CN110672150A - Safety monitoring method for assembled bridge support - Google Patents
Safety monitoring method for assembled bridge support Download PDFInfo
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- CN110672150A CN110672150A CN201910889473.4A CN201910889473A CN110672150A CN 110672150 A CN110672150 A CN 110672150A CN 201910889473 A CN201910889473 A CN 201910889473A CN 110672150 A CN110672150 A CN 110672150A
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Abstract
The invention relates to the field of safety monitoring, and provides a safety monitoring method for an assembled bridge support. The invention further deploys and establishes a temporary supporting rod component library and a temporary supporting rod component system on the established BIM pier stud, beneficial beam prefabricated component and BIM component management platform, combines finite element analysis and field material, designs a reasonable, safe and economic temporary supporting scheme, and in construction, the temporary supporting is provided with corresponding sensors, such as stress and displacement sensors, and the like, and the calculation result is timely returned to the BIM monitoring system through wireless transmission and acquisition technology, so that the multi-dimensional management of the temporary supporting materials, design construction and application is realized. By analyzing the data in the BIM system, the construction progress, safety and economic benefit are all controlled, so that key and control factors of the invention can be reasonably improved and solved, the engineering difficulty is reduced, the engineering progress is accelerated, and the gradual improvement of the engineering benefit is further promoted.
Description
Technical Field
The invention relates to the technical field of safety monitoring, in particular to a safety monitoring method for an assembled bridge support.
Background
The rapid development of the assembled bridge engineering, the enlargement of the engineering scale and the complexity of the structural system bring complexity and safety problems to the construction process, and greatly increase the construction risk and the construction difficulty. In order to make the construction smooth and the construction quality and precision meet the requirements of specification, design and the like, the construction is often assisted by building a temporary structure. Because the construction support is a temporary structure, the design of the construction support does not draw attention of people for a long time, and the construction support is erected according to the experience of constructors in most cases without design, and even though the construction support is a specially designed support project, the design theory is not mature enough. The support has the characteristics of various erection modes, numerous uncertain factors, large bearing load, imperfect calculation theory and the like, so that one fourth of construction accidents in China is related to the failure of the support, and huge loss is caused.
In recent years, as our country advocates green building design and construction requirements of energy saving, land saving, water saving, material saving and environmental protection, prefabricated assembled bridges receive wide attention from people. The development and application of the prefabricated bridge beam need support of material science and design concept, and the construction and installation technology has decisive influence on the development. In the construction and installation technology of the assembled bridge, the temporary support system is a very important factor related to whether hoisting can be successful and influences the safety and efficiency of construction hoisting. Therefore how to rationally set up interim support, whether can guarantee the stability of interim support in the work progress to ensure safety, high efficiency, low cost, just become the technical problem that the urgent need be solved in the construction of assembled bridge.
Disclosure of Invention
The invention aims to solve the technical problems and provides a safety monitoring method for an assembled bridge support.
Aiming at the projects with numerous prefabricated components and high construction difficulty, if the stress state of temporary support in construction cannot be fully known, the large construction risk born by the whole project can be caused, the overall economic cost of the project is increased, and the economic benefit is lowered. The invention further deploys and establishes a temporary supporting rod library and a system through the established BIM pier stud, the prefabricated capping beam component and the management platform of the BIM component, combines finite element analysis and field materials, designs a reasonable, safe and economic temporary supporting scheme, and in construction, the temporary support is provided with corresponding sensors, such as stress and displacement sensors, and the like, and the calculation result is timely returned to the BIM monitoring system through wireless transmission and acquisition technology, so that the multi-dimensional management of the temporary support, the material design, the construction and the application is realized. By analyzing the data in the BIM system, the construction progress, safety and economic benefit are all controlled, so that key and control factors of the invention can be reasonably improved and solved, the engineering difficulty is reduced, the engineering progress is accelerated, and the gradual improvement of the engineering benefit is further promoted.
