Modular intelligent protection system for bridge parallel steel wire bundle cable against vehicle fire explosion

Abstract

The application discloses a bridge parallel steel wire bundle cable modular intelligent protection system against vehicle combustion explosion, comprising: a composite protection structure is coated on the outer surface of the parallel steel wire bundle cable, comprising a continuous fireproof layer and a modular impact resistance part; the impact resistance part comprises a plurality of protection modules arranged along the cable axial direction and capable of being independently detached, which are installed outside the fireproof layer and used for weakening the damage of external impact load to the cable and the fireproof layer; an intelligent monitoring and diagnosis unit comprises a data monitoring module and a data diagnosis module, the data monitoring module is used for collecting impact pressure signals, and the data diagnosis module is used for evaluating the protection performance of the fireproof layer, and specifically comprises: the impact pressure signals are compared with the damage threshold of internal compaction or crushing of the fireproof and heat insulation material in the fireproof layer in real time, so that the structural integrity and the residual fireproof safety margin of the fireproof layer after impact are quantitatively evaluated, and the damage positioning is associated with a specific damaged module in the protection module.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of safety protection of large-span bridge structures, and particularly relates to a modular intelligent protection system for bridge parallel steel wire bundle cable modules resisting vehicle combustion and explosion. BACKGROUND

[0002] In related technologies, as the core load-bearing component of large-span cable bridges, the service safety of parallel steel wire bundle cables directly determines the disaster resistance and durability of the overall structure. However, the bridge parallel steel wire bundle cable protection technology capable of effectively resisting the "impact-fire" strong coupling sequence caused by vehicle combustion and explosion has become an urgent engineering problem to be solved.

[0003] Existing cable protection measures mainly focus on corrosion and fire protection, and generally use PE sheath, fireproof paint or wrapped aerogel felt. However, such protection systems have a fundamental failure risk when facing the extreme working condition of vehicle combustion. Vehicle combustion has a unique "impact-fire" strong coupling feature: the overpressure shock wave and high-speed fragments generated in the detonation moment will first have a violent peeling and puncturing effect on the cable protection layer. Since the existing PE sheath and fireproof materials are generally brittle, they are prone to large-area fragmentation and falling under the action of the shock wave. Therefore, before the "jet fire" stage arrives, the fireproof layer of the cable may have been completely peeled off due to the impact, resulting in a fatal situation of "damage before burning, thermal protection failure". In order to solve the problem of cable impact protection, Chinese patent CN113605233A discloses a fire and explosion-proof bridge cable protection system. The scheme connects the outer sealing sleeve through multiple separate hoops and tension springs, trying to use the elastic deformation of mechanical springs to buffer the impact. This mechanical spring shock-absorbing design not only has a complex structure and a large volume, but also when facing the super-high pressure shock wave of vehicle combustion, its limited elastic travel is prone to instant bottoming out failure, and cannot provide effective energy dissipation.

[0004] More importantly, the existing protection technology has the fatal defect of diagnostic failure. Even if the cable only suffers a single impact event, the impact is easy to cause hidden damage such as compaction or crushing in the internal fireproof material. Such damage is difficult to be found by traditional visual inspection, conventional point inspection and infrared imaging, etc., resulting in the problem of "damage invisible and state unknown" operation and maintenance. If the cable encounters a fire in the "injured and not detected" state, its fire resistance limit will be much lower than the design expectation, bringing disastrous and unpredictable major risks to the bridge. Chinese patent CN117344621A discloses a fireproof protection and early warning monitoring system suitable for cable-stayed bridges. The patent judges whether a fire or pipeline leakage occurs by monitoring the water level and water temperature, and replenishes water by using the principle of communicating vessels. However, this "fluid-thermal" monitoring logic is extremely fragile in the face of vehicle explosions: the shock wave generated by the explosion is easy to directly destroy its complex hydraulic pipeline and thin-walled sleeve, causing the system to instantly fail, and completely unable to diagnose whether the physical compaction or crushing damage of the fireproof material has occurred.

[0005] Therefore, the industry urgently needs to break through the limitations of the existing protection system "single function, fragile structure, and blind operation and maintenance", and establish a new "modular blast resistance-accurate diagnosis" mode facing the vehicle explosion limit working condition. SUMMARY

[0006] The present application aims to at least partially solve one of the technical problems in the related art. To this end, the first object of the present application is to propose a bridge parallel steel wire cable modular intelligent protection system against vehicle explosion, which effectively resists the initial shock wave and subsequent high-temperature fire generated by vehicle explosion through the design of modular impact resistance part and efficient fireproof layer. At the same time, through the integrated intelligent monitoring and diagnosis unit, not only the quantitative evaluation of the hidden damage (such as compaction and crushing) of the internal fireproof layer can be realized, but also the damage can be accurately located to the specific damaged module, thereby providing key technical support for disaster emergency rescue decision and post-disaster rapid repair.

