CN113601699A - Prefabrication method of 40m simply supported box girder - Google Patents

Abstract

The application discloses a prefabricating method of a 40m simply supported box girder. The prefabricating method comprises the following steps: and (3) construction of a steel bar project: processing, binding and hoisting the steel bars; installing a template: mounting a bottom die, a side die, an inner die and an end die; construction of concrete engineering: pouring and maintaining concrete; construction of a prestress project: drawing the rubber pipe, finishing the steel strand bundle, tensioning, grouting, sealing an anchor and brushing the beam end waterproof paint; the construction method and the construction system solve the technical problems that construction cost and risk are large, and the application range of the construction method and the construction system to the high-speed railway is not large.

Description

Prefabrication method of 40m simply supported box girder

Technical Field

The application relates to the field of communication, in particular to a prefabricating method of a 40m simply supported box girder.

Background

A simple beam structure is mainly adopted by high-speed railway bridges at home and abroad, wherein a 32m/24m simple beam is the main structural form of the high-speed railway bridge.

However, when the span of the simply supported beam is larger than 32m, the problems of triple continuous beams, continuous steel structures or design change by span adjustment are usually solved, the construction cost is increased, the safety quality control difficulty is high, the risk is increased, in addition, the spanning capability is poor, and the application range of the simply supported beam to the high-speed railway is not large.

Aiming at the problems of high construction cost and risk and small application range of a high-speed railway in the related technology, an effective solution is not provided at present.

Disclosure of Invention

The application mainly aims to provide a prefabricating method of a 40m simply supported box girder, so that the problems of high construction cost, high risk and small application range of a high-speed railway are solved.

In order to accomplish the above object, according to one aspect of the present application, there is provided a prefabrication method of a 40m simply supported box girder.

The prefabricating method of the 40m simply supported box girder comprises the following steps: and (3) construction of a steel bar project: processing, binding and hoisting the steel bars; installing a template: mounting a bottom die, a side die, an inner die and an end die; construction of concrete engineering: pouring and maintaining concrete; construction of a prestress project: drawing the rubber tube, finishing the steel strand bundle, tensioning, grouting, sealing the anchor and brushing the beam end waterproof paint.

Further, the construction of the steel bar engineering comprises the following steps: processing the reinforcing steel bars by adopting a numerical control hoop bending machine and a numerical control bending machine in cooperation with manual work; binding the processed steel bars on a steel bar binding mould to obtain a steel bar framework; and hoisting the steel reinforcement framework by adopting a steel reinforcement cage hoisting tool.

Further, the concrete engineering construction comprises: performing ranking and ranking, warehouse-dividing and unloading, material inspection and warehouse discharge by combining an information management platform; mixing materials by a mixing unit to obtain concrete; pouring concrete by a construction method of gradually pouring concrete from two ends to the middle; arranging a special person to carry out water storage maintenance on the beam surface of the beam-making pedestal before initial setting of the concrete after pouring.

Further, the extraction rubber tube includes: and (4) pulling out the rubber pipe embedded in the construction process of the steel bar engineering by using a pipe pulling trolley.

Further, the tensioning comprises: and (4) carrying out prestress tensioning by adopting a full-automatic tensioning system.

Further, the mud jacking comprises: and (3) carrying out prestressed duct grouting by adopting an automatic grouting system.

Further, the construction of the prestress engineering further comprises the following steps: and when the net slurry strength reaches 80% of the strength, performing inward rotation, storage and in-site transportation operation on the precast box girder by adopting a 1000 t-grade tire type girder carrying machine.

Further, the construction of the prestress engineering further comprises the following steps: and (3) carrying out a static load test by adopting a novel prestress steel structure reaction frame and a static load test loading system, and outputting a static load test report.

Further, the installation of the inner mold comprises: and an internal mold self-driving system is adopted to automatically install the internal mold.

Further, the concrete engineering construction method further comprises the following steps: and when the strength of the concrete reaches the design requirement, automatically removing the inner mould by using an inner mould self-driving system.