Drawings
FIG. 1 is a design view of a C1 type bent cap support form; fig. 2 is a schematic cross-sectional view of a C1 type bent cap support upright 1; fig. 3 is a schematic cross-sectional view of a C1 type bent cap support upright 2; FIG. 4 is a schematic cross-sectional view of C1 type bent cap support braces and crossbrace; FIG. 5 is a schematic cross-sectional view of a C1 type bent cap support stringer; FIG. 6 is a schematic cross-sectional view of a C1 type bent cap bracket box beam; FIG. 7 is a schematic cross-sectional view of a C1 type bent cap brace platform beam; FIG. 8 is a schematic diagram of a single support created by MIDAS/Civil software; FIG. 9 is a three-dimensional view created by MIDAS/Civil software; FIG. 10 is a cross-sectional elevation view of a support created by MIDAS/Civil software; FIG. 11 is a schematic diagram of model boundary constraints; FIG. 12 is a schematic view of hoisting left stage load; FIG. 13 is a schematic view of hoisting right stage load; FIG. 14 is a schematic view of wet joint construction loads; FIG. 15 is a schematic view of combined stress analysis after the left box girder is hoisted at the first stage; FIG. 16 is a schematic diagram of displacement analysis of the left box girder after the hoisting is completed in the first stage; FIG. 17 is a schematic view of combined stress analysis after the hoisting of the right box girder at the second stage is completed; FIG. 18 is a schematic view of the displacement analysis of the second stage of the completion of the hoisting of the right box girder; FIG. 19 is a schematic view of a third stage wet joint construction combined stress analysis; FIG. 20 is a third stage wet joint construction displacement analysis schematic; FIG. 21 is a schematic view of a model buckling mode 1 analysis; FIG. 22 is a schematic view of a model buckling mode 2 analysis; FIG. 23 is a schematic view of a model buckling mode 3 analysis; FIG. 24 is a schematic view of a model buckling mode 4 analysis; FIG. 25 is a schematic view of a model buckling mode 5 analysis; FIG. 26 is a schematic view of a model buckling mode 6 analysis; FIG. 27 is a schematic view of the results of model buckling modal analysis calculations; FIG. 28 is a schematic view of stress-strain measurement point placement; FIG. 29 is a schematic view of displacement measurement point arrangement; FIG. 30 is a graph showing experimental data change trends of left side columns of a left side support when a left side box girder is hoisted; FIG. 31 is a graph showing experimental data change trends of left side columns of a left side bracket during hoisting of a right side box girder; FIG. 32 is a graph showing experimental data change trends of the left side support right side column during hoisting of the left side box girder; FIG. 33 is a graph showing experimental data change trends of right side columns of the right side support during hoisting of the right side box girder; FIG. 34 is a graph showing experimental data change trends of left side diagonal braces of a left side bracket during hoisting of a left side box girder; FIG. 35 is a graph showing experimental data change trends of left side diagonal braces of the right side bracket when the right side box girder is hoisted; FIG. 36 is a graph showing experimental data change trends of a left side support right side diagonal brace during hoisting of a left side box girder; FIG. 37 is a graph showing experimental data change of a right side diagonal brace of a right side bracket during hoisting of a right side box girder; FIG. 38 is a graph showing experimental data change trends of right side columns of the right side support when the left box girder is hoisted; FIG. 39 is a graph showing experimental data change of a right side column of a right side bracket during hoisting of a right side box girder; FIG. 40 is a graph showing experimental data change trends of left side columns of the right side support when the left side box girder is hoisted; FIG. 41 is a graph showing experimental data change trends of left side columns of the right side support during hoisting of the right side box girder; FIG. 42 is a graph showing experimental data change trends of a right side inclined strut of a right side bracket when a left side box girder is hoisted; FIG. 43 is a graph showing experimental data change trends of right side diagonal braces of a right side bracket during hoisting of a right side box girder; FIG. 44 is a graph showing experimental data change trends of left side diagonal braces of a right side bracket during hoisting of a left side box girder; FIG. 45 is a graph showing experimental data change trends of left side diagonal braces of a right side bracket during hoisting of a right side box girder; FIG. 46 is a graph showing experimental data change trends of the mid-span positions of the longitudinal beams when the left box girder is hoisted; FIG. 47 is a graph showing experimental data change trends of the mid-span position of the longitudinal beam during hoisting of the right box girder; FIG. 48 is a graph showing experimental data change trends at the joint of the left bracket longitudinal beam and the upright post 1 when the left box girder is hoisted; FIG. 49 is a graph showing experimental data change trend at the joint of the left bracket longitudinal beam and the upright post 1 when the right box beam is hoisted; FIG. 50 is a graph showing the trend of experimental data at the joint between the right side support longitudinal beam and the upright post 1 when the left side box girder is hoisted; FIG. 51 is a graph showing the trend of experimental data at the joint between the right side support longitudinal beam and the upright 1 when the right side box beam is hoisted; FIG. 52 is a graph showing experimental data change trends at the joint between the right side support longitudinal beam and the upright 2 when the left side box beam is hoisted; fig. 53 is a graph of experimental data change trend at the joint of the right side support longitudinal beam and the upright post 2 when the right side box beam is hoisted.
Detailed Description
The invention provides a safety monitoring method of an assembled bridge support, which comprises the following steps:
(1) building a temporary support rod model of the prefabricated part by using a BIM (building information model) technology, designing relevant parameters of the rod and relevant parameters of the prefabricated part, summarizing the models to form a temporary support model library, and putting the temporary support rod model into the model library to provide reference for later experiments;
(2) establishing a finite element model for the whole construction process of the assembled bridge support by using MIDAS/Civil to analyze the mechanical behavior of the whole construction process;
(3) according to the finite element calculation result, arranging a test instrument, carrying out stress monitoring and displacement monitoring on a main stressed part in the construction process, comparing the monitoring result with the finite element analysis, and verifying the safety of the construction scheme;
(4) and (3) building a temporary support safety monitoring system, combining a BIM model, butting the wireless sensing system with a monitoring system platform, and finding a monitoring position corresponding to the field sensor in the model. And recording the stress and displacement of the support in real time in the construction process.
In the invention, the fabricated bridge support is preferably a fabricated bridge capping beam temporary support; the capping beam is preferably a C1 type capping beam.
In the present invention, the relevant parameters of the rod preferably include one or more of a code, a manufacturer, a mechanical property, a material, an inventory, and a price; the relevant parameters of the prefabricated parts preferably comprise one or several of the time of delivery, dimensions, materials, mechanical properties and coding.