[0007] To achieve the above object, the first aspect of the present application proposes a bridge parallel steel wire cable modular intelligent protection system against vehicle explosion, comprising:

[0008] The composite protection structure is wrapped on the outer surface of the parallel steel wire cable, comprising a continuous fireproof layer and a modular impact resistance part; the impact resistance part comprises a plurality of independently detachable protection modules arranged along the axial direction of the cable, which are installed outside the fireproof layer and used to weaken the damage of external impact load to the cable and the fireproof layer;

[0009] The intelligent monitoring and diagnosing unit comprises a data monitoring module and a data diagnosing module, the data monitoring module is used for collecting the impact pressure signal, and the data diagnosing module is used for comparing the impact pressure signal with an internal compaction or crushing damage threshold of the fireproof and heat-insulating material in the fireproof layer in real time, so as to quantitatively evaluate the structural integrity and the residual fireproof safety margin of the fireproof layer after the impact, and to locate the damage to a specific damaged module in the protection module, thereby evaluating the protection performance of the fireproof layer.

[0010] In addition, the bridge parallel steel wire strand cable modular intelligent protection system against vehicle fuel explosion according to the above-mentioned embodiments of the present application can further have the following additional technical features:

[0011] According to an embodiment of the present application, the composite protection structure further comprises a corrosion-resistant layer; the corrosion-resistant layer is an HDPE sleeve, which is wrapped on the outer surface of the cable; the fireproof layer is a single-layer or double-layer aerogel blanket, which is wound on the outer surface of the corrosion-resistant layer through staggered joint.

[0012] According to an embodiment of the present application, the composite protection structure further comprises a weather-resistant layer; the weather-resistant layer is a fluorocarbon coating layer, which is sprayed on the outermost side of the protection module.

[0013] According to an embodiment of the present application, the protection module comprises a rigid puncture-resistant layer and a flexible buffer layer; the rigid puncture-resistant layer is a modular detachable stainless steel sleeve, which is directly installed on the surface of the fireproof layer and used for guiding the impact load to diffuse along the axial direction and weaken the local concentrated effect; the flexible buffer layer is a super-elastic polyurea material, which is sprayed on the surface of the rigid puncture-resistant layer, so as to form a coordinated buffer and energy absorption structure; the protection module further comprises an intumescent thin-layer fireproof coating layer, which is sprayed on the surface of the flexible buffer layer.

[0014] According to an embodiment of the present application, the modular detachable stainless steel sleeve is composed of a plurality of standard protection segments along the axial direction, each of the standard protection segments is composed of a first semicircular plate and a second semicircular plate which are separated along the circumferential direction and buckled, and the specific connection structure is as follows:

[0015] Radial joint: the longitudinal side edge of the first semicircular plate is provided with a U-shaped side plate, the corresponding side edge of the second semicircular plate is provided with a straight side plate, and the two are fastened and connected through the first bolt penetrating the U-shaped side plate and the straight side plate; at the same time, the side edge joint of the first semicircular plate is provided with a lateral lap plate extending inwardly, and the lateral lap plate is padded on the inner side of the joint of the second semicircular plate, so as to form a radial sealing structure.

[0016] Axial splicing: between two adjacent standard protection segments, through the connecting lug plate arranged at the end of the first and second semicircular arc plates and the second bolt, axial fastening connection is realized; wherein, the end lap plate is arranged at the end joint of the standard protection segment, and is inserted into the interior of the adjacent standard protection segment, so as to ensure the sealing and continuity of the axial joint of the rigid puncture-resistant layer.

[0017] According to one embodiment of the present application, the data monitoring module comprises a flexible piezoelectric film sensor array, a signal acquisition circuit and a signal conditioning unit; the flexible piezoelectric film sensor array is arranged between the fireproof layer and the rigid puncture-resistant layer, for converting the impact load into an impact pressure signal, and transmitting the impact pressure signal to the signal conditioning unit through the signal acquisition circuit, and the signal conditioning unit pre-processes the impact pressure signal.

[0018] According to one embodiment of the present application, the data diagnosis module comprises a storage unit; the storage unit pre-stores the material damage threshold of the fireproof layer, and the damage threshold at least comprises a compaction threshold and a crushing threshold; the compaction threshold is the critical impact pressure corresponding to the beginning of the significant decline of the heat insulation performance of the fireproof layer due to the irreversible compaction of the pore structure; the crushing threshold is the critical impact pressure corresponding to the crushing and loss of structural integrity of the fireproof layer.

[0019] According to one embodiment of the present application, the data diagnosis module further comprises a data processing unit and a data transmission unit; the data processing unit is not only used for automatically identifying the damage state of the fireproof layer and triggering a graded early warning according to the signal of the flexible piezoelectric film sensor array, but also used for locating the damage and associating it to a specific impact damaged module; the data transmission unit is used for sending the data containing the graded early warning signal and the damage location information to the bridge health monitoring system or the emergency rescue command center.