In this application embodiment, adopt the mode of prefabricated 40m simply supported box girder, through the construction of reinforcing bar engineering: processing, binding and hoisting the steel bars; installing a template: mounting a bottom die, a side die, an inner die and an end die; construction of concrete engineering: pouring and maintaining concrete; construction of a prestress project: drawing the rubber pipe, finishing the steel strand bundle, tensioning, grouting, sealing an anchor and brushing the beam end waterproof paint; the purpose that the prefabricated 40m simply supported box girder replaces a triple continuous girder, a continuous steel structure or changes the design and other forms through span adjustment is achieved, so that the construction cost and the risk are effectively reduced, the technical effect of the application range of the high-speed railway is expanded, and the technical problems of high construction cost, high risk and small application range of the high-speed railway are solved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, serve to provide a further understanding of the application and to enable other features, objects, and advantages of the application to be more apparent. The drawings and their description illustrate the embodiments of the invention and do not limit it. In the drawings:

fig. 1 is a schematic flow chart of a prefabrication method of a 40m simply supported box girder according to an embodiment of the present application;

FIG. 2 is a schematic illustration of a rebar tie according to an embodiment of the present application;

fig. 3 is a schematic illustration of hoisting a steel reinforcement cage according to an embodiment of the present application;

figure 4 is a schematic diagram of an internal mold self-drive system according to an embodiment of the present application;

FIG. 5 is a schematic illustration of a concrete pour construction according to an embodiment of the present application;

FIG. 6 is a schematic illustration of a concrete pour construction according to an embodiment of the present application;

FIG. 7 is a schematic view of a pipe drawing trolley according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a fully automatic tensioning system according to an embodiment of the present application;

FIG. 9 is a schematic diagram of a fully automated grouting system according to an embodiment of the application;

FIG. 10 is a schematic view of a 1000t tire style carrier according to an embodiment of the present application;

figure 11 is a schematic view of a prestressed steel structural reaction frame according to an embodiment of the present application.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In this application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the invention and its embodiments and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the present invention can be understood by those skilled in the art as appropriate.

Furthermore, the terms "mounted," "disposed," "provided," "connected," and "sleeved" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1, the present application relates to a prefabrication method of a 40m simply supported box girder, the prefabrication method comprising:

step S101, construction of a steel bar project: processing, binding and hoisting the steel bars;

according to the embodiment of the present invention, preferably, the construction of the steel bar engineering includes:

processing the reinforcing steel bars by adopting a numerical control hoop bending machine and a numerical control bending machine in cooperation with manual work; binding the processed steel bars on a steel bar binding mould to obtain a steel bar framework; and hoisting the steel reinforcement framework by adopting a steel reinforcement cage hoisting tool.

Specifically, the steel bars are processed by a numerical control hoop bending machine and a numerical control bending machine in cooperation with manual work. When the reinforcing steel bar is processed, a short ruler is not used for measuring the length so as to reduce the error, and the error is kept within the range of +/-10 mm. When the reinforcing steel bar is cut, the reinforcing steel bars with the same diameter and size are subjected to unified blanking, the reinforcing steel bars are processed according to the material preparation sequence of 'length first and short second', the irregular conditions of horseshoe shape or bending at a fracture are avoided, joints are reduced to the greatest extent, and loss is avoided.

And bending and welding the steel bars in the semi-finished product processing area, and then conveying the steel bars to a steel bar binding mould for binding. The reinforcing steel bar protection layer adopts conical concrete cushion blocks with the same marks, the cushion blocks are arranged in a quincunx mode, the thickness of the web cushion block is 2.5cm, and the thickness of the bottom plate cushion block is 3.0 cm. The mode of artificially distributing the reinforcing steel bars is adopted, the positions of the bottom reinforcing steel bars and the web reinforcing steel bars are determined according to the positioning grooves of the reinforcing steel bar binding clamping fixture, the bottom reinforcing steel bars and the web reinforcing steel bars are placed one by one according to the designed quantity, and the reinforcing steel bars are bound to the reinforcing steel bar framework strictly according to the relevant standard requirements after the reinforcing steel bar framework is installed in place. When the bottom and web plate reinforcing steel bars are bound, workers must bind from the inner side to prevent the binding wires from entering the web plate protective layer. After the binding is finished, drawing in a steel bar internal mold supporting frame, binding the top plate and the wing plate steel bars, inspecting the quality of the steel bar framework after the binding and forming, and hoisting the steel bar framework to a beam making station by using a special gantry crane after the steel bar framework is qualified to be installed in place and enter a mold.