The invention establishes a finite element model by using MIDAS/Civil in the whole construction process of the assembled bridge support to analyze the mechanical behavior of the whole construction process, ensures the construction safety and stability of the support and determines construction monitoring measuring points.
According to the invention, based on the BIM model, a temporary support safety monitoring system is constructed, the wireless sensing system is in butt joint with a monitoring system platform, the stress and displacement of the support in construction are mastered in real time, problems can be found and solved in time, and the safety of the construction process is ensured.
The technical solution provided by the present invention is described in detail below with reference to examples.
Ganxiang city central city Gannan Dai way expressway engineering, namely a first section, a bridge in the New century (orange flavor Dai way) from the west to the west of the Gannan Dai way (Huichang way), lines are laid along the Gannan Dai way, the Changzheng Dai way and the Xingguan way of the New century, the overall length is about 4.2km, and the Gannan Jiang city expressway engineering comprises four parts, namely a main line elevated frame, a main line parallel ramp, a Dongjiang source interchange overpass and a bridge approach splicing bridge of the bridge in the New century. The total area of the newly-built bridge is about 14.47 ten thousand meters2Wherein the overall length of the main line elevated frame is 3.96km, the standard bridge width is 25m, and the area of the bridge deck is about 11.23 ten thousand m2(ii) a 3 pairs of parallel ramps in total, the total length of the ramp is about 870m, the standard bridge width is 8.5m, and the area of the bridge deck is about 0.74 ten thousand m2(ii) a The Dongjiang source full interchange overpass has 8 ramps in total, the total length is about 2.68km, and the area of the bridge deck is about 2.49 ten thousand m2(ii) a A new century bridge approach splicing bridge relates to the east approach bridge northRemoving the pavement structure of the last two bridge surfaces, splicing the pavement structure to form a bridge with the width of 4.0m and the length of 70m, and the total splicing width area of about 280m2。
The upper and lower structures (except pile foundation and bearing platform) of the bridge basically adopt a full prefabrication form, and totally comprise 650 pile foundations; 337 bearing platforms; 422 pier studs, wherein 316 pier studs are prefabricated, and 106 pier studs are cast in situ; a capping beam 143 seat, wherein a capping beam 141 seat, a cast-in-place capping beam 1 seat and a steel capping beam 1 seat are prefabricated; the box girders 249 span, wherein the precast concrete simply supported small box girders 125 span 816 pieces, the reinforced concrete combined simply supported small box girders 25 span 112 pieces, the steel structure continuous box girders 5 are connected with 14 spans, the cast-in-place reinforced concrete box girders 16 are connected with 41 spans, and the cast-in-place prestressed concrete box girders 16 are connected with 44 spans. The Gannan major expressway engineering as the key one level of the Gannan city 'four-horizontal six-vertical one-ring' expressway system is an important development axis of the city, and the construction and implementation of the Gannan major expressway engineering can greatly improve the traffic capacity of the Gannan city road network and bring greater convenience for the trip of the people.
The main construction bright spot in the engineering construction of the Gannan major road is the rapid assembly of prefabricated parts and is also a construction difficulty. In China, similar construction projects are few, construction management experience is short, and no national standard can be referred to at present. The construction sequence in this project is drilling bored concrete pile foundation construction, cushion cap cast-in-place construction, prefabricated pier stud assembly, prefabricated crossbeam hoist and mount and prefabricated box girder hoist and mount in proper order. Therefore, the prefabricated parts have a large specific gravity, and how to complete the assembling task of the prefabricated parts quickly, efficiently, safely and high-quality becomes the control and decisive factor of the project. And in the process of prefabricating and assembling the pier stud, the capping beam and the box girder, the hoisting danger is high because the hoisting weight of the pier stud and the capping beam is large, and the temporary support of the prefabricated part must be considered emphatically. Because pier stud and bent cap are because of the difference of circuit requirement, the size is numerous. The temporary support of the prefabricated part is the core influencing the progress, safety, quality and economic benefit of the whole project on the basis of fully considering the existing materials on site and how to safely, economically, quickly, reasonably and efficiently finish the design and construction.
The embodiment of the invention mainly aims at monitoring and researching the C1 type bent cap temporary support of the fabricated bridge, and the technical scheme of the invention is also suitable for monitoring and researching the temporary supports of other types of bent caps, pier columns, box girders and the like.
Example 1
The temporary support form that this monitoring scheme adopted is the temporary support design form of C1 type standard bent cap, and C1 type standard bent cap is prefabricated bent cap, and the span is 24.7m, and the bent cap divide into two sections, and two prefabricated sections of each weigh 187.9 tons, and the design drawing is as shown in FIG. 1.
Sectional parameters of sectional materials of all members temporarily supported by the fabricated bridge are shown in figures 2-7.
(1) Establishing a model: and (3) using MIDAS/Civil software, and creating a support and beam model in the same proportion according to the actual construction layout condition, as shown in figures 8-10.
(2) Constraint and connection are applied: boundary condition constraints are applied to the model, and the constraints apply fixed constraints to the bottom end, as shown in fig. 11. And applying connection among the model longitudinal beams, the cross beams and the supports, wherein the connection is rigid connection in elastic connection.
