An assembled laminated floating slab damping system and a mounting method thereof

Abstract

The application discloses an assembled laminated floating slab damping system and a mounting method thereof, and aims to solve the problems of high rigidity, narrow damping frequency band, low construction efficiency, difficult maintenance and the like of the existing floating slab damping system; in the system, upper and lower prefabricated concrete slabs are bonded into a laminated floating slab through a composite slab, the laminated floating slab can provide high damping and a flexible interface, effectively dissipate vibration energy, and can jointly form a multistage damping system with an elastic pad plate to expand the damping effect; connecting pieces are overlapped on two laminated floating slabs, and connecting pad plates are arranged between the laminated floating slabs and the connecting pieces; the connecting pad plates are integrally formed with an elastic layer through a steel plate and vulcanization, and can additionally provide elastic connection and reduce stress concentration.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of vibration and noise control of rail transit, and particularly relates to an assembled composite floating slab vibration reduction system and a mounting method thereof. BACKGROUND

[0002] With the rapid development of urban rail transit, vibration and noise control has become a key issue to ensure operation safety, improve passenger comfort and reduce environmental impact. As a core solution, the track vibration reduction system is widely used in subway, light rail and other lines, aiming to attenuate vibration energy through structural optimization and material innovation. However, existing vibration reduction technologies, especially floating slab systems, still have many limitations, which are difficult to meet the increasingly improved performance requirements.

[0003] I. Existing vibration reduction technologies and their limitations

[0004] The current mainstream track vibration reduction system mainly includes floating slab track bed, elastic sleeper and vibration reduction fastener, etc. These technologies have alleviated vibration transmission to some extent, but there are the following key problems:

[0005] 1. Conflict between structural rigidity and vibration reduction performance: Traditional prefabricated floating slab mostly adopts monolithic prefabricated concrete structure, whose natural frequency is usually high (20-30 Hz), which is difficult to effectively isolate low-frequency vibration (such as 5-15 Hz frequency band during train start and stop). This leads to narrow vibration reduction frequency band, and insufficient vibration control for sensitive areas (such as hospitals and residential areas). At the same time, high rigidity design easily causes stress concentration, accelerates material fatigue, and shortens service life.

[0006] 2. Low efficiency of construction and maintenance: The monolithic floating slab has large volume and weight (single piece can reach several tons), which needs to rely on large lifting equipment during transportation and installation in underground space, has long construction period (more than 28 days for cast-in-place maintenance), and is limited by narrow tunnel environment, which is low in efficiency. In addition, the existing system is designed to be non-detachable, and maintenance or replacement needs to damage the track bed structure, which is high in cost and interrupts operation.

[0007] 3. Insufficient damping energy dissipation mechanism: Traditional materials (such as ordinary concrete or rubber pad) have limited damping characteristics and low energy dissipation efficiency. Vibration energy is mainly absorbed by elastic deformation, lacking active energy dissipation mechanism, which leads to the attenuation of vibration reduction effect under long-term load. For example, rubber pad is prone to aging and hardening, with a damping ratio decrease of >30%, affecting the sustained performance.

[0008] 4. Poor adaptability: The existing system is difficult to flexibly adjust the rigidity or frequency to match different line conditions (such as curve section or different axle load). The tolerance of prefabricated components is not well matched, and gaps are easily generated during on-site assembly, which leads to the invasion of slag and water, causing diseases such as empty hanging and loosening, and increasing the maintenance frequency.

[0009] For example, the application number CN202110836351.6, a kind of assembled adjustable floating plate track, the patent discloses "the longitudinal rail body has two, parallel arrangement. The rail body is set on the longitudinal rail body according to certain interval. The connecting body is arranged between the two parallel longitudinal rail body, for connecting longitudinal rail body. The method gives a kind of block type floating plate structure, but the scheme does not have the vibration absorption capacity of low frequency band, the overall damping effect is insufficient;

[0010] The application number CN202010852133.7, a kind of track bed vibration absorber and track bed vibration absorption system, the patent discloses "the glue melting steel plate part, the glue melting steel plate part is arranged on the damping vibration pad, the glue melting steel plate part includes at least one glue melting steel plate;Chemical anchor bolt, the chemical anchor bolt is embedded and fixed in the track bed;Limiting seat, the limiting seat is buckled in the both ends of the glue melting steel plate part, and is connected and fixed with the chemical anchor bolt on the track bed. The present application provides a kind of vibration absorption scheme on the basis of line has been opened operation, can further enhance the effect of vibration reduction and noise reduction. The scheme introduces glue melting steel plate part, enhances the vibration absorption effect, but still adds damping structure on the basis of traditional floating plate system, not fundamentally change the principle of vibration reduction and noise reduction, the overall vibration reduction and noise reduction effect is limited.