Binding bottom plate and web plate steel bars on a steel bar binding mould, installing a prestress reserved pipeline, assembling a steel bar internal model supporting frame, binding bridge deck steel bars, removing the steel bar internal model supporting frame, integrally hoisting a steel bar framework to a beam-making pedestal and installing in place.

After the reinforcing steel bars are bound to obtain a reinforcing steel bar framework, reinforcing steel bar protection layer cushion blocks are installed, the ends and the variable cross-section positions need to be encrypted, and the reinforcing steel bar protection layer cushion blocks are arranged according to 4 per square meter in a large plane area and are appropriately encrypted. Around the steel reinforcement cage hoist and mount, will strengthen examining to the protective layer cushion, the iron wire head of ligature cushion and reinforcing bar should not be corrected because of the hoist and mount influence causes the crooked condition of cushion in the protective layer, ensures that the cushion plays a role.

The weight of the steel bars and the rubber tubes of the steel bar framework is 72.1t, the steel bar framework is integrally hoisted by a steel bar cage hoisting device, hoisting points are arranged below the hoisting device, and the distance between the hoisting points is 1.5 m. The lifting device is characterized in that iron chains are adopted as lifting ropes and are uniformly arranged below the lifting device, and the lifting device is lifted after the inspection is qualified.

Step S102, installing a template: mounting a bottom die, a side die, an inner die and an end die;

specifically, the template is an 8mm stainless steel composite plate and comprises a bottom die, a side die, an inner die, an end die and other components. The bottom die is fixed on the beam-making pedestal, the side die is welded with the bottom die into a whole after being adjusted in place, and the internal die adopts an integral self-hydraulic internal die.

According to the embodiment of the present invention, preferably, the mounting of the inner mold includes:

and an internal mold self-driving system is adopted to automatically install the internal mold.

The integral self-propelled hydraulic internal mold self-driving system adopts an electromechanical power mode, each internal mold is provided with a set of fixed bracket and two sets of movable brackets, and each set of brackets comprises a bottom adjusting wire, an upper roller, an electromechanical system and a self-driving system; the internal mold adopts a sectional block hydraulic contraction module, a hydraulic oil way, a guide beam and a rack system. The intelligent control system realizes the functions of automatic traveling positioning, automatic leveling, automatic integral lifting, translation, automatic opening in the horizontal direction, automatic rotation of the lower chamfer to the position, automatic traveling and the like by controlling the hydraulic system and the traveling motor.

After the internal mold is inspected, a power supply is started, and the drive gear drives the chain to enable the internal mold to enter the box girder reinforcement cage at a constant speed. After the hydraulic internal mold is in place, the size of the mold plate is adjusted, the top plate of the internal mold is jacked to the designed elevation, and the hydraulic stay bar is opened to enable the side plate of the internal mold to be supported in place; installing manual spiral support rods, then finely adjusting the thickness of the inner mold bottom plate and the height of the inner mold from the middle to two ends, and adjusting the thickness of the bottom plate by using the horizontal inclined support manual spiral support rods by taking the plane of the inner mold bottom plate as a reference point; and adjusting the height of the inner mold again by taking the bottom die surface as a standard, measuring the height of the inner mold from bottom to top through the top plate blanking hole and adjusting the height of the inner mold by utilizing the vertical inclined strut manual spiral support rod. And finally, the end part is supported to the position, fine adjustment is carried out by using a transverse inclined strut manual spiral strut, the end part is adjusted to be closely attached to the end mold, the end mold is screwed down by using a bolt, and the installation of the inner mold is completed.

According to the embodiment of the present invention, preferably, after the concrete engineering construction, the method further includes:

and when the strength of the concrete reaches the design requirement, automatically removing the inner mould by using an inner mould self-driving system.

And after the pouring of the concrete of the box girder is finished and the strength reaches the design requirement, removing the internal mold. Firstly fixing the moving frame in place, connecting a power supply, loosening the jacking to remove the transverse and vertical support rods, removing bolts between the templates, then opening the hydraulic system of the inner template, retracting the hydraulic support rods, drawing the inner template in place, finally lowering the height of the inner template in place, opening the power supply, and driving the drive gear to drive the chain to rotate reversely so as to enable the inner template to be automatically ejected out of the mold at a constant speed.