[0020] According to one embodiment of the present application, the diagnosis method executed by the intelligent monitoring and diagnosis unit comprises the following steps:

[0021] S1, acquisition and positioning: the impact event signal is captured through the sensor array in the data monitoring module, and the impact is preliminarily located to a specific damaged module according to the response of each sensor in the array;

[0022] S2, processing and comparison: the impact pressure signal at the location is extracted by the data diagnosis module, and is compared with the compaction threshold and the crushing threshold pre-set for the fireproof and heat insulation material in the fireproof layer;

[0023] S3, graded early warning:

[0024] When the impact pressure signal is less than the compaction threshold, it is determined that the fireproof layer is basically intact, and a three-level early warning is triggered;

[0025] When the impact pressure signal is greater than or equal to the compaction threshold value and less than the crushing threshold value, it is determined that the fireproof layer is compacted and damaged, and a secondary early warning is triggered;

[0026] When the impact pressure signal is greater than or equal to the compaction threshold value and less than the crushing threshold value, it is determined that the fireproof layer is compacted and damaged, and a secondary early warning is triggered;

[0027] S4, information transmission: data containing early warning level and positioning identification information is sent to the bridge health monitoring system or emergency rescue command center.

[0028] Compared with the prior art, the present application has the following remarkable beneficial effects:

[0029] (1) Modular rigid-flexible coordination, eradication of "damage before burning" hidden dangers. The present application constructs a modular rigid-flexible coordination impact-resistant part with excellent energy dissipation capacity through the synergistic design of modular stainless steel sleeve and super-elastic buffer layer. This structure can effectively disperse and shield the violent shock waves and fragments generated by vehicle combustion and explosion, and can effectively prevent the damage of the internal fireproof material and the cable body. Compared with the traditional "integrated winding" protection, the segmented modular structure of the present application not only significantly reduces the risk of compaction, puncture and crushing of the fireproof layer, but also fundamentally solves the problem of "local damage leading to overall failure" of the protection structure after impact, ensuring that the cable still has a complete and efficient heat shield in the subsequent fire.

[0030] (2) Damage rapid evaluation and positioning, solving the problem of "damage not detected". The present application innovatively couples the impact sensing with the compaction threshold and crushing threshold depth of the fireproof layer material, not only realizing the quantitative evaluation of the hidden damage of the internal fireproof layer, but also having the ability to accurately locate the specific damaged module, which effectively solves the technical problem of "unintuitive judgment and inability to locate the source" of the traditional cable protection system damage.

[0031] (3) Empowering emergency decision-making in disaster, improving the efficiency of post-disaster rescue. The present application integrates the detachable modular structure with the locatable intelligent diagnosis, providing key decision support for the "golden rescue period" in disaster. After the occurrence of extreme accidents such as vehicle combustion, the system can immediately feedback the real safety state and damaged location of the cable to the emergency command center, assisting decision-makers to quickly judge whether the bridge has the ability to pass through rescue vehicles, greatly improving the protection capability and emergency response efficiency of the bridge structure in the event of disaster.

[0032] Additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a schematic diagram of a cable multi-level composite protection structure according to an embodiment of the present application;

[0034] Figure 2 Fig. 1 is a schematic diagram of the overall arrangement of the cable protection system according to an embodiment of the present application;

[0035] Figure 3 Fig. 2 is a schematic diagram of the cross section of the cable multi-level composite protection structure according to an embodiment of the present application;

[0036] Figure 4 Fig. 3 is a schematic diagram of the standard segment of the cable multi-level composite protection structure according to an embodiment of the present application;

[0037] Figure 5 Fig. 4 is a flow chart of the working principle of the cable protection system according to an embodiment of the present application.

[0038] Reference signs:

[0039] 1, cable; 2, anticorrosion layer; 3, fireproof layer; 4, impact resistance part; 41, rigid puncture resistance layer; 411, first semicircular arc plate; 412, second semicircular arc plate; 413, U-shaped side plate; 414, straight side plate; 415, first bolt; 416, lateral lap plate; 417, connecting lug plate; 418, second bolt; 419, end lap plate; 42, flexible buffer layer; 43, fireproof coating layer; 5, weather-resistant layer; 6, data monitoring module; 61, flexible piezoelectric film sensor array; 62, signal acquisition circuit; 63, signal conditioning unit; 7, data diagnosis module; 71, storage unit; 72, data processing unit; 73, data transmission unit. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below with reference to the accompanying drawings, in which like or similar elements or elements having the same or similar functions are denoted by the same or similar reference signs throughout the drawings. The embodiments described below by reference to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0041] A bridge parallel steel wire cable modular intelligent protection system against vehicle fuel explosion is provided according to an embodiment of the present application.

[0042] As shown in Figures 1 to 4 Fig. 1, the bridge parallel steel wire cable modular intelligent protection system against vehicle fuel explosion according to an embodiment of the present application comprises a composite protection structure and an intelligent monitoring and diagnosis unit.