(3) Applying a load
In the hoisting construction, the box girder is jointly borne by the bracket and the pier stud, the total weight of the box girder segments is distributed at each supporting point according to the node load situation, and the load applied to each supporting point is
In the wet joint construction, the weight of the poured concrete is shared by the support and the pier stud, the length of the wet joint of each two sections is 2m, and the wet joint is poured by 14.24m3Each fulcrum applying a load of
The first stage is as follows: and hoisting the left box girder as shown in fig. 12.
And a second stage: and hoisting the right box girder (the left box girder and the right box girder are not folded at the moment), as shown in fig. 13.
And a third stage: the left and right box girders are closed and wet joint construction is performed as shown in fig. 14.
(4) Force analysis
The combined stress analysis of the left box girder after the hoisting is finished in the first stage is shown in fig. 15:
the maximum combined compressive stress is 37.30MPa, the combined stress is less than 215MPa and is positioned on the upright post 1. The maximum compressive stress of the upright post 1 is 37.30Mpa and is positioned at the bottom support; the maximum compressive stress of the upright post 2 is 12.86Mpa and is positioned at the bottom support; the maximum compressive stress of the connecting system and the inclined strut is 17.76Mpa, the maximum tensile stress of the connecting system and the inclined strut is 10.75Mpa and the connecting system is arranged in the middle layer.
① joint of column 1 top and beam:
1)D＝426mm，d＝10mm，L＝2500mm，μ＝0.7；
2)l0＝0.7×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝56575cm4，Iy＝28287cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:meets the requirements.
② column 2 bottom bearing:
1)D＝426mm，d＝9mm，L＝2500mm，μ＝0.7；
2)l0＝μ×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝34920cm4，Iy＝17460cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:
meets the requirements.
③ bottom layer diagonal bracing:
1)L＝3536mm，μ＝0.5；
2)l0＝μ×l＝0.5×3536＝1768mm；A＝21.95cm2；
section moment of inertia: i isx＝866cm4，Iy＝73.40cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:
meets the requirements.
The schematic diagram of the displacement analysis of the left box girder after the hoisting is finished in the first stage is shown in fig. 16:
the maximum displacement is 1.36mm and is located in the stringer span. The maximum displacement of the upright post, the connecting system and the cross brace is 0.98mm, and the connecting system is positioned at the connecting part of the top end of the upright post 1 and the cross beam.
The combined stress analysis schematic diagram after the hoisting of the right box girder in the second stage is shown in fig. 17:
the maximum combined compressive stress is 34.10MPa and is positioned on the upright post 1, and the combined stress is less than 215 MPa. The maximum compressive stress of the upright column 1 is 34.10Mpa and is positioned at the bottom support; the maximum compressive stress of the upright post 2 is 22.89Mpa and is positioned at the bottom support; the maximum compressive stress of the connecting system and the inclined strut is 23.29Mpa, the maximum tensile stress of the connecting system and the inclined strut is 13.14Mpa and the connecting system is arranged in the middle layer.
① joint of column 1 top and beam:
1)D＝426mm，d＝10mm，L＝2500mm，μ＝0.7；
2)l0＝0.7×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝56575cm4，Iy＝28287cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:meets the requirements.
② column 2 bottom bearing:
1)D＝426mm，d＝9mm，L＝2500mm，μ＝0.7；
2)l0＝μ×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝34920cm4，Iy＝17460cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:
meets the requirements.
③ bottom layer diagonal bracing:
1)L＝3536mm，μ＝0.5；
2)l0＝μ×l＝0.5×3536＝1768mm；A＝21.95cm2；
section moment of inertia: i isx＝866cm4，Iy＝73.40cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:
meets the requirements.
The second stage right box girder hoisting completion displacement analysis schematic diagram is shown in fig. 18:
the maximum displacement is 1.04mm and is located in the stringer span. The maximum displacement of the upright post, the connecting system and the cross brace is 0.78mm, and the connecting system is positioned at the connecting part of the top end of the upright post 1 and the cross beam.
The third stage wet joint construction combined stress analysis schematic diagram is shown in fig. 19:
the maximum combined compressive stress is 37.22Mpa and is positioned at the bottom support of the upright post 1; the maximum compressive stress of the upright column 1 is 37.22Mpa and is positioned at the bottom support; the maximum compressive stress of the upright post 2 is 24.92Mpa and is positioned at the bottom support; the maximum compressive stress of the connecting system and the inclined strut is 25.51Mpa, the maximum tensile stress of the connecting system and the inclined strut is 14.35Mpa, and the connecting system is arranged in the middle layer connecting system.
① joint of column 1 top and beam:
1)D＝426mm，d＝10mm，L＝2500mm，μ＝0.7；
2)l0＝0.7×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝56575cm4，Iy＝28287cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:satisfy the requirement ofAnd (4) requiring.
② column 2 bottom bearing:
1)D＝426mm，d＝9mm，L＝2500mm，μ＝0.7；
2)l0＝μ×l＝0.7×2500＝1750mm；
section moment of inertia: i isx＝34920cm4，Iy＝17460cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:
meets the requirements.