[0011] II. Technical development needs

[0012] In view of the above problems, the industry urgently needs a new damping system, which has:

[0013] 1. Wideband damping capability: expand the effective damping frequency band to the low frequency domain (<20Hz), while maintaining high frequency performance.

[0014] 2. Modular and assembly design: realize lightweight, detachable structure, simplify construction process and reduce dependence on large equipment.

[0015] 3. Intelligent material integration: introduce high-damping composite materials to improve energy dissipation efficiency and support dynamic stiffness adjustment.

[0016] 4. Environmental adaptability: adapt to underground space constraints, support rapid installation and maintenance, and reduce life cycle cost.

[0017] Based on this, the laminated structure, composite material and prestressed technology are studied in depth, and an assembly type laminated floating plate damping system and its installation method are proposed. The system breaks through the traditional limitations through double-layer laminated floating plate design, vulcanization composite interface and prestressed bolt adjustment, expands the vibration isolation range, improves the vibration reduction and noise reduction effect, shortens the construction and maintenance period, and improves the adaptability. SUMMARY

[0018] In order to overcome the above problems, a prefabricated laminated floating slab damping system and its installation method are designed to solve the problems of high stiffness, narrow damping frequency band, low construction efficiency, and difficult maintenance of the existing floating slab damping system. In the system, the upper and lower prefabricated concrete slabs are bonded to form a laminated floating slab through a composite slab, which can provide high damping and flexible interface, effectively dissipate vibration energy, and jointly form a multi-stage damping system with an elastic pad to expand the damping effect. The connecting piece is overlapped on the two laminated floating slabs, and the connecting pad is arranged between the laminated floating slab and the connecting piece, which is vulcanized with the steel plate and the elastic layer to form an elastic connection and reduce stress concentration.

[0019] Specifically, the purpose of the present application is to provide a prefabricated laminated floating slab damping system, which comprises two laminated floating slabs 1 laid along the longitudinal direction,

[0020] A connecting piece 2 is arranged between the two laminated floating slabs 1, and the connecting piece 2 transversely connects a plurality of laminated floating slabs 1.

[0021] The laminated floating slab 1 and the connecting piece 2 are both provided with an overlapping structure, so that the side edge of the connecting piece 2 is overlapped on the laminated floating slab 1, and a connecting pad 3 is arranged between the laminated floating slab 1 and the connecting piece 2 in the overlapping area.

[0022] Among them, the laminated floating slab 1 comprises an upper slab 11, a composite slab 12 and a lower slab 13 arranged in turn from top to bottom;

[0023] Among them, the upper slab 11 and the lower slab 13 are both concrete slabs;

[0024] The composite slab 12 comprises an upper steel plate layer 121, an elastic layer 122 and a lower steel plate layer 123 which are vulcanized integrally;

[0025] Preferably, the elastic layer is a rubber layer or a polyurethane layer.

[0026] Among them, the laminated floating slab 1 further comprises a longitudinal bolt 4 with prestress;

[0027] The longitudinal bolt 4 is screwed through the upper slab 11 and the composite slab 12 from top to bottom and extends into the lower slab 13.

[0028] Among them, a rail bearing platform 5 is arranged on the top of the laminated floating slab 1;

[0029] An elastic pad 6 is arranged on the bottom of the laminated floating slab 1 in the form of point paving or strip paving.

[0030] Among them, the connecting pad 3 comprises an upper longitudinal section 31, a transverse section 32 and a lower longitudinal section 33 connected in turn.

[0031] The upper longitudinal section 31 and the lower longitudinal section 33 both comprise a vulcanized integrated double-layer steel plate and an elastic layer therebetween;

[0032] The transverse section 32 comprises an elastic layer;

[0033] The elastic layer is a rubber layer or a polyurethane layer.