[0043] The composite protection structure is coated on the outer surface of the parallel steel wire bundle cable, and includes a continuous fireproof layer 3 and a modular impact-resistant part 4; the impact-resistant part 4 includes a plurality of protection modules arranged along the axis of the cable 1 and independently detachable, which are installed outside the fireproof layer 3 and used to weaken the damage of external impact load to the cable 1 and the fireproof layer 3. It should be noted that in the embodiment of the present application, the cable 1 is a parallel steel wire bundle cable, and in order to avoid being too long, the parallel steel wire bundle cable is abbreviated as cable hereinafter.

[0044] The intelligent monitoring and diagnosis unit includes a data monitoring module 6 and a data diagnosis module 7, the data monitoring module 6 is used to collect the impact pressure signal, and the data diagnosis module 7 is used to evaluate the protection performance of the fireproof layer 3, specifically including: comparing the impact pressure signal with the damage threshold of internal compaction or crushing of the fireproof and heat insulation material in the fireproof layer 3 in real time, to quantitatively evaluate the structural integrity and remaining fire safety margin of the fireproof layer 3 after impact, and locate and associate the damage to a specific damaged module in the protection module.

[0045] The intelligent monitoring and diagnosis unit includes a data monitoring module 6 and a data diagnosis module 7, the data monitoring module 6 is used to collect the impact pressure signal, and the data diagnosis module 7 is used to compare the impact pressure signal with the damage threshold of internal compaction or crushing of the fireproof and heat insulation material in the fireproof layer 3 in real time, to quantitatively evaluate the structural integrity and remaining fire safety margin of the fireproof layer 3 after impact, and locate and associate the damage to a specific damaged module in the protection module, thereby evaluating the protection performance of the fireproof layer 3.

[0046] The intelligence of the system is reflected in the deep integration of the "intelligent monitoring and diagnosis unit" and the protection structure. The data monitoring module 6 collects key signals such as pressure distribution and time history curve in the impact event in real time through the distributed sensor network embedded in the impact-resistant part 4 module. Then, the data diagnosis module 7 compares these real-time signals with the "damage threshold" determined in advance through material experiments - this threshold accurately corresponds to the critical state of irreversible damage such as internal compaction and crushing of the fireproof and heat insulation material under impact. Through this real-time comparison, the system can go beyond qualitative judgment and achieve quantitative evaluation of the structural integrity of the fireproof layer 3, and accurately calculate its remaining fire safety margin.

[0047] Finally, the system realizes the closed-loop management from perception, diagnosis to precise positioning. The diagnosis module can not only evaluate the attenuation of the overall protection performance, but also associate the identified damage signal with the physical location of the specific sensor, so as to precisely locate the specific "damaged module" in the protection layer composed of a large number of independent modules. This provides clear instructions for subsequent maintenance actions, ensuring that the performance degradation can be repaired or replaced in a timely manner, thereby continuously ensuring the ultimate safety of the bridge cable 1 in the face of extreme fire and impact combined disasters while efficiently utilizing resources.

[0048] According to one embodiment of the present application, the composite protection structure further comprises a corrosion protection layer 2; the corrosion protection layer 2 is an HDPE sleeve, which is wrapped on the outer surface of the cable 1; the fire protection layer 3 is a single-layer or double-layer aerogel felt, which is wrapped on the outer surface of the corrosion protection layer 2 through staggered joint.

[0049] Specifically, the composite protection structure introduces an HDPE sleeve as the core corrosion protection layer 2, which builds the first active defense line extending outward from the cable 1 matrix. This dense HDPE sleeve tightly wraps the outer surface of the cable 1, effectively isolates external moisture and oxygen, prevents cable 1 steel wire corrosion, and serves as the installation base for the subsequent efficient fire protection layer 3. On this basis, the system innovatively uses a single-layer or double-layer aerogel felt as the fire protection layer 3 outside the corrosion protection layer 2, with a total thickness of 5mm~10mm. Unlike the outer modular impact resistance part 4, this layer adopts an axial continuous wrapping method, which is tightly wrapped through the "staggered joint" process, and the overlap rate is preferably about 52%. This continuous structure can completely eliminate the "thermal bridge" effect, ensuring that the internal HDPE sleeve does not melt and the steel wire does not anneal under high-temperature combustion and explosion. Therefore, not only does it ensure the overall continuity and integrity of the fire protection layer 3, but it also completely eliminates the thermal bridge effect and provides excellent fire-resistant and heat-insulating protection for the cable 1 in a fire scenario.

[0050] Therefore, the design of this "corrosion protection-fire protection" double-layer structure realizes precise division of functions and synergistic effect of performance. The inner HDPE sleeve focuses on solving the problem of electrochemical corrosion of the cable 1 in the long-term service environment, while the outer aerogel felt fire protection layer 3 is specialized in dealing with the threat of short-term extreme high temperature fire; the combination of the two constitutes a composite protection system that takes into account the daily and emergency, long-term and short-term safety throughout the cycle. What is particularly key is that the aerogel felt adopts a staggered wrapping construction process, so that the fire protection layer 3 is not prone to form a through weak link at the joint when encountering external impact or structural deformation, thereby further physically strengthening the overall stability and reliability of the fire protection layer 3 as the basis for the impact resistance part 4.