The internal mold self-driving system is adopted to ensure that the automation degree of the template is high, the integral installation, the removal and the movement of the template are realized, and the working procedure time for installing and removing the template is greatly reduced. The template has good integral performance, and the construction quality of the box girder is ensured. The templates are integrally operated, the seams are few, the appearance quality of the box girder is guaranteed, and meanwhile, the turnover frequency of the templates is effectively improved through the integral operation. Green and environment-friendly, and reduces energy consumption. On the premise of ensuring the requirements of box girder quality, construction safety and the like, the integral hydraulic template is a means for directly reducing energy consumption through technical innovation, and accords with the national environmental protection and green construction concept. The investment of manpower, machinery and material resources is reduced in the prefabrication construction, and the construction quality, safety and progress are improved.

Step S103, concrete engineering construction: pouring and maintaining concrete;

according to the embodiment of the present invention, preferably, the concrete engineering construction includes:

performing ranking and ranking, warehouse-dividing and unloading, material inspection and warehouse discharge by combining an information management platform; mixing materials by a mixing unit to obtain concrete; pouring concrete by a construction method of gradually pouring concrete from two ends to the middle; arranging a special person to carry out water storage maintenance on the beam surface of the beam-making pedestal before initial setting of the concrete after pouring.

The railway engineering management platform and the engineering test intelligent management platform are management platforms established by relying on a railway informatization standard system, the platform integrates the characteristics of electronization, networking, synergy, business process and the like, and is an intelligent informatization platform with controllable working state, visual working process and traceable working result. Material management, test management and mixing management are involved; the system integrates the subsystems of a laboratory, a mixing station, a mobile phone assistant APP, a management system and the like into an integrated platform. The enterprise data management system is beneficial to material accounting statistics and process control, provides an autonomous management working platform for workers, realizes data sharing of all departments through fair division of labor, perfect information and timely data updating inside an enterprise, can check information in time, guarantees engineering quality and improves working efficiency.

After the materials enter the field, the material department carries out ranking and warehouse separation unloading, relevant data information is recorded into the management platform, an entrance acceptance bill and a test order are filled in by using a mobile phone APP, a tester carries out a raw material test, and relevant test data are automatically collected and generated and reported to a supervision acceptance and confirmation. During the material detects, valve and grit feed bin barrier door are in the locking state, and material inspection is qualified and relevant test report can unblock through the rear through the supervision acceptance and completion on cell-phone APP, just can use the material in this storehouse, has effectively avoided the material not to examine earlier with the condition emergence of touching the red line.

Concrete mixing has 2 240 mix units, adopts electronic system to ensure that raw and other materials measurement satisfies the standard requirement.

The concrete design that this engineering used is C50 level, mixes the station and concentrates the stirring, and the mix proportion of guaranteeing the concrete accords with the design requirement, under the circumstances of guaranteeing the stirring time, keeps real-time supervision aggregate water content, and dynamic adjustment aggregate water content. Whether hidden dangers exist in the material distributing machine and the delivery pump or not is checked before pouring, and the problem is prevented from occurring when pouring, so that pouring quality is not affected. After the concrete is mixed, the transportation and the pouring are ensured to be finished within 45min, and the segregation phenomenon is avoided. When pouring, the concrete is ensured to have good workability and specified slump.

The pouring sequence requires that the pouring is carried out by a construction method of gradually pouring from two ends to the middle, the pouring is carried out at one time, and the pouring thickness of each layer is not more than 30 cm. The concrete is poured into the adoption and is carried out in succession with the mode of slant segmentation, horizontal layering, and the cloth is earlier from the web unloading of 5m from the case roof beam end, backward toward the support plate position fills, and the synchronous symmetry in both sides evenly goes on, fills web and bottom plate junction and bottom plate concrete earlier, then pours the remaining concrete of bottom plate from centre form top surface preformed hole unloading to in time shakeout, vibrate closely knit and carry the thick liquid to the concrete face and receive the face floating, and case top surface elevation satisfies the design requirement in the concrete. When the web plate concrete is poured, the web plate concrete is poured synchronously and symmetrically, so that the condition that the height of the concrete surface is greatly different to cause the deflection of the inner mold or other consequences is prevented. When the web concrete is poured to the joint with the top plate surface, the top plate is finally poured. The bridge floor concrete is poured from one end to the other end, every 4m sections of the bridge floor concrete are convenient for manual vibration and slurry lifting and plastering of a slurry lifting and leveling machine, and the thickness of a top plate needs to be controlled when the top plate is poured, so that the standard exceeding cannot be realized.

