CN-122013681-A - Active control system for removing arch bridge tie bars and use method

CN122013681ACN 122013681 ACN122013681 ACN 122013681ACN-122013681-A

Abstract

The invention discloses an arch bridge tie bar dismantling active control system which comprises a partition board, a pressure sensor, a concrete bearing block, an air bag and an inflation/deflation device, wherein the partition board is inserted between tie bar groups to separate tie bars, the pressure sensor is fixed on the partition board and is used for collecting pressure data between the tie bars and the partition board in real time, the concrete bearing block is arranged outside the tie bars, an inner cavity is reserved in the concrete bearing block so as to accommodate the air bag, the air bag is filled between the tie bar groups and the inner wall of the concrete anchor block, the air bag is connected with the inflation/deflation device through an air pipe, and the inflation/deflation device is used for realizing inflation, pressure stabilization, air supplement and deflation control of the air bag. According to the invention, the sizes and the inflation parameters of the partition plate and the air bag can be flexibly adjusted according to the sectional shape, the tension and the distribution density of the tie bars, and the tie bar dismantling operation of arch bridges with different types and scales is adapted.

Inventors

CHENG MINGMING
HUANG ZHENGWEN
PENG QIANG
CHENG ZHAOGANG
CUI BINGWEI
YAN GUOTAI
LI SONGGEN
LIU CHANGJUN
ZHU YONGQUAN
Yang Tonghang

Assignees

中交第二航务工程局有限公司
武汉港湾质量检测有限公司

Dates

Publication Date: 20260512
Application Date: 20260104

Claims (8)

1. The arch bridge tie bar dismantling active control system is characterized by comprising a partition board, a pressure sensor, a concrete bearing block, an air bag and an inflation/deflation device, wherein the partition board is inserted between tie bar groups to separate tie bars, the pressure sensor is fixed on the partition board and is used for collecting pressure data between the tie bars and the partition board in real time, the concrete bearing block is arranged outside the tie bars, an inner cavity is reserved in the concrete bearing block so as to accommodate the air bag, the air bag is filled between the tie bar groups and the inner wall of the concrete anchoring block, and the air bag is connected with the inflation/deflation device through an air pipe and is used for realizing inflation, pressure stabilization, air supplement and deflation control of the air bag.
2. An arch bridge tie removal active control system according to claim 1, wherein the diaphragm length is consistent with the concrete bearing blocks and is secured by temporary support in connection with the bridge deck or fixed structure.
3. An arch bridge tie-bar removal active control system as recited in claim 1, wherein the pressure sensor is mounted to the diaphragm at a location where the diaphragm contacts the tie-bar.
4. An arch bridge tie-bar removal active control system according to claim 1, wherein there are a plurality of spacers, one spacer being interposed between two adjacent tie-bars in the tie-bar cluster to ensure that the tie-bars are fully separated and have no contact interference.
5. The arch bridge tie bar dismantling active control system according to claim 1, wherein the inflation/deflation device comprises an air compressor, an electromagnetic proportional valve, an air release valve, a PLC controller and a data acquisition module, wherein the data acquisition module is connected with the pressure sensor in a signal manner and receives pressure data between the tie bar and the air bag in real time, and the PLC controller is used for controlling inflation, pressure stabilization, air supplement and deflation based on the pressure data fed back by the data acquisition module.
6. A method of using an active control system for arch bridge tie removal based on any one of claims 1-5, comprising the steps of: S1, slowly inserting the partition board into the tie bar group to ensure that each tie bar is completely separated and has no contact interference, and firmly connecting the partition board with a bridge deck or a bridge fixing structure by adopting a temporary support after the insertion is completed; s2, installing a pressure sensor on the contact surface of the separator and the tie bar, and fastening and fixing the pressure sensor to ensure that the sensor sensing surface is tightly attached to the surface of the tie bar without gaps; S3, pouring concrete bearing blocks outside the tie bar groups, ensuring that the formed cavity is completely matched with the size of the air bag, and providing a stable and rigid bearing foundation for the air bag; S4, plugging the air bag into a cavity in the concrete bearing block, and adjusting the position of the air bag to ensure that the air bag is tightly attached to the surface of the tie rod and the inner wall of the cavity; S5, obtaining the design tensile force of each tie bar through a design drawing, and correcting the tensile force value of the damaged tie bar by combining the on-site actual detection result; S6, grading and inflating the air bag according to a set speed, stopping inflating when the pressure reaches a set threshold value, recording a reference pressure value at the moment, entering a pressure stabilizing stage, regulating and controlling the air pressure, and maintaining the pressure to be stable within an allowable range; s7, pressure data in a pressure stabilizing period are recorded regularly, and a pressure change curve is formed; s8, cutting the tie bars wire by wire according to the sequence from the outer side to the inner side, monitoring data fed back by the pressure sensor in real time in the cutting process, immediately suspending cutting if the pressure drops beyond a set standard, supplementing air into the air bag, and continuing cutting operation after the pressure is restored to a set threshold value; S9, after cutting of the single tie bar is completed, the air bag is precisely controlled to slowly exhaust and shrink according to a preset speed through the inflation/deflation device, the tie bar is gradually retracted in the air bag shrinkage process, and the stable release of the tension force is realized; s10, after the gas in the air bag is completely released and the tie bar is confirmed to have no rebound sliding risk, the cut tie bar is extracted from the air bag, and a steel bar with the same diameter as the tie bar is inserted at an idle position; s11, repeating the steps S5-S10, cutting all tie bars, and finally realizing safe dismantling of all tie bars.
7. The method according to claim 1, wherein the step S7 further comprises checking whether the connection interface and cable connection state of the air bag and the inflation/deflation device are reliable, checking the reasons one by one according to the sequence of interface loosening, air bag breakage and sensor failure if the pressure fluctuation exceeds the set threshold value, screwing the nut timely if the interface loosening, replacing the standby air bag and re-detecting the air tightness if the air bag breakage is found, replacing and re-calibrating the sensor failure timely, restarting the inflation program to raise the pressure to the set threshold value after the processing is finished, and performing pressure stabilizing monitoring again until the pressure is stabilized within the allowable range.
8. The method according to claim 1, wherein in step S1, if the pressure change rate is too high during the air release, the air release rate is adjusted to be reduced or the air release is suspended, and if the arch rib or pier displacement is observed to exceed the standard, the operation is stopped immediately and emergency reinforcement measures are taken.