[0051] According to one embodiment of the present invention, the composite protective structure further includes a weather-resistant layer 5; the weather-resistant layer 5 is a fluorocarbon coating, which is sprayed on the outermost side of the protective module.

[0052] Specifically, this composite protection system features an additional high-performance weather-resistant layer 5 on its outermost side. This layer is typically made of fluorocarbon coating applied uniformly to the outer surface of all modular impact-resistant parts 4, with a preferred coating thickness of 20μm to 50μm. This coating forms the first line of defense against the natural environment, exhibiting excellent resistance to ultraviolet radiation, acid and alkali spray corrosion, and aging. It effectively resists ultraviolet radiation, acid rain erosion, and atmospheric aging, significantly improving the service life of the modular stainless steel sleeve and polyurea layer. Furthermore, as the exterior surface of the replaceable modules, the weather-resistant layer 5 can be configured with specific colors according to the bridge's aesthetic requirements, ensuring visual consistency after module replacement.

[0053] Therefore, by introducing the fluorocarbon coating weather-resistant layer 5, not only is the appearance and durability of the protective module greatly improved throughout its entire life cycle, but it also protects the underlying impact-resistant layer 4 and fireproof layer 3 from direct damage by environmental factors, ensuring the long-term effectiveness and stability of the core protective functions. This enables the entire intelligent protection system to cope with extreme impacts and fire risks while also possessing excellent adaptability to daily environments, achieving comprehensive safety assurance from special event protection to all-weather durable maintenance.

[0054] According to one embodiment of the present invention, the protective module includes a rigid puncture-resistant layer 41 and a flexible buffer layer 42; the rigid puncture-resistant layer 41 is a modular, detachable stainless steel sleeve, which is directly installed on the surface of the fireproof layer 3 to guide the impact load to diffuse axially and weaken the local concentrated effect; the flexible buffer layer 42 is a superelastic polyurea material, which is sprayed on the surface of the rigid puncture-resistant layer 41 to form a synergistic buffer energy absorption structure; the protective module also includes an intumescent thin-film fireproof coating 43 sprayed on the surface of the flexible buffer layer 42.

[0055] Specifically, the protective module, through a composite design of a rigid puncture-resistant layer 41 and a flexible buffer layer 42, constructs a synergistic gradient buffer energy-absorbing structure, which is a key barrier protecting the internal brittle aerogel felt from impact damage. The inner layer of the protective module is a modular, detachable stainless steel sleeve, which is a solid shell structure formed by two semi-circular arc plates radially joined together by high-strength bolts. When encountering high-speed fragments or sharp object impacts from vehicle combustion and explosion, the stainless steel sleeve effectively prevents punctures due to its metallic rigidity; at the same time, it utilizes the shell structure characteristics to diffuse the concentrated impact load over a large area on the rigid surface, providing physical shielding and preventing the internal aerogel felt from being locally crushed or punctured.

[0056] The flexible buffer layer 42 is sprayed on the surface of the modular stainless steel sleeve, which is preferably a super-elastic polyurea material with a spraying thickness of 2-5 mm. The polyurea material has excellent viscoelasticity and elongation at break, can deform greatly at the moment of arrival of the explosion shock wave, thereby absorbing and dissipating a large amount of impact energy. In addition, it cooperates closely with the internal stainless steel sleeve to form a "soft (energy absorption and wave dissipation) -hard (rigid shielding)" composite impact-resistant structure. This structure not only uses polyurea to prolong the impact time, but also uses the steel sleeve to block the penetration of fragments, achieving efficient resistance to vehicle explosion complex load.

[0057] The fireproof coating 43 is an intumescent thin-layer fireproof coating, which is uniformly sprayed on the outside of the flexible buffer layer 42 (i.e. the polyurea layer), and the dry film thickness is preferably 10-30 μm. Since organic elastomer materials such as polyurea are easily burned or softened when directly exposed to flame, the fireproof coating 43 as the first heat barrier of the standard protection module can rapidly expand and form a dense heat-insulating carbon layer at the initial stage of fire, thereby effectively delaying the thermal decomposition of the internal polyurea layer and ensuring that the impact-resistant part 4 can still maintain the integrity of the structure under high temperature in fire.

[0058] According to one embodiment of the present application, the modular detachable stainless steel sleeve is composed of a plurality of standard protection segments connected in the axial direction. Each standard protection segment is composed of a first semicircular plate 411 and a second semicircular plate 412 separated in the circumferential direction, and the thickness is preferably 0.5-1.0 mm. The specific connection structure is as follows:

[0059] Radial connection (embrace structure): the longitudinal side of the first semicircular plate 411 is provided with a U-shaped side plate 413, and the corresponding side of the second semicircular plate 412 is provided with a straight side plate 414. The two are tightly fixed by the first bolt 415 penetrating the U-shaped side plate 413 and the straight side plate 414, and the two semicircular plates are tightly embraced and fixed on the outside of the fireproof layer 3. At the same time, the side of the first semicircular plate 411 is provided with a lateral lap plate 416, which is inserted into the joint of the second semicircular plate 412 to form a radial sealing structure, thereby preventing external corrosive media or explosion flame from penetrating along the joint.