Arranging a specially-assigned person to carry out water storage maintenance on the beam surface of the beam-making pedestal before initial setting of the concrete after pouring is finished, and ensuring that the maintenance is in place. The storage beam area is provided with an automatic spraying maintenance system. The side surface of the box girder, the bottom plate and the top plate are maintained by automatic spraying, and the inner box of the box girder is maintained by beam-end plugging type spraying and sprinkling. The specific curing time depends on the ambient temperature and humidity, and is generally about 10 days. It is noted that when the ambient temperature is lower than 5 ℃, the sprinkling should be stopped, and the covering and heat preservation are mainly performed. Concrete curing needs to be carried out continuously, a specially-assigned person is responsible for the concrete curing, curing water needs to be kept clean and cannot be polluted by mud, and the attractiveness and integrity of concrete are guaranteed.

Step S104, construction of prestress engineering: drawing the rubber tube, finishing the steel strand bundle, tensioning, grouting, sealing the anchor and brushing the beam end waterproof paint.

The prestressed engineering of the 40m simply supported box girder comprises the procedures of drawing a rubber drawing pipe, penetrating a finished steel strand, automatically stretching, automatically grouting, sealing an anchor, coating a beam end waterproof coating and the like. The main construction scheme is characterized in that a rubber extraction pipe is adopted for pore forming, after concrete pouring is completed, the concrete pouring starting end is observed for 6-8 hours, rubber extraction pipe trial drawing is carried out, a pipe extraction trolley is adopted for pipe extraction, and after the pipe extraction trolley is qualified, all rubber pipes are extracted; and then penetrating a finished steel strand bundle, and penetrating and using a penetrating trolley. Performing pre-tensioning when the strength of the concrete reaches 60% of the design strength, and performing primary tensioning when the strength of the concrete reaches 80% of the design strength; after the primary tensioning is finished, hoisting the box girder to a girder storage bench (maintenance bench) by using a 1000 t-grade tire type girder carrying machine for storage; when the strength and the elastic modulus of the concrete meet the design requirements and the age is not less than 10 days, performing final tensioning; and tensioning by adopting a tensioning baffle for safety protection. Performing pipeline grouting within 48 hours after the final tensioning for 24 hours, and performing grouting by using automatic grouting equipment; and (5) after grouting, sealing the anchor and coating the beam end waterproof paint.

According to an embodiment of the present invention, preferably, the extraction rubber tube includes: and (4) pulling out the rubber pipe embedded in the construction process of the steel bar engineering by using a pipe pulling trolley.

Specifically, the pipe drawing trolley uses an electric drive type self-propelled moving frame, a lifting frame, a machine head, a hydraulic pump station, an electric appliance box, an operation panel, an arc-shaped wheel, a strip-shaped wheel and the like.

After pouring of the beam body is finished, concrete is operated before final setting after initial setting, after normal operation of all parts is ensured by inspection equipment before starting, the multifunctional pipe drawing and transporting all-in-one machine is firstly started on the left side of the end head of the beam body by using an electrically-driven self-propelled system, secondary operation is carried out on the left half side and the right half side, proper intervals are adjusted, then four support legs of the equipment are jacked up, tires are enabled to be 3-5mm away from the ground and to be kept horizontal, the whole equipment can be enabled to be stable in operation period, then electric appliances of the self-propelled system are turned off, and equipment walking caused by misoperation in the operation period is prevented. And sequentially drawing pipes from bottom to top layer by layer, operating the lifting and transverse moving platform to align four pairs of strip wheels of the two pairs of arc wheels with the rubber pipe pore passages, operating a supporting crosspiece of the supporting cylinder to prop against the end template to ensure the stability of the upper operating platform, opening the clamping beam to place the rubber pipe between the four pairs of strip wheels of the two pairs of arc wheels for clamping, and operating the switch of the conveying wheel to perform pipe drawing operation in sequence.

According to an embodiment of the present invention, preferably, the tensioning includes: and (4) carrying out prestress tensioning by adopting a full-automatic tensioning system.

Specifically, the full-automatic intelligent tensioning system is used in the prestressing force tensioning, and the system can realize the automation of the full process of tensioning, standing still and anchoring of the bridge prestressing force construction.