③ bottom layer diagonal bracing:
1)L＝3536mm，μ＝0.5；
2)l0＝μ×l＝0.5×3536＝1768mm；A＝21.95cm2；
section moment of inertia: i isx＝866cm4，Iy＝73.40cm4；
Radius of gyration:
compliance (slenderness ratio) of the compression bar:
the requirements are met;
3) table look-up, stability factor:
allowable stress [ sigma ]]＝215MPa，
Critical stress:
maximum compressive stress:meets the requirements.
The third stage wet joint construction displacement analysis schematic is shown in fig. 20:
the maximum displacement is 1.01mm and is located in the stringer span. The maximum displacement of the upright post, the connecting system and the cross brace is 0.86mm, and the connecting system is positioned at the connecting part of the top end of the upright post 1 and the cross beam.
(5) Stability analysis: the model buckling mode 1 analysis schematic diagram is shown in fig. 21; the model buckling mode 2 analysis schematic diagram is shown in fig. 22; the model buckling mode 3 analysis schematic diagram is shown in fig. 23; the model buckling mode 4 analysis schematic diagram is shown in fig. 24; the model buckling mode 5 analysis schematic diagram is shown in fig. 25; the model buckling mode 6 analysis schematic diagram is shown in fig. 26; a schematic diagram of the results of the model buckling mode analysis calculation is shown in fig. 27. From fig. 21 to 27, the first-order numerical value 59 of the buckling analysis of the strut was calculated, and the structural stability satisfied the requirements. From the analysis results, the stress of the supporting structure member meets the requirements, the structural stability meets the requirements, but the critical load coefficient is small, potential safety hazards may exist in use, and therefore the temporary supporting system needs to be monitored during construction.
Example 2: construction inspection
(1) Monitoring content: the stress-strain sensor and the displacement sensor are arranged to monitor the main stressed part of the temporary support in the construction process, so that the safety and the stability in the construction scheme implementation process are ensured to meet the requirements of site construction.
(2) Testing an instrument: surface intelligent digital string type strain sensor: JMZX-212HAT (Tail decorated AT-intelligent memory temperature type) surface intelligent digital string type strain sensor. The sensor technology parameters are shown in table 1.
TABLE 1 technical parameters of intelligent digital string strain sensor
Differential pressure type static level: JMYC-6205AD, the level technical parameters are shown in 2. The differential pressure type static level testing system consists of a plurality of differential pressure type static level meters arranged at different measuring points, wherein one of the differential pressure type static level meters is arranged at a fixed point and is used as a reference point. The measuring point elements are connected in series and can be positioned at different elevations and different directions in the measuring range. And calculating the sedimentation change relative to the reference point by measuring the respective liquid level values of the measuring point sensor and the reference point sensor. The method is widely applicable to the precision measurement of various projects such as non-uniform settlement of road surfaces, non-linear settlement of profiles, dam settlement, bridge deflection, slope stability, building settlement and the like.
TABLE 2 technical parameters of differential pressure type static level
| Sensitivity of the probe | Accuracy of measurement | Size of | Measuring range |
| 0.1mm | 0.2％FS | 118mm (length) X118 mm (width) X69mm (height) | 5000mm |
A video projector: the video projector is associated with the mobile phone, and the whole process of the experiment is recorded.
(3) And (3) measuring point arrangement: and according to the finite element analysis result, monitoring point arrangement is carried out at the position of the most unfavorable dangerous point.
Stress strain measuring point arrangement: the stress-strain monitoring of the temporary support of the assembled bridge has eight measuring points which are respectively positioned at the bottom of the upright post 1, the bottom of the upright post 2 and the bottom of the bottom inclined strut, as shown in fig. 28.
Arranging displacement measuring points: the displacement monitoring of the temporary support of the assembled bridge has four measuring points which are respectively positioned at the joint of the longitudinal beam and the upright post 1, the mid-span position of the longitudinal beam and the joint of the longitudinal beam and the upright post 2, as shown in fig. 29.
(4) And (3) analyzing a monitoring result: according to the specific situation of site construction, GNc37 shafts are selected as monitoring objects, and a strain sensor and a static water level gauge are arranged on the support structure.
Stress strain monitoring result analysis
Sensor correlation calculation formula
A＝K1K2f2
1) Calculation formula of strain and frequency:
a-strain value, f-vibrating wire frequency, K(1)212＝0.00095106，K(2)212H＝2.5618。
σ＝Eε
2) Stress calculation
σ -stress; epsilon-strain
E-modulus of elasticity, Q235b Steel E ═ 2.01X 105Mpa；
And (3) analyzing a monitoring result: the stress-strain monitoring of the temporary support of the assembled bridge has eight measuring points which are respectively positioned at the bottom of the upright post 1, the bottom of the upright post 2 and the bottom inclined strut.
The experimental data change trend chart of the left side upright of the left bracket is shown in fig. 30 when the left box girder is hoisted, and the experimental data change trend chart of the left side upright of the left bracket is shown in fig. 31 when the right box girder is hoisted. As can be seen from the figure, the maximum tensile stress of the left upright post of the left bracket is 5.59MPa and the maximum compressive stress is 14.63MPa when the left box girder is hoisted, the maximum compressive stress is 14.63MPa after hoisting is finished, the finite element analysis result is 32.8MPa, and the data meet the requirements; the maximum compressive stress is 15.18MPa when the right box girder is hoisted, the compressive stress is 9.51MPa after hoisting is finished, the finite element analysis result is 30.4MPa, and the data meet the requirements.