[0060] Axial connection (series structure): the connection between the two adjacent standard protection segments is achieved by the connection lug plate 417 and the second bolt 418 arranged at the end of the first semicircular plate 411 and the second semicircular plate 412. In order to adapt to the slight deformation of the cable 1 during operation and ensure sealing, an end lap plate 419 is arranged at the end joint of the standard protection segment, and is inserted into the inside of the adjacent standard protection segment to ensure the sealing and continuity of the axial connection of the rigid anti-penetration layer 41.

[0061] According to an embodiment of the present application, the data monitoring module 6 comprises a flexible piezoelectric film sensor array 61, a signal acquisition circuit 62 and a signal conditioning unit 63; the flexible piezoelectric film sensor array 61 is arranged between the fireproof layer 3 and the rigid puncture-resistant layer 41, for converting impact load into impact pressure signals and transmitting the impact pressure signals to the signal conditioning unit 63 through the signal acquisition circuit 62, and the signal conditioning unit 63 pre-processes the impact pressure signals.

[0062] Specifically, the core sensing element of the data monitoring module 6 is the flexible piezoelectric film sensor array 61, which is precisely arranged at the key interface between the fireproof layer 3 and the rigid puncture-resistant layer 41. This arrangement enables it to directly sense and capture the impact stress transmitted through the outer layer buffer, accurately capture the effective impact pressure that penetrates the outer steel jacket and actually acts on the internal aerogel felt, and at the same time use the steel jacket as an electromagnetic shielding layer to avoid external noise interference; and efficiently convert it into corresponding charge signals (i.e. original impact pressure signals). Subsequently, through the integrated signal acquisition circuit 62, these preliminary electrical signals are transmitted in real time to the signal conditioning unit 63.

[0063] The signal conditioning unit 63 pre-processes the received original impact pressure signals, usually including key steps such as amplifying weak signals, filtering out environmental noise interference, and digitizing conversion. The signal-to-noise ratio and accuracy of the conditioned impact pressure signals are significantly improved, laying a reliable data foundation for the backend diagnosis module to accurately compare and quantitatively evaluate the damage threshold, thereby ensuring the accuracy and reliability of the entire intelligent monitoring and diagnosis system in response to impact events.

[0064] According to an embodiment of the present application, the data diagnosis module 7 comprises a storage unit 71; the storage unit 71 pre-stores the material damage threshold of the fireproof layer 3, which at least includes a compaction threshold and a pulverization threshold; the compaction threshold is the critical impact pressure corresponding to the beginning of the significant decline in the thermal insulation performance of the fireproof layer 3 due to irreversible compaction of the pore structure; the pulverization threshold is the critical impact pressure corresponding to the occurrence of breakage and loss of structural integrity of the fireproof layer 3. Among them, the compaction threshold and the pulverization threshold can be obtained by conducting drop hammer impact tests on the aerogel felt material at different energy levels, combined with the microstructure characterization and thermal insulation performance test of the material after the test.

[0065] According to one embodiment of the present application, the data diagnostic module 7 further comprises a data processing unit 72 and a data transmission unit 73; the data processing unit 72 is not only used for automatically identifying the damage state of the fireproof layer 3 according to the signals of the flexible piezoelectric thin film sensor array 61 and triggering a hierarchical early warning, but also used for locating the damage and associating it to a specific impact damaged module; the data transmission unit 73 is used for sending data containing the hierarchical early warning signal and the damage location information to the bridge health monitoring system or the emergency rescue command center.

[0066] Specifically, the storage unit 71 of the data diagnostic module 7 is its knowledge base for accurate diagnosis, in which the key performance thresholds of the fireproof layer 3 material are pre-stored, mainly including two core damage thresholds of “compaction threshold” and “crushing threshold”. Among them, the “compaction threshold” is defined as the critical impact pressure value at which the unique micro-pore structure of the fireproof layer 3 (such as aerogel blanket) begins to collapse and compact irreversibly, resulting in a significant attenuation of its thermal insulation performance; while the “crushing threshold” corresponds to the critical impact pressure at which the fireproof layer 3 material macroscopically breaks, completely loses structural integrity and bearing capacity. These two thresholds together constitute a complete damage criterion for evaluating the performance degradation to structural failure of the fireproof layer 3.

[0067] The data processing unit 72 is the “brain” of the entire diagnostic module, which intelligently analyzes the pre-processed impact pressure signals from the signal conditioning unit 63 based on the damage thresholds in the storage unit 71. This unit not only can automatically compare the real-time impact pressure with the pre-set compaction threshold and crushing threshold, so as to accurately identify the fireproof layer 3 in different damage states such as “intact”, “performance attenuation” or “structural failure”, and trigger the corresponding hierarchical early warning accordingly; but also can accurately locate the identified damage position by analyzing the spatial signal distribution of the sensor array, and associate it to a specific, physically addressable protection module, realizing the leap from “state evaluation” to “module positioning”.