[0034] The connecting piece 2 is a long groove-shaped member prefabricated from reinforced concrete,

[0035] The connecting piece 2 is overlapped on the composite floating slab 1 on both sides;

[0036] A transverse bolt 7 with prestress is arranged on the inner side of the connecting piece 2; the transverse bolt 7 is screwed through the wall surface of the connecting piece 2 and the connecting pad plate 3 and extends into the composite floating slab 1.

[0037] An additional plate 8 is arranged in the middle of the interior of the connecting piece 2; a plurality of additional plates 8 are sequentially connected along the extension direction of the steel rail;

[0038] A second longitudinal bolt 81 is further arranged on the additional plate 8, and the additional plate 8 is screwed and fixed on the connecting piece 2 through the second longitudinal bolt 81.

[0039] Micro-expansion fine aggregate concrete 9 is filled in the gap between the additional plate 8 and the wall surface in the interior of the connecting piece 2.

[0040] The application further provides a mounting method of the assembled composite floating slab vibration reduction system, and the method comprises the following steps.

[0041] Step 1, foundation preparation and positioning:

[0042] The roadbed surface is cleaned, C20 fine aggregate concrete is laid as a leveling layer, and the flatness error is ensured to be below 3mm / 2m.

[0043] The installation positions of the composite floating slab 1 and the connecting piece 2 are marked by positioning with a flexible line, and bolt hole positions are reserved;

[0044] Step 2, laying of the elastic pad plate 6:

[0045] The elastic pad plate 6 is laid by points or strips and temporarily fixed by using an adhesive; when laid by points, the interval is 300-500mm; when laid by strips, the interval is below 100mm;

[0046] The flatness is checked, and the height difference of the top surfaces of all the vibration reduction pads is ensured to be below 1mm;

[0047] Step 3, hoisting and positioning of the composite floating slab 1:

[0048] Using a small gantry crane with a load of 5 tons, the composite floating slab 1 is hoisted onto the elastic pad 6, and is gently placed to avoid impact;

[0049] Adjust the position of the composite floating slab 1 so that the embedded connecting node is aligned with the connecting node of the opposite composite floating slab, with an error of ±2mm;

[0050] Step 4, install the intermediate connecting piece 2:

[0051] Align the connecting node of the connecting piece 2 with the side connecting node of the composite floating slab 1, and embed the connecting pad 3;

[0052] Insert the transverse bolt 7, initially tighten it, and the torque reaches 50-70N·m, keeping the gap between the composite floating slab 1 and the connecting piece 2 below 5mm;

[0053] Step 5, apply pre-stress and system adjustment:

[0054] Use a hydraulic torque wrench to tighten the transverse bolt 7 and the longitudinal bolt 4 in stages;

[0055] Initial tightening: apply 50% of the designed pre-stress, check the gap between the slabs,

[0056] Final tightening: apply 100% pre-stress, and simultaneously monitor the elevation and deformation of the composite floating slab through a laser level;

[0057] Step 6, gap treatment and final fixation:

[0058] Fix the additional slab 8 on the connecting piece 2, and pour micro-expanding fine aggregate concrete 9 between the additional slab 8 and the wall surface of the connecting piece 2, and vibrate it to compact it; the expansion rate of the micro-expanding fine aggregate concrete is 0.02%-0.05%

[0059] Cover the curing film and water for 7 days, and prohibit load disturbance during this period.

[0060] The beneficial effects of the present application include:

[0061] (1) The assembled composite floating slab vibration reduction system provided by the present application, the composite floating slab of the system is designed in a laminated structure, the combination of the double-layer steel plate and the composite plate breaks through the high stiffness limitation of the traditional monolithic floating slab, realizes the "rigid and flexible" vibration reduction mechanism, and the vulcanization interface of the composite plate provides uniform damping to avoid stress concentration;

[0062] (2) The assembled composite floating slab vibration reduction system provided by the present application, a plurality of bolts with pre-stress are arranged in the system, controllable pre-stress is applied through the bolts, the adjustable range of the system stiffness reaches 30-100kN / mm, so that the vibration suppression demand of different frequencies, including low-frequency isolation and high-frequency absorption, can be adapted;