(1) Component inspection and cleaning: the method comprises the steps of checking a member, checking whether the strength of a beam material meets the tensioning requirement, checking whether the position and the inside of a pore channel are smooth, checking whether grouting holes and the like meet the construction requirement, checking whether the position of an anchor backing plate at the end part of the beam is correct, whether the surface is smooth, whether foreign matters are not in a groove of the anchor backing plate, checking and inspecting the prestressed tendons and the anchor, and performing tensioning operation when the checking result meets the quality standard requirement.

(2) And (3) strand pulling of steel strands: the length is strictly cut according to the requirements of design drawings, and working lengths at two ends are reserved. And weaving the cut steel strands and then penetrating the steel strands into the prefabricated hole channels of the box girder.

(3) The jack is connected with a pipeline of automatic intelligent tensioning equipment, the power is switched on, each piece of equipment is inspected and debugged, and then the unblocked condition of the intelligent tensioning control computer network is inspected so as to monitor the remote data of the whole tensioning process.

(4) Installing and adjusting a jack: 1) firstly, threading a limiting plate, and checking whether the groove depth of the limiting plate corresponds to the diameter of the steel strand. Inspecting whether the working anchor enters a groove or not; 2) hoisting the jack by using an electric chain hoist, 2, enabling the steel strand to pass through the jack in a matching way by individuals, then installing a tool anchor, firmly installing the clamping piece, and checking whether the malocclusion condition exists; 3) during installation, the inspected steel strand is straight and is not wound, and the front and the back correspond to each other; 4) gradually slowly loading, manually checking and adjusting the positions of the jack, the limiting plate and the tool anchor to enable all the parts and the pipeline to be positioned on the same axis; 5) When the initial stress is applied, the change of the middle line is closely concerned, and if the change is adjusted in time.

(5) After examination in the middle inspection is finished, the intelligent tensioning equipment is started, the control system automatically loads the initial stress to the steel strand, and the length of the oil cylinder and the exposed length of the tool clamping piece are automatically measured.

(6)4 tensioning equipment start simultaneously, and 1 is as the host computer, and other 3 are as the auxiliary engine. The main machine is an operation interface, the tension force and the displacement of the jacks of the 4 oil pumps are collected and displayed in real time, and the tension forces of all levels are achieved at the two ends simultaneously; and a step-by-step control oil supply mode is adopted.

(7) And (3) after tensioning to control stress during final tensioning, holding the load for 5min, automatically measuring the length of the oil cylinder and the exposed length of the tool clamping piece by the system, and calculating an actual elongation value. The tensioning of the prestress requires double control of the tensioning force and the elongation, the tensioning force control is mainly used, the elongation is used as a check, the error between the actual elongation and a theoretical value is controlled to be +/-6%, and oil is returned for anchoring.

And after the final tensioning is finished, marking the steel bundle at the position of the anchor ring opening, and checking and confirming that the steel bundle can be cut into bundles without the phenomena of wire slipping and wire breakage after 24 hours, wherein the distance between the cut part and the tail of the clamping piece is 30-40 mm. The steel strand cutting is carried out by a grinding wheel angle grinder, and oxygen flame cutting is strictly forbidden.

According to an embodiment of the present invention, preferably, the grouting includes: and (3) carrying out prestressed duct grouting by adopting an automatic grouting system.

Specifically, the automatic intelligent mud jacking system is used to prestressed duct mud jacking, this system has realized the mud jacking slurrying of mud jacking construction, the automatic accurate control in coordination of two major key processes of vacuum mud jacking, it is high to have degree of automation, batching and mud jacking volume are accurate, it is convenient that the on-the-spot removal, high operation efficiency, reliable durable, the maintenance volume is few, characteristics such as green, this system mainly comprises switch board, high-speed system thick liquid bucket, the material loading machine, the feed bin, a water pump, the mud jacking pump, the low-speed storage vat, weighing sensor and temperature-sensing ware.

The main working contents of the grouting operation comprise preparation work before grouting, pulping, vacuumizing, grouting air release and slurry discharge, grouting pressure maintaining, pipeline cleaning, equipment cleaning and the like.