[0068] Finally, the data transmission unit 73 is responsible for efficiently outputting the diagnostic conclusions generated by the data processing unit 72. It will send the key information including the specific hierarchical early warning level, the damage severity, and the specific damaged module number associated, in a standardized data format, to the bridge health monitoring system at the next level in real time through wired or wireless network, providing accurate guidance for structure maintenance; at the same time, when triggering high-level early warning, it can also send alarm information to the emergency rescue command center, providing immediate and reliable data support for post-disaster emergency response and rescue decision-making, thus forming a complete closed loop from perception, diagnosis to decision support.

[0069] Specifically, when the vehicle explosion extreme disaster occurs, the working principle of the modular composite protection structure is as follows: ① primary thermal protection: the weather-resistant layer 5 and the fireproof coating 43 first play a role, and preliminarily resist the high temperature and thermal radiation in the explosion instant; ② flexible energy absorption: most of the impact energy is absorbed and dissipated by the flexible buffer layer 42 through its viscoelastic properties and large deformation effect; ③ rigid shielding: the remaining impact energy or high-speed explosion fragments impact is physically blocked and stress is dispersed by the modular stainless steel sleeve, thereby effectively preventing the internal brittle material from being penetrated or crushed; ④ core heat insulation: thanks to the above multi-level coordinated protection, the internal high-efficiency fireproof layer 3 (aerogel blanket) can remain intact, thereby playing an excellent heat insulation performance (resisting a high temperature of 1000 DEG C or above) in the subsequent high-temperature fire disaster, and ensuring that the steel wire of the cable 1 does not anneal or strength degradation.

[0070] According to one embodiment of the present application, as shown in Figure 5 the diagnostic method performed by the intelligent monitoring and diagnosis unit includes the following steps:

[0071] S1, collection and positioning: the impact event signal is captured by the sensor array in the data monitoring module 6, and the impact is preliminarily positioned to a specific damaged module according to the response of each sensor in the array.

[0072] That is, when an external impact event occurs, the flexible piezoelectric film sensor array 61 is triggered. The data processing unit 72 first locks the number of the specific damaged protection module impacted according to the physical coding of the sensor array.

[0073] S2, processing and comparison: the data diagnosis module 7 extracts the impact pressure signal "P" at the positioning position, and compares it with the compaction threshold value "P C " and the crushing threshold value "P F " of the fireproof and heat insulation material in the fireproof layer 3.

[0074] S3, graded early warning:

[0075] When the impact pressure signal is less than the compaction threshold value (P C ), it is determined that the fireproof layer is basically intact, and a three-level early warning is triggered to prompt that an impact event has occurred;

[0076] When the impact pressure signal is greater than or equal to the compaction threshold value and less than the crushing threshold value (P C ≤P<P F ), it is determined that the fireproof layer is compacted and damaged, and the heat insulation performance is reduced, and the system triggers a two-level early warning to prompt the emergency rescue personnel that the impact damage in this area is serious and the fire safety margin is reduced;

[0077] When the impact pressure signal is greater than or equal to the crushing threshold value (P≥P FWhen the fireproof layer is damaged and loses the heat insulation function, the system triggers a first-level early warning, prompting the emergency rescue personnel that the structure cannot resist the subsequent fire and the bridge should be immediately closed.

[0078] S4, information transmission: data containing early warning level and positioning identification information are sent to the bridge health monitoring system or emergency rescue command center.

[0079] That is, the data transmission unit 73 sends the data packet containing the above-mentioned graded early warning signals (first, second and third early warning) and positioning identification information (specific impact position) to the bridge health monitoring system cloud platform and the emergency rescue command center through wired or wireless means.

[0080] In summary, the present application integrates the modular composite protection structure and the intelligent monitoring and diagnosis unit, not only realizes efficient protection of the cable against vehicle fuel explosion, but also solves the problem of "unknowing and difficult positioning" of hidden damage through precise positioning and quantitative diagnosis of specific damaged modules and internal fireproof layers. This provides key technical support for post-disaster rapid modular replacement and emergency rescue decision-making, and significantly improves the service resilience and recovery efficiency of the bridge structure under vehicle fuel explosion extreme disasters.