[0063] (3) The assembly type laminated floating slab damping system provided by the application adopts modular assembly, and devices such as laminated floating slabs and connecting pieces are prefabricated in a factory and quickly spliced on site, without cast-in-place maintenance, so that the construction period is shortened to 7 days, individual part replacement is supported, and the maintenance cost is reduced by 60%; and the dependence on large equipment is reduced, and the adaptability to underground space construction is enhanced;

[0064] (4) In the assembly type laminated floating slab damping system provided by the application, the elastic layer of the composite slab adopts high-loss-factor rubber (η≥0.3), and the energy dissipation efficiency is improved by 50%; and the micro-expansion fine stone concrete in the system can ensure the connection durability and reduce shrinkage cracks;

[0065] (5) The assembly type laminated floating slab damping system provided by the application can adjust the overall natural frequency to 8-15 Hz, and the transmission rate is less than 0.2 (above 50 Hz frequency band), which is suitable for sensitive environments such as city centers and hospital surroundings, by setting the laminated floating slab, connecting piece and connecting pad;

[0066] (6) The composite material selected in the assembly type laminated floating slab damping system provided by the application has better anti-aging performance, and the service life can reach more than 30 years, and the maintenance interval is extended to 10 years; the concrete consumption is reduced by 20%, the carbon emission is reduced, and the whole life cycle cost is reduced by 40%;

[0067] (7) The assembly type laminated floating slab damping system provided by the application can match different track types, such as subways, light rails or heavy load railways, by adjusting the prestress or replacing the elastic parts. BRIEF DESCRIPTION OF DRAWINGS

[0068] Figure 1 The overall structure schematic diagram of the assembly type laminated floating slab damping system provided by the application is shown;

[0069] Figure 2 The structure schematic diagram of the cross section of the assembly type laminated floating slab damping system provided by the application is shown;

[0070] Figure 3 The structure schematic diagram of the composite slab in the assembly type laminated floating slab damping system provided by the application is shown;

[0071] Figure 4 The structure schematic diagram of the connecting pad in the assembly type laminated floating slab damping system provided by the application is shown. REFERENCE NUMERALS

[0072] 1-composite floating slab; 11-upper plate; 12-composite plate; 121-upper steel plate layer; 122-elastic layer; 123-lower steel plate layer; 13-lower plate; 2-connector; 3-connection pad; 31-upper longitudinal section; 32-transverse section; 33-lower longitudinal section; 4-longitudinal bolt; 5-bridge bearing platform; 6-elastic pad; 7-transverse bolt; 8-additional plate; 81-second longitudinal bolt; 9-micro-expansion fine stone concrete. DETAILED DESCRIPTION

[0073] The application will be further described in details by the accompanying drawings and examples. The features and advantages of the application will become more apparent through these descriptions.

[0074] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Although various aspects of implementations can be presented in terms of methods, other aspects can also be implemented as appropriate throughout this disclosure, such as any methods claimed or described herein, whether or not described or claimed as such.

[0075] The application provides a prefabricated composite floating slab vibration reduction system, as shown in Figure 1 and Figure 2 , the system comprises two composite floating slabs 1 laid along the longitudinal direction, i.e. the direction in which the steel rail extends. The length of the composite floating slab can be selected according to the construction requirements.

[0076] A connector 2 is arranged between the two composite floating slabs 1, which transversely connects multiple composite floating slabs 1; that is, the length of the connector 2 can be greater than the length of the composite floating slab 1.

[0077] An overlapping structure is arranged on both the composite floating slab 1 and the connector 2, that is, the inner side of the composite floating slab 1 is narrow at the top and wide at the bottom, forming a stepped structure, and correspondingly, the two ends / outer side of the connector 2 is wide at the top and narrow at the bottom, forming an inverted stepped structure, so that the side edges of the connector 2 overlap on the composite floating slab 1. A connection pad 3 is arranged between the composite floating slab 1 and the connector 2 in the overlapping area, as shown in Figure 4 .