The experimental data change trend chart of the left side stand of the left bracket is shown in fig. 32 when the left box girder is hoisted, and the experimental data change trend chart of the right side stand of the right bracket is shown in fig. 33 when the right box girder is hoisted. As can be seen from the figure, the maximum tensile stress of the upright column on the right side of the left bracket is 6.71MPa and the maximum compressive stress is 8.52MPa when the left box girder is hoisted, the maximum compressive stress is 8.52MPa after the hoisting is finished, the finite element analysis result is 9.5MPa, and the data meet the requirements; the maximum compressive stress is 8.22MPa when the right box girder is hoisted, the compressive stress is 7.62MPa after hoisting is finished, the finite element analysis result is 12.6MPa, and the data meet the requirements.
The experimental data change trend graph of the left side inclined strut of the left side bracket is shown in fig. 34 when the left side box girder is hoisted, the experimental data change trend graph of the left side inclined strut of the right side bracket is shown in fig. 35 when the right side box girder is hoisted, and the graph shows that the maximum tensile stress and the maximum compressive stress of the left side inclined strut of the left side bracket are respectively 3.84MPa and 3.34MPa when the left side box girder is hoisted, the compressive stress is 3.34MPa after hoisting is finished, the finite element analysis result is 6.8MPa, and the data meet the requirements; the maximum tensile stress is 5.51MPa and the maximum compressive stress is 3.18MPa when the right box girder is hoisted, the tensile stress is 3.84MPa after hoisting is finished, the finite element analysis result is 7.5MPa, and the data meet the requirements.
The experimental data change trend graph of the left side support right side inclined strut is shown in figure 36 when the left side box girder is hoisted, the experimental data change trend graph of the right side support right side inclined strut is shown in figure 37 when the right side box girder is hoisted, and it can be known from the graph that the maximum tensile stress of the left side support right side inclined strut is 6.73MPa when the left side box girder is hoisted, the maximum compressive stress is 11.62MPa, the compressive stress is 11.62MPa after hoisting is shown, the finite element analysis result is 12.8MPa, and the data meet the requirements; the maximum compressive stress is 12.22MPa when the right box girder is hoisted, the compressive stress is 11.01MPa after hoisting is finished, the finite element analysis result is 18.5MPa, and the data meet the requirements.
The experimental data change trend graph of the right side stand column of the right side bracket is shown in fig. 38 when the left box girder is hoisted, and the experimental data change trend graph of the right side stand column of the right side bracket is shown in fig. 39 when the right side box girder is hoisted, so that the maximum tensile stress of the right side stand column of the right side bracket is 5.73MPa when the left box girder is hoisted, the tensile stress is 5.73MPa after the hoisting is finished, and the finite element analysis result is 5.4MPa, because the finite element analysis result contains the stress generated by self weight and is 1.3MPa of compressive stress, the monitoring data meet the requirements; the maximum tensile stress is 5.73MPa and the maximum compressive stress is 27.12MPa when the right box girder is hoisted, the compressive stress is 18.41MPa after hoisting is finished, the finite element analysis result is 30.4MPa, and the data meet the requirements.
The experimental data change trend graph of the left upright of the right bracket is shown in figure 40 when the left box girder is hoisted, the experimental data change trend graph of the left upright of the right bracket is shown in figure 41 when the right box girder is hoisted, and the graph shows that the maximum tensile stress is 5.59MPa and the maximum compressive stress is 4.06MPa when the left box girder is hoisted, the compressive stress is 4.06MPa after hoisting is finished, the finite element analysis result is 7.3MPa, and the data meet the requirements; the maximum tensile stress is 0.76MPa and the maximum compressive stress is 5.27MPa when the right box girder is hoisted, the compressive stress is 3.76MPa after hoisting is finished, the finite element analysis result is 12.6MPa, and the data meet the requirements.
The experimental data change trend graph of the right side inclined strut of the right side support is shown in figure 42 when the left side box girder is hoisted, and the experimental data change trend graph of the right side inclined strut of the right side support is shown in figure 43 when the right side box girder is hoisted, so that the maximum tensile stress of the right side inclined strut of the right side support is 6.25MPa when the left side box girder is hoisted, the tensile stress is 6.25MPa after hoisting is finished, and the finite element analysis result is 4.3MPa, and because the finite element analysis result contains the stress generated by self weight and is 2MPa of compressive stress, the monitoring data can be regarded as meeting the requirements; the maximum tensile stress is 13.04MPa when the right box girder is hoisted, the tensile stress is 10.71MPa after hoisting is finished, and the finite element analysis result is 7.5MPa, and the monitoring data can be regarded as meeting the requirement because the finite element analysis result comprises the stress generated by self weight and is the compressive stress of 2 MPa.