The minimum reading of the pressure gauge of the automatic intelligent grouting system is 0.01MPa, and the pressure maintaining value is set to be 0.7 MPa. Pouring weighed water, cement and a special grouting material into a stirrer, stirring for 2min, then grouting into a pipeline through a grouting pump, closing a valve at a grout outlet side when thick grout overflows from the other side, reducing a valve at a grout inlet to perform secondary grouting, and maintaining the pressure after the thick grout overflows from the other side for 3-5 min. And (5) finishing the pore canal grouting until the pressure maintaining is finished. At the moment, the valve of the vacuum pump is reversed manually, the control knob of the vacuum pump is turned to be manual, the vacuum pump pumps water to clean slurry in the pipeline, the pipeline is cleaned, and the next pore channel grouting operation is carried out.

From the above description, it can be seen that the following technical effects are achieved by the present application:

in this application embodiment, adopt the mode of prefabricated 40m simply supported box girder, through the construction of reinforcing bar engineering: processing, binding and hoisting the steel bars; installing a template: mounting a bottom die, a side die, an inner die and an end die; construction of concrete engineering: pouring and maintaining concrete; construction of a prestress project: drawing the rubber pipe, finishing the steel strand bundle, tensioning, grouting, sealing an anchor and brushing the beam end waterproof paint; the purpose that the prefabricated 40m simply supported box girder replaces a triple continuous girder, a continuous steel structure or changes the design and other forms through span adjustment is achieved, so that the construction cost and the risk are effectively reduced, the technical effect of the application range of the high-speed railway is expanded, and the technical problems of high construction cost, high risk and small application range of the high-speed railway are solved.

According to the embodiment of the present invention, preferably, after the construction of the pre-stress engineering, the method further includes:

and when the net slurry strength reaches 80% of the strength, performing inward rotation, storage and in-site transportation operation on the precast box girder by adopting a 1000 t-grade tire type girder carrying machine.

Specifically, after grouting, when the net grout strength reaches 80% of the strength, the beam can be hung and moved. The beam is moved to an inspection table to inspect the beam plate size, the protective layer thickness, the length of the leaked reinforcing steel bars and the like, and the beam is moved to a beam storage area after the inspection is finished.

The beam field adopts 1 1000 t-grade tire type beam carrying machine to carry out inward rotation, storage and in-field transportation operation of the prefabricated box beam field. Before the beam carrying machine is moved, whether parking brake is released or not is checked, and whether obstacles exist on a road in front of the moving is detected. During running, the vehicle is inching firstly to confirm that no abnormity exists and then continuously moves forwards. Before the beam carrying machine is moved, whether the direction of the wheel sets is consistent or not is checked, and whether the support oil cylinders retract or not is checked. When the whole lifting beam of the beam moving machine runs, the lifting and longitudinal movement of the lifting hook are forbidden. When the beam moving machine runs, the warning lamp is turned on to remind field operators of paying attention to safety. And (4) when abnormity occurs in the process of carrying the beam body, the beam body is required to be immediately parked for inspection and is subjected to deviation correction.

According to the embodiment of the present invention, preferably, after the construction of the pre-stress engineering, the method further includes:

and (3) carrying out a static load test by adopting a novel prestress steel structure reaction frame and a static load test loading system, and outputting a static load test report.

Specifically, the static load test system is composed of a novel prestress steel structure reaction frame and a static load test loading system. The system can automatically calculate and generate a static load bending test calculation list and automatically load and control. The static load test data is automatically generated and uploaded to a system, and load data of each loading point and displacement data of each deflection measuring point are automatically recorded and displayed. And in the test process, automatic alarm is performed when the detected data is out of limit or abnormal in loading, and loading is stopped immediately and data is stored when the loading is abnormal or emergencies such as failure, power failure and the like occur.

A40 m box girder static load test is carried out by using a railway bridge static load test automatic control system and a prestress steel structure self-balancing type static load test bed. Before a static load test, placing 4 steel buttresses (including lever beams) at the central point of a support of a static load test pedestal, hoisting and transporting box girders to the static load pedestal, mounting a bridge support and accurately placing the box girders on the steel buttresses; accurately arranging jacks according to loading points on the bridge floor, mounting a reaction frame, connecting a static load equipment power and communication line, and debugging equipment; inputting test parameters of the static load test beam into a master control computer to calculate each level of loading force values, starting a static load test loading process after rechecking is correct, carrying out balance loading on each jack by the master control according to each level of loading force values, acting the jack loading on the counter-force beam and the beam surface, and realizing the balance of the counter-force beam and the ground counter-force by utilizing a closed force system self-balancing principle; and after the static load test is finished, the system automatically stores data and outputs a static load test report.