[0078] In a preferred embodiment, as shown in Figure 3 ; the composite floating slab 1 comprises an upper plate 11, a composite plate 12 and a lower plate 13 arranged in sequence from top to bottom;

[0079] Among them, the upper plate 11 and the lower plate 13 are both concrete plates; the concrete plates are reinforced concrete plates or prestressed concrete plates; the upper plate 11 and the lower plate 13 are completely separated by the composite plate 12;

[0080] The composite plate 12 comprises a vulcanized integrated upper steel plate layer 121, an elastic layer 122 and a lower steel plate layer 123.

[0081] Preferably, the elastic layer is a rubber layer or a polyurethane layer.

[0082] In the present application, the traditional whole floating slab is adjusted to be a combination of two superimposed floating slabs and connecting pieces, and can be assembled on site, which reduces the difficulty of transporting large prefabricated components in underground space, and also solves the difficulty of cast-in-place concrete components in limited underground space.

[0083] In the present application, the original whole floating slab is replaced by the superimposed floating slab 1, which can be split into the upper plate 11 and the lower plate 13, thereby reducing the stiffness and natural frequency of the superimposed floating slab 1, expanding the frequency range of vibration reduction, and increasing the effect of vibration reduction.

[0084] At the same time, since the composite plate 12 is introduced, the composite plate 12 participates in vibration when the superimposed floating slab 1 is subjected to train load vibration reduction, and the composite plate 12 greatly increases the damping of the superimposed floating slab 1, which is beneficial to vibration reduction and energy dissipation.

[0085] In a preferred embodiment, the upper plate 11 and the lower plate 13 of the superimposed floating slab 1 are made of C50 / C60 prestressed concrete or high-performance reinforced concrete, with a compressive strength ≥ 50 MPa and an aggregate particle size ≤ 16 mm.

[0086] The composite plate 12 is made of ethylene propylene diene rubber (EPDM) or polyurethane (hardness 50-60 Shore A), and is integrally formed with two 0.8-1.2 mm thick galvanized steel plates through high-temperature vulcanization (140-160°C, 10-15 MPa pressure), with a bonding strength ≥ 2.5 MPa. In the present application, the above vulcanization process can remove the gas inside the elastic layer, ensure the product density, size accuracy, and promote heat conduction.

[0087] The specific prefabrication process is as follows:

[0088] Pouring of the lower plate 13: pouring the bottom layer of concrete in the mold, and pre-burying the connecting nodes (such as stainless steel sleeves);

[0089] Laying of the composite plate 12: laying the vulcanized composite plate 12 (steel plate-rubber-steel plate) on the surface of the un-solidified concrete, and ensuring the interface adhesion by vibrating;

[0090] Pouring of the upper plate 11: pouring the upper layer of concrete on the composite plate 12, pre-burying the connecting nodes (such as stainless steel sleeves), and curing for 28 days (under standard conditions);

[0091] In the above pouring process, the pre-buried sleeves in the concrete have a hole diameter that is 2-4 mm larger than the diameter of the bolt, which facilitates later adjustment.

[0092] In a preferred embodiment, the laminated floating slab 1 further comprises longitudinal bolts 4 with prestress;

[0093] The longitudinal bolts 4 are screwed from top to bottom through the upper plate 11 and the composite plate 12 and extend into the lower plate 13. The longitudinal bolts 4 in the present application are used to apply vertical prestress to the laminated floating slab 1, and the overall stiffness, natural frequency and deformation of the laminated floating slab 1 can be adjusted by the application of prestress. In the present application, controllable prestress is applied by bolts, so that the adjustable range of system stiffness is 30-100 kN / mm, which can adapt to the vibration suppression requirements of different frequencies, including low-frequency isolation or high-frequency absorption.

[0094] In a preferred embodiment, a rail bearing platform 5 is provided on the top of the laminated floating slab 1; the rail bearing platform is provided with a steel rail.

[0095] An elastic pad 6 of point paving or strip paving is provided at the bottom of the laminated floating slab 1, and the foundation vibration isolation is provided by the elastic pad 6 to further reduce vibration transmission.

[0096] The elastic pad 6 is made of natural rubber or polyurethane foaming material, with a density ≥ 900 kg / m³ and a fatigue resistance ≥ 10^6 cycles.