The experimental data change trend graph of the left inclined strut of the right bracket is shown in fig. 44 when the left box girder is hoisted, and the experimental data change trend graph of the left inclined strut of the right bracket is shown in fig. 45 when the right box girder is hoisted, so that the maximum tensile stress and the maximum compressive stress of the left inclined strut of the right bracket are respectively 6.95MPa and 6.49MPa, the compressive stress is respectively 6.49MPa after hoisting is finished, and the finite element analysis result is 5.9MPa, and since the finite element analysis result contains the stress generated by self weight and is 1MPa of tensile stress, the monitoring data can be regarded as meeting the requirements; the maximum compressive stress is 25.21MPa when the right box girder is hoisted, the compressive stress is 21.81MPa after hoisting is finished, the finite element analysis result is 18.5MPa, and the data meet the requirements.
And (3) analyzing a displacement monitoring result: the assembled bridge temporary support displacement monitoring comprises four measuring points which are respectively located at the joint of the longitudinal beam and the upright post 1, the mid-span position of the longitudinal beam and the joint of the longitudinal beam and the upright post 2.
Fig. 46 is a trend graph of experimental data change of the mid-span position of the longitudinal beam when the left box girder is hoisted, and fig. 47 is a trend graph of experimental data change of the mid-span position of the longitudinal beam when the right box girder is hoisted. The diagram shows that the maximum displacement of the middle position of the longitudinal beam span is 0.43mm when the left box girder is hoisted, the displacement is 0.23mm after hoisting is finished, the finite element analysis result is 1.36mm, and the data meet the requirements; the maximum displacement is 0.67mm when the right box girder is hoisted, the displacement is 0.67mm after hoisting is finished, the finite element analysis result is 1.04mm, and the data meet the requirements.
Fig. 48 is a graph showing experimental data change trend at the joint of the left side support longitudinal beam and the upright 1 when the left side box beam is hoisted, and fig. 49 is a graph showing experimental data change trend at the joint of the left side support longitudinal beam and the upright 1 when the right side box beam is hoisted. As can be seen from the figure, the maximum displacement of the joint between the left bracket longitudinal beam and the upright post 1 when the left box girder is hoisted is 0.15mm, the displacement after hoisting is 0.11mm, the finite element analysis result is 0.69mm, and the data meet the requirements; the maximum displacement is 0.08mm when the right box girder is hoisted, the displacement is 0.01mm after hoisting is finished, the finite element analysis result is 0.78mm, and the data meet the requirements.
Fig. 50 is a graph showing the trend of experimental data change at the joint between the right side support longitudinal beam and the upright 1 when the left side box girder is hoisted, and fig. 51 is a graph showing the trend of experimental data change at the joint between the right side support longitudinal beam and the upright 1 when the right side box girder is hoisted. As can be seen from the figure, the maximum displacement of the joint between the right side support longitudinal beam and the upright post 1 when the left side box girder is hoisted is 0.67mm, the displacement after hoisting is 0.32mm, the finite element analysis result is 0.44mm, and the data meet the requirements; the maximum displacement is 0.54mm when the right box girder is hoisted, the displacement is 0.19mm after hoisting is finished, the finite element analysis result is 0.78mm, and the data meet the requirements.
Fig. 52 is a graph showing the trend of experimental data at the joint between the right side support longitudinal beam and the upright 2 when the left side box beam is hoisted, and fig. 53 is a graph showing the trend of experimental data at the joint between the right side support longitudinal beam and the upright 2 when the right side box beam is hoisted. As can be seen from the figure, the maximum displacement of the joint between the right side support longitudinal beam and the upright post 2 when the left side box girder is hoisted is 0.68mm, the displacement is 0.28mm after hoisting is finished, the finite element analysis result is 0.45mm, and the data meet the requirements; the maximum displacement is 0.42mm when the right box girder is hoisted, the displacement is 0.26mm after hoisting is finished, the finite element analysis result is 0.21mm, and the data meet the requirements.
Stress and strain monitoring experiments and displacement deformation monitoring experiments are carried out on the whole box girder hoisting process, comparison analysis is carried out on experimental results and finite element analysis and calculation results, stress and displacement of the main stress member for temporary support in the box girder hoisting construction process can be within a limit value range, and the designed temporary support has reliable safety.
Through further analysis of the calculation results, it is found that: allowable stress of column
The maximum compressive stress in construction obtained in the finite element calculation simulation construction process is 37.22MPa, the actual maximum compressive stress in the box girder hoisting process is 27.12MPa, the utilization rate is only 13%, and the waste of steel is high; allowable stress of diagonal brace
The maximum compressive stress in construction is 25.51MPa, the actual maximum compressive stress in the box girder hoisting process is 25.21MPa, the utilization rate is 59%, and the set 80% secondary early warning is approached. Therefore, the design of the bracket can be improved to a certain extent, for example, the size of the upright column is reduced in a proper amount, the utilization rate of steel is improved, the cross section of the connecting system rod piece is changed into a circular tube and other forms, and the structural stress is more reasonable.
Example 3: temporary support construction monitoring system
(1) Introduction of the platform: the support monitoring platform is convenient for data management, is designed through data processing and analysis, and an experiment responsible person installs a support sensor and associates a BIM model, and then obtains the maximum bearing value of each measuring point through finite element calculation and analysis and inputs the maximum bearing value into the platform. And in the monitoring process, the stability condition of the on-site support can be checked on the platform, and if the stability condition exceeds the early warning range, the early warning system gives an alarm and sends a warning short message to an early warning pusher. After the early warning is pushed, detailed information is checked in the platform and is managed by different types of sensors, the information can be visually displayed in the model, and a project responsible person can quickly and simply check the data of the current sensor and the support supporting condition of a field. The management is convenient, the data is updated in real time, and the data analysis is better performed by project responsible persons.