As a specific implementation mode, during beam yard early planning, according to project construction period requirements and actual site landforms, with the goals of safety, quality and refinement, the project department communicates with province and high fingers, a construction owner and a chief deputy for many times, and finally determines the whole construction planning of three yards and one room and strictly implements the whole construction planning according to the planning through repeated argumentations.

And (4) integrally planning all water and electric lines in the precast yard, and totally embedding. All equipment power plugs in the field adopt waterproof plugs, and all main roads adopt a spraying dust suppression system. The greening is planted at two sides of the approach road and in the prefabricated yard, and the effects of tidiness, attractiveness and safety are achieved. The living area is provided with a worker entertainment and leisure square and a movable room, the amateur life of workers is enriched, and the development concept humanization is realized. And a civil education room is set, team interaction and knowledge lectures are used as activity carriers, the safety, quality, civilized construction and professional knowledge skill training education of front-line workers are enhanced, and project management specialization is realized. And (3) implementing a standardized construction management guide and combining the characteristics of the project to realize engineering construction standardization. The advantages of convenient communication of the internet are fully played, spherical monitoring is installed, propaganda and reporting are enhanced, an internal work communication group is established, construction dynamics are mastered in time, and management means informatization is achieved. Summarizing the common diseases of the beam construction and implementing the prevention measures of the common diseases. And fine construction is carried out, thick work is carried out, fine work is carried out, the whole and the details of the project meet the standard requirements, a fine management system is continuously perfected, and the daily management is refined.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (10)

1. A prefabrication method of a 40m simply supported box girder is characterized by comprising the following steps:

and (3) construction of a steel bar project: processing, binding and hoisting the steel bars;

installing a template: mounting a bottom die, a side die, an inner die and an end die;

construction of concrete engineering: pouring and maintaining concrete;

construction of a prestress project: drawing the rubber tube, finishing the steel strand bundle, tensioning, grouting, sealing the anchor and brushing the beam end waterproof paint.

2. The prefabrication method according to claim 1, wherein the steel reinforcement engineering construction includes:

processing the reinforcing steel bars by adopting a numerical control hoop bending machine and a numerical control bending machine in cooperation with manual work; binding the processed steel bars on a steel bar binding mould to obtain a steel bar framework; and hoisting the steel reinforcement framework by adopting a steel reinforcement cage hoisting tool.

3. The prefabrication method according to claim 1, wherein the concrete engineering construction includes:

performing ranking and ranking, warehouse-dividing and unloading, material inspection and warehouse discharge by combining an information management platform; mixing materials by a mixing unit to obtain concrete; pouring concrete by a construction method of gradually pouring concrete from two ends to the middle; arranging a special person to carry out water storage maintenance on the beam surface of the beam-making pedestal before initial setting of the concrete after pouring.

4. Prefabrication method as claimed in claim 1, characterised in that said drawing of the rubber tube comprises: and (4) pulling out the rubber pipe embedded in the construction process of the steel bar engineering by using a pipe pulling trolley.

5. Prefabrication method according to claim 1, characterised in that said tensioning comprises: and (4) carrying out prestress tensioning by adopting a full-automatic tensioning system.

6. Prefabrication method according to claim 1, characterised in that the grouting comprises: and (3) carrying out prestressed duct grouting by adopting an automatic grouting system.

7. The prefabrication method according to claim 1, further comprising, after the prestress engineering construction:

and when the net slurry strength reaches 80% of the strength, performing inward rotation, storage and in-site transportation operation on the precast box girder by adopting a 1000 t-grade tire type girder carrying machine.

8. The prefabrication method according to claim 1, further comprising, after the prestress engineering construction:

and (3) carrying out a static load test by adopting a novel prestress steel structure reaction frame and a static load test loading system, and outputting a static load test report.

9. The prefabrication method of claim 1, wherein said installing of said inner mold includes:

and an internal mold self-driving system is adopted to automatically install the internal mold.

10. The prefabrication method according to claim 1, further comprising, after the concrete engineering construction:

and when the strength of the concrete reaches the design requirement, automatically removing the inner mould by using an inner mould self-driving system.

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