[0097] The shape can be cylindrical (diameter 100-150 mm, height 20-30 mm) or strip-shaped (width 100-200 mm, length matching the laminated floating slab).

[0098] Production process: mold forming and vulcanization treatment, and the surface needs to be coated with an anti-aging coating (such as a polyurethane coating).

[0099] In a preferred embodiment, as shown in Figure 4 The connecting pad 3 comprises an upper longitudinal section 31, a transverse section 32 and a lower longitudinal section 33 connected in sequence;

[0100] The upper longitudinal section 31 and the lower longitudinal section 33 both comprise a double-layer steel plate and an elastic layer therebetween which are vulcanized as a whole.

[0101] The transverse section 32 comprises an elastic layer; that is, the transverse section 32 only has an elastic layer and does not need to be provided with a steel plate.

[0102] The elastic layer on the connecting pad 3 is a rubber layer or a polyurethane layer.

[0103] The upper longitudinal section 31 and the lower longitudinal section 33 are both provided with through holes for bolts to pass through, so that the bolts can pass through the connecting pad 3, thereby fixing the connecting pad 3 at a predetermined position.

[0104] By setting the connecting pad plate 3 in the application, elastic connection between the composite floating slab 1 and the connecting piece 2 can be provided, and stress concentration can be reduced.

[0105] In a preferred embodiment, the connecting piece 2 is a prefabricated long groove-shaped member of reinforced concrete, which transversely connects a plurality of composite floating slabs to form a continuous support frame to bear load, torque and vibration.

[0106] The connecting piece 2 is lapped on the composite floating slab 1 on both sides; an auxiliary member or connecting node for alignment positioning can be arranged at the lapping position to facilitate the overall splicing and installation of the composite floating slab and the connecting piece 2 system on the construction site. The auxiliary member or connecting node can be a sleeve structure, and correspondingly, a similar sleeve structure is also pre-buried in the composite floating slab 1. When the two sleeves are aligned, it is considered that the connecting piece 2 and the composite floating slab 1 are aligned, and subsequent bolt screwing can be performed.

[0107] A transverse bolt 7 with prestress is arranged on the inner side of the connecting piece 2; the transverse bolt 7 is screwed through the wall surface of the connecting piece 2 and the connecting pad plate 3 and extends into the composite floating slab 1.

[0108] Preferably, an additional slab 8 is arranged in the middle of the interior of the connecting piece 2, and a plurality of additional slabs 8 are sequentially connected along the extension direction of the steel rail;

[0109] A second longitudinal bolt 81 is further arranged on the additional slab 8, and the additional slab 8 is screwed and fixed on the connecting piece 2 through the second longitudinal bolt 81.

[0110] Micro-expanding fine stone concrete 9 is filled in the gap between the additional slab 8 and the wall surface in the interior of the connecting piece 2.

[0111] In the application, by arranging the additional slab 8 and the micro-expanding fine stone concrete 9 in the interior of the connecting piece 2, the connection strength and the gap filling can be enhanced, and the system integrity and durability can be ensured.

[0112] The application also provides an installation method of the assembled composite floating slab vibration reduction system, which comprises the following steps.

[0113] Step 1, foundation preparation and positioning:

[0114] The roadbed surface is cleaned, and C20 fine stone concrete is laid as a leveling layer to ensure that the flatness error is less than 3mm / 2m.

[0115] The installation positions of the composite floating slab 1 and the connecting piece 2 are marked by a line positioning, and bolt hole positions are reserved;

[0116] Step 2, laying the elastic pad plate 6:

[0117] Point or strip elastic pad 6, using adhesives temporary fixed; Wherein, point spacing 300-500 mm; Strip spacing 100 mm or less;

[0118] Check flatness, ensure that all vibration damping pad top surface height difference in 1 mm or less;

[0119] Step 3, composite floating plate 1 hoisting and positioning:

[0120] Using a small gantry crane load 5 tons, hoisting the composite floating plate 1 on the elastic pad 6, light to avoid impact;

[0121] Adjust the position of the composite floating plate 1, the embedded connection node and the connection node of the relative composite floating plate are aligned, the error is controlled within ± 2 mm;

[0122] Step 4, install the intermediate connecting piece 2:

[0123] The connecting node of the connecting piece 2 is aligned with the side connecting node of the composite floating plate 1, and the connecting pad 3 is embedded;

[0124] Insert the transverse bolt 7, preliminary fastening, torque reaches 50-70 N·m, keep the gap between the composite floating plate 1 and the connecting piece 2 below 5 mm;

[0125] Step 5, prestress and system adjustment:

[0126] Use hydraulic torque wrench to fasten transverse bolt 7 and longitudinal bolt 4 in stages;

[0127] Initial tightening: apply 50% of the design prestress, check the plate gap,

[0128] Final tightening: apply 100% prestress, simultaneously monitor the composite floating plate elevation and deformation through laser level;

[0129] The prestress in the application can be selected and set according to actual conditions, for example, it can be set to 200 kN, the stiffness is adjusted by prestress, increasing the prestress can increase the stiffness, which is suitable for high frequency vibration reduction, and reducing the prestress can reduce the stiffness, which is suitable for low frequency isolation.

[0130] Step 6, gap treatment and final fixation:

[0131] Fix the additional plate 8 on the connecting piece 2, and pour micro-expanding fine aggregate concrete 9 between the additional plate 8 and the wall surface of the connecting piece 2, and vibrate and compact; The expansion rate of the micro-expanding fine aggregate concrete is 0.02%-0.05%

[0132] Cover the curing film, water curing for 7 days, and prohibit load disturbance during the period.

[0133] Preferably, in the above steps, the size tolerance of the prefabricated components such as the superimposed floating slab 1 connector 2, connecting pad 3, etc. is: length and width ±2mm, thickness ±1.5mm.

[0134] The positioning error during on-site installation is: plane position ≤3mm, elevation error ≤1.5mm.

[0135] Preferably, in the superimposed floating slab 1, the upper plate 11 and the lower plate 13 are coated with an epoxy resin interface agent at the interface adjacent to the composite plate to enhance the bonding force.

[0136] The contact surface of the elastic pad 6 and the superimposed floating slab 1 needs to be roughened, such as sand blasting, to prevent slipping.

[0137] Preferably, in step 5, the bolt fastening needs to be symmetrically synchronized to avoid eccentric loading, and a multi-point torque wrench set is used.

[0138] Further preferably, after 24 hours, it is re-tightened once to make up for a loss of 5%-10%, completing the prestress loss compensation.

[0139] After completing the above installation steps, the following detection operations are performed:

[0140] Natural frequency test: hammering method to detect natural frequency, target value 8-15Hz, deviation below 10% is qualified;

[0141] Damping ratio test: logarithmic decay method, damping ratio above 0.15 is qualified;

[0142] Load test: static load test deformation below 1mm / 10kN, dynamic load test vibration transmission rate below 0.2 is qualified.

[0143] When performing the above installation steps, adjustments are made for special working conditions;

[0144] Curved segment installation: adjust the angle of the connecting plate, rotatable design, and reinforce the outside force through additional plates 8;

[0145] In areas with high groundwater level: the elastic pad 6 is replaced with closed-cell foamed polyurethane, which has a water absorption rate of less than 0.5%;

[0146] Heavy load line: increase the number of prestressed bolts, reduce the bolt spacing from 500mm to 300mm, and increase the upper limit of stiffness.

[0147] The above describes the present application in combination with preferred embodiments, but these embodiments are only exemplary and serve only to illustrate. Based on this, various substitutions and improvements can be made to the present application, which all fall within the scope of protection of the present application.

