] In terms of beam body fixation and protection, a new type of beam body fixing device is used. Compared with traditional devices, this device has stronger clamping force and stability, and can better adapt to beam bodies of different sizes and shapes. High-performance protective pads are used at the parts in contact with the beam body. These protective pads have good elasticity and wear resistance, can effectively disperse the stress at the contact part, and avoid damage to the surface of the beam body caused by extrusion.

[0045] During the actual lifting operation, the operator strictly follows the instructions from the intelligent lifting operation control system. The control system monitors various parameters in real time, such as the lifting height, translation speed, and acceleration of the beam body, and dynamically adjusts the equipment according to these parameters to ensure that the dynamic load is always within a controllable range. Through a series of precise operations and controls, all T-beams safely and smoothly complete the lifting operation. After the lifting is completed, the structural performance of the beam body is detected, and the results show that the engineering quality is significantly guaranteed, and the construction efficiency is also greatly improved. Compared with the traditional lifting method, the construction period is effectively shortened, and no safety accidents occur during the entire construction process, achieving good economic and social benefits.

[0046] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions recorded in the foregoing embodiments or make equivalent replacements for part of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for erecting prefabricated concrete T-beams to avoid stress concentration during the hoisting process, characterized in that: The following steps are involved: S1. Hoisting Equipment Synchronization Control: A high-precision synchronization control system is installed on the hoisting equipment. Sensors monitor the position, speed, and force of each lifting point in real time and transmit the information to the central processing unit. The central processing unit then precisely controls the movement of each lifting point based on preset synchronization parameters. A comprehensive inspection and maintenance of the equipment is performed before any lifting operation. S2. Dynamic load control: An intelligent hoisting operation control system is used to monitor and analyze acceleration, velocity, and displacement parameters during the hoisting process in real time. Dynamic loads are predicted based on beam parameters and the hoisting equipment operation is optimized and controlled. A buffer device composed of elastic elements is installed between the hoisting equipment and the beam. S3. Defect detection and treatment during the prefabrication stage: Before prefabricated T-beams leave the factory, ultrasonic testing and radar testing non-destructive testing technologies are used to conduct comprehensive defect detection on the beams. For the defects detected, pressure grouting and local excision repair measures are adopted according to the type and severity; S4. Optimize the lifting point settings: Based on the structural characteristics, dimensional parameters and weight distribution of the precast concrete T-beam, use finite element analysis software to simulate and determine the optimal lifting point locations and number; set up a lifting point reinforcement structure composed of reinforcement elements at the determined lifting point locations; S5. Fixing and protection of the beam: Before lifting, use adjustable clamps to firmly connect the beam to the lifting equipment; install protective pads made of rubber or nylon flexible materials at the contact points between the beam and the lifting equipment and at the points where stress concentration occurs.

2. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The sensors of the high-precision synchronous control system include a position sensor, a speed sensor and a pressure sensor, which are respectively used to monitor the position, speed and force of each hanging point in real time.

3. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The algorithms used by the intelligent lifting operation control system include a dynamic load prediction algorithm based on a neural network and an adaptive control algorithm to achieve accurate optimization of the lifting equipment operation.

4. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The ultrasonic testing in the non-destructive testing technology adopts a multi-channel ultrasonic testing instrument, which can simultaneously test multiple parts of the beam body.

5. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The thickness of the steel plate in the lifting point reinforcement structure is 8-15 mm, and the steel plate and the beam body are connected by welding, and the welding length is not less than 2 / 3 of the circumference of the steel plate.

6. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The adjustable clamp includes two symmetrically arranged clamping arms, the inner sides of which are provided with anti-slip pads. The clamping arms are opened and closed by a hydraulic drive device, and the adjustment range is adapted to precast concrete T-beams of different sizes.

7. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: The thickness of the protective pad is 20-50 mm, and the surface of the protective pad in contact with the beam body is provided with a concave-convex texture.

8. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: In the synchronization control of the hoisting equipment, the preset synchronization parameters include that the position deviation of each hoisting point does not exceed ±5mm, the speed deviation does not exceed ±0.05m / s, and the force deviation does not exceed 5% of the design value.

9. The method for erecting precast concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: In the dynamic load control, the acceleration in the lifting stage does not exceed 0.5m / s², the steering angular velocity in the translation stage does not exceed 0.1rad / s, and the impact coefficient in the beam dropping stage is controlled within 1.

2.

10. The method for erecting prefabricated concrete T-beams to avoid stress concentration during the hoisting process according to claim 1, characterized in that: During the defect detection and treatment in the prefabrication stage, the grouting material used in the pressure grouting is epoxy resin modified cement slurry, the compressive strength of which is not less than 1.2 times the design strength of the beam concrete.

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