[0081] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0082] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0083] In this application, unless otherwise clearly indicated and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise clearly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0084] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A modular intelligent protection system for parallel steel wire strand cable of a bridge against vehicle fire explosion, characterized in that, The composite protection structure is coated on the outer surface of the parallel steel wire bundle cable and comprises a continuous fireproof layer and a modular impact resistance part; the impact resistance part comprises a plurality of independently detachable protection modules arranged along the axial direction of the cable and installed on the outside of the fireproof layer to weaken the damage of external impact load to the cable and the fireproof layer; the protection module comprises a rigid puncture resistance layer and a flexible buffer layer; An intelligent monitoring and diagnosis unit comprises a data monitoring module and a data diagnosis module; the data monitoring module is used for collecting impact pressure signals; the data diagnosis module is used for comparing the impact pressure signals with the internal compaction or crushing damage threshold of the fireproof and heat insulation material in the fireproof layer in real time to quantitatively evaluate the structural integrity and residual fire safety margin of the fireproof layer after impact and to associate the damage location to a specific damaged module in the protection module, thereby evaluating the protection performance of the fireproof layer; The data monitoring module comprises a flexible piezoelectric film sensor array, a signal acquisition circuit and a signal conditioning unit; the flexible piezoelectric film sensor array is arranged between the fireproof layer and the rigid puncture resistance layer and is used for converting the impact load into the impact pressure signals and transmitting the impact pressure signals to the signal conditioning unit through the signal acquisition circuit; the signal conditioning unit pre-processes the impact pressure signals; The data diagnosis module comprises a storage unit; the storage unit pre-stores the material damage threshold of the fireproof layer, wherein the damage threshold at least comprises a compaction threshold and a crushing threshold; the compaction threshold is the critical impact pressure corresponding to the time when the heat insulation performance of the fireproof layer starts to significantly decrease due to the irreversible compaction of the pore structure; the crushing threshold is the critical impact pressure corresponding to the time when the fireproof layer is broken and loses structural integrity. The composite protection structure further comprises a corrosion prevention layer; the corrosion prevention layer is an HDPE sleeve coated on the outer surface of the cable; the fireproof layer is a single-layer or double-layer aerogel felt wound on the outer surface of the corrosion prevention layer through staggered joint.

2. The modular intelligent protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 1, wherein, The composite protection structure further comprises a weather resistance layer; the weather resistance layer is a fluorocarbon coating layer sprayed on the outermost side of the protection module.

3. The modular intelligent protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 1, wherein, The rigid puncture resistance layer is a modular detachable stainless steel sleeve directly installed on the surface of the fireproof layer and is used for guiding the axial diffusion of impact load and weakening the local concentration effect; the flexible buffer layer is a super-elastic polyurea material sprayed on the surface of the rigid puncture resistance layer to form a coordinated buffer and energy absorption structure; the protection module further comprises an intumescent thin-layer fireproof coating layer sprayed on the surface of the flexible buffer layer.

4. The modular smart protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 1, wherein, The modular detachable stainless steel sleeve is formed by splicing a plurality of standard protection segments along the axial direction; each standard protection segment is formed by buckling a first semicircular plate and a second semicircular plate separated along the circumferential direction, and the specific connection structure is as follows:

5. The modular intelligent protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 4, wherein, ​ Radial splicing: the longitudinal side of the first semicircular plate is provided with a U-shaped side plate, the corresponding side of the second semicircular plate is provided with a straight side plate, and the two are fastened and connected by the first bolt penetrating the U-shaped side plate and the straight side plate; at the same time, the inside of the side seam of the first semicircular plate is provided with a lateral lap plate, which is inserted into the inside of the joint of the second semicircular plate to form a radial sealing structure; Axial splicing: between two adjacent standard protection segments, the connecting lug plate provided at the end of the first semicircular plate and the second semicircular plate and the second bolt are used to realize the fastening connection in the axial direction; wherein, the end lap plate is provided at the end seam of the standard protection segment, and is inserted into the inside of the adjacent standard protection segment to ensure the sealing and continuity of the axial connection of the rigid puncture-resistant layer.

6. The modular smart protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 1, wherein, The data diagnosis module further comprises a data processing unit and a data transmission unit; the data processing unit is not only used for automatically identifying the damage state of the fireproof layer and triggering a graded warning according to the signal of the flexible piezoelectric film sensor array, but also used for locating the damage and correlating it to a specific impact damaged module; the data transmission unit is used for sending data containing the graded warning signal and damage positioning information to a bridge health monitoring system or an emergency rescue command center.

7. The modular smart protection system against vehicle fire explosion of bridge parallel steel wire strand cable of claim 6, wherein, The diagnosis method executed by the intelligent monitoring and diagnosis unit comprises the following steps: S1, acquisition and positioning: the impact event signal is captured by the sensor array in the data monitoring module, and the impact is preliminarily located to a specific damaged module according to the response of each sensor in the array; S2, processing and comparison: the data diagnosis module extracts the impact pressure signal at the positioning position, and compares it with the compaction threshold and the crushing threshold of the fireproof and heat insulation material in the fireproof layer; S3, graded warning: When the impact pressure signal is less than the compaction threshold, it is determined that the fireproof layer is basically intact, and a three-level warning is triggered; When the impact pressure signal is greater than or equal to the compaction threshold and less than the crushing threshold, it is determined that the fireproof layer is compacted, and a two-level warning is triggered; When the impact pressure signal is greater than or equal to the crushing threshold, it is determined that the fireproof layer is crushed, and a one-level warning is triggered; S4, information transmission: data containing the warning level and positioning identification information is sent to a bridge health monitoring system or an emergency rescue command center.

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