Description

Active control system for removing arch bridge tie bars and use method Technical Field The invention relates to the field of an active control system for removing an arch bridge tie rod. More particularly, the present invention relates to an active control system for arch bridge tie bar removal and method of use. Background The arch bridge is used as a classical large-span bearing structure, and is widely applied to traffic engineering due to reasonable stress and strong crossing capability. The tie bars are core stress members of the arch bridge, penetrate through the arch ribs to balance horizontal thrust and transfer load, and are key for guaranteeing structural balance and long-term stability. The tie rod is easy to generate multiple damages after long-term service, namely, the tie rod is aged, corroded by complex environment or carbonized and cracked by concrete, the material fatigue and the mechanical property attenuation are caused by repeated load brought by traffic increase and load upgrading, the materials such as steel, concrete and the like are naturally aged and degraded, and the local damage is caused by sudden events such as earthquake, collision and the like. When the performance of the tie rod is reduced to a limit value or serious damage occurs, the tie rod needs to be replaced in time, otherwise serious accidents such as instability of arch ribs and collapse of bridges can be caused. The arch bridge tie bar dismantling main stream adopts a passive scheme of sand bag ballasting and direct cutting, namely, stacking sand bags firstly, counteracting part of tie bar stretching force through static friction force, and then directly cutting off the tie bar by using an oxygen acetylene flame or a grinding wheel cutting machine. The scheme has the advantages of simplicity and convenience in operation and lower cost, but has a plurality of fatal defects, and cannot meet the requirements of safety, controllability, accuracy and high efficiency, namely, firstly, an unreliable bearing system, uneven flexible contact stress of sand bags and tie bars, easiness in sliding, unquantifiable friction force, strong dependence on experience and uncertainty, secondly, uncontrollable impact load, rapid release of elastic potential energy at the moment of tie bar cutting, exceeding of the bearing limit of the sand bags in impact amplitude, thirdly, high safety risk, easiness in damage and even collapse of a main structure due to impact, further risk of splash and fracture rebound of the sand bags to threaten personal safety, thirdly, no monitoring and intervention in construction, incapability of timely disposing abnormal conditions, thirdly, low efficiency, high labor intensity, great manual labor for conveying the sand bags, high risk of high-altitude operation and long period. The core contradiction of the traditional scheme is that the elastic potential energy release of the high-tension tie rod and the passive bearing system are uncontrollable, which becomes an industry bottleneck. An innovative technical scheme with the functions of actively controlling and releasing tension, monitoring states in real time and avoiding impact risks is needed, and safe, accurate and efficient implementation of demolition engineering is guaranteed. Disclosure of Invention To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a preferred embodiment of the invention provides an arch bridge tie removal active control system comprising a diaphragm, a pressure sensor, a concrete carrier, an air bladder, and an inflation/deflation device; the separator is interposed between the tie bar groups to separate the tie bars; the pressure sensor is fixed on the partition board and used for collecting pressure data between the tie bars and the partition board in real time, the concrete bearing block is arranged outside the tie bars, an inner cavity is reserved in the concrete bearing block to accommodate an air bag, the air bag is filled between the tie bar group and the inner wall of the concrete anchor block, the air bag is connected with the inflation/deflation device through an air pipe, and the inflation/deflation device is used for achieving inflation, pressure stabilization, air supplement and deflation control of the air bag. Preferably, the length of the partition plate is consistent with that of the concrete bearing blocks, and the partition plate is fixedly connected with the bridge deck or the fixed structure through temporary supports. Preferably, the pressure sensor is mounted on the diaphragm at a position where the diaphragm is in contact with the tie rod. Preferably, there are a plurality of spacers, one spacer being interposed between two adjacent tie bars in the tie bar group, ensuring that each tie bar is completely separated and free of contact interference. The PLC controller automatically triggers and controls the full flow of infla