Claims

1. A fabricated composite floating slab vibration reduction system, characterized by, The system comprises two longitudinal composite floating slabs (1) laid along the longitudinal direction, A connecting piece (2) is arranged between the two composite floating slabs (1), and the connecting piece (2) transversely connects a plurality of composite floating slabs (1); An overlapping structure is arranged on the composite floating slab (1) and the connecting piece (2), so that the side edge of the connecting piece (2) overlaps on the composite floating slab (1), and a connecting pad (3) is arranged between the overlapping area of the composite floating slab (1) and the connecting piece (2); The connecting piece (2) is a prefabricated long groove-shaped member made of reinforced concrete, Both sides of the connecting piece (2) overlap on the composite floating slab (1); A prestressed transverse bolt (7) is arranged on the inner side of the connecting piece (2); the transverse bolt (7) is screwed through the wall surface of the connecting piece (2) and the connecting pad (3), and extends into the composite floating slab (1); An additional plate (8) is arranged in the middle of the connecting piece (2), and a plurality of additional plates (8) are sequentially connected along the extension direction of the rail; A second longitudinal bolt (81) is further arranged on the additional plate (8), and the additional plate (8) is screwed and fixed on the connecting piece (2) through the second longitudinal bolt (81); The composite floating slab (1) comprises an upper plate (11), a composite plate (12) and a lower plate (13) arranged in sequence from top to bottom; The upper plate (11) and the lower plate (13) are both concrete plates; The composite plate (12) comprises a vulcanized upper steel plate layer (121), an elastic layer (122) and a lower steel plate layer (123); The elastic layer is a rubber layer or a polyurethane layer.

2. The assembled composite floating slab damping system according to claim 1, wherein The composite floating slab (1) further comprises a prestressed longitudinal bolt (4); The longitudinal bolt (4) is screwed from top to bottom through the upper plate (11) and the composite plate (12), and extends into the lower plate (13).

3. The assembled composite floating slab damping system according to claim 1, wherein A rail bearing platform (5) is arranged on the top of the composite floating slab (1); An elastic pad (6) is arranged on the bottom of the composite floating slab (1).

4. The assembled composite floating slab damping system according to claim 1, wherein The connecting pad (3) comprises an upper longitudinal section (31), a transverse section (32) and a lower longitudinal section (33) connected in sequence; The upper longitudinal section (31) and the lower longitudinal section (33) both comprise a double-layer steel plate and an elastic layer therebetween which are vulcanized as a whole; The transverse section (32) comprises an elastic layer; The elastic layer is a rubber layer or a polyurethane layer.

5. The assembled composite floating slab damping system according to claim 1, wherein Micro-expanding fine stone concrete (9) is filled in the gap between the additional plate (8) and the wall surface in the interior of the connecting piece (2).

6. The mounting method of the assembled composite floating slab vibration reduction system according to any one of claims 1 to 5, characterized in that, The method comprises the following steps; Step 1, foundation preparation and positioning: Clean the surface of the roadbed, lay C20 fine stone concrete as a leveling layer, and ensure that the flatness error is less than 3mm / 2m. Step 1: Positioning with elastic line, marking the installation position of the composite floating slab (1) and the connecting piece (2), and reserving the bolt hole position; Step 2: Laying the elastic pad plate (6): Point or strip laying of the elastic pad plate (6) with temporary fixation using adhesive; when point laying, the interval is 300-500 mm; when strip laying, the interval is less than 100 mm; Check the flatness to ensure that the height difference of all damping pads is less than 1 mm; Step 3: Hoisting and positioning of the composite floating slab (1): Use a small gantry crane with a load capacity of 5 tons to hoist the composite floating slab (1) onto the elastic pad plate (6) and gently place it to avoid impact; Adjust the position of the composite floating slab (1) so that the embedded connecting node aligns with the connecting node of the opposite composite floating slab, with an error of ±2 mm; Step 4: Installation of the intermediate connecting piece (2): Align the connecting node of the connecting piece (2) with the side connecting node of the composite floating slab (1) and embed the connecting pad plate (3); Insert the horizontal bolt (7) and preliminarily tighten it with a torque of 50-70 N·m to keep the gap between the composite floating slab (1) and the connecting piece (2) below 5 mm; Step 5: Pre-stress application and system adjustment: Use a hydraulic torque wrench to tighten the horizontal bolt (7) and the vertical bolt (4) in stages; Initial tightening: apply 50% of the designed pre-stress and check the slab gap, Final tightening: apply 100% pre-stress and simultaneously monitor the composite floating slab elevation and deformation through laser level detection; Step 6: Gap treatment and final fixation: Install additional plates (8) on the connecting piece (2) and pour micro-expanding fine aggregate concrete (9) between the additional plates (8) and the connecting piece (2) wall, and vibrate and compact it; the expansion rate of the micro-expanding fine aggregate concrete is 0.02%-0.05% Cover with curing film and water curing for 7 days, during which load disturbance is prohibited.

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