(2) Platform function
1. Brief introduction of items: propagandizing and displaying project data and introducing project background.
2. User registration and login: the method comprises the steps of system user login, user registration, user basic information modification, user role management and access authority setting.
3. Instrument panel: the summary page of various data can be used for checking the current monitoring information, early warning state and support model
4. Sensor management: when the detection data needs to be collected, experimenters need to define the numbers and other information of the sensors in the system and bind the positions of the sensors in the model, so that the sensors in the system can be summarized. Experimenters can conveniently find the corresponding sensors through categories and numbers.
5. Data management: after the experimental content is determined, the sensor is built on the site, the sensor uploads data to the platform through a wireless network, and the platform automatically records the data of the sensor and analyzes the current data early warning condition. The data of the sensor can be viewed in different user login platforms, and can be exported and saved locally for experimental result analysis.
6. And (3) model display: the data of the current experiment are displayed in a model and line graph mode, and the method is more visual.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (6)
1. A safety monitoring method for an assembled bridge support is characterized by comprising the following steps:
(1) establishing a temporary support rod piece model of the prefabricated part by using a BIM technology, designing relevant parameters of the rod piece and relevant parameters of the prefabricated part, and summarizing the models to form a temporary support model library;
(2) establishing a finite element model for the whole construction process of the assembled bridge support by using MIDAS/Civil to analyze the mechanical behavior of the whole construction process;
(3) according to the finite element calculation result, arranging a test instrument, carrying out stress monitoring and displacement monitoring on a main stressed part in the construction process, comparing the monitoring result with the finite element analysis, and verifying the safety of the construction scheme;
(4) a temporary support safety monitoring system is built, a BIM model is combined, a wireless sensing system is in butt joint with a monitoring system platform, a monitoring position corresponding to a field sensor is found in the model, and the stress and the displacement of the support are recorded in real time in the construction process.
2. The method of claim 1, wherein the fabricated bridge bracket is a fabricated bridge deck temporary support.
3. A method according to claim 2, wherein the capping beam is a C1 type capping beam.
4. The method of claim 1, wherein the parameters associated with the rod member include one or more of a code, a manufacturer, a mechanical property, a material, an inventory, and a price.
5. The method according to claim 1 or 4, wherein the relevant parameters of the prefabricated parts comprise one or several of factory time, dimensions, materials, mechanical properties and coding.
6. The method of claim 1, wherein the temporary support security monitoring system comprises a login module, a stent support model library module, a sensor management module, a data management module, and a model data presentation module.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113700028A (en) * | 2021-08-27 | 2021-11-26 | 上海市基础工程集团有限公司 | Movable reusable support foundation structure for mounting prefabricated parts of viaduct bridge |
| CN115981255A (en) * | 2022-12-12 | 2023-04-18 | 江苏丰华建筑系统集成有限公司 | Performance monitoring method and system of steel structure test platform |
| CN116339224A (en) * | 2023-02-14 | 2023-06-27 | 深圳市曜麒科技有限公司 | Jacking operation monitoring system and control method for single-pier bridge reinforcing device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106354968A (en) * | 2016-09-14 | 2017-01-25 | 铁道第三勘察设计院集团有限公司 | Pre-stressed continuous concrete beam design method based on BIM technology |
| CN108301328A (en) * | 2018-02-01 | 2018-07-20 | 广州市恒盛建设工程有限公司 | One kind getting higher change and indulges horizontal curve steel box girder construction method |
| CN108537463A (en) * | 2018-04-20 | 2018-09-14 | 中铁四局集团第三建设有限公司 | Cast-in-situ bridge support system construction monitoring system and method based on BIM |
-
2019
- 2019-09-12 CN CN201910889473.4A patent/CN110672150A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106354968A (en) * | 2016-09-14 | 2017-01-25 | 铁道第三勘察设计院集团有限公司 | Pre-stressed continuous concrete beam design method based on BIM technology |
| CN108301328A (en) * | 2018-02-01 | 2018-07-20 | 广州市恒盛建设工程有限公司 | One kind getting higher change and indulges horizontal curve steel box girder construction method |
| CN108537463A (en) * | 2018-04-20 | 2018-09-14 | 中铁四局集团第三建设有限公司 | Cast-in-situ bridge support system construction monitoring system and method based on BIM |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113700028A (en) * | 2021-08-27 | 2021-11-26 | 上海市基础工程集团有限公司 | Movable reusable support foundation structure for mounting prefabricated parts of viaduct bridge |
| CN115981255A (en) * | 2022-12-12 | 2023-04-18 | 江苏丰华建筑系统集成有限公司 | Performance monitoring method and system of steel structure test platform |
| CN115981255B (en) * | 2022-12-12 | 2023-12-15 | 扬州丰筑建设工程有限公司 | Performance monitoring method and system for steel structure test platform |
| CN116339224A (en) * | 2023-02-14 | 2023-06-27 | 深圳市曜麒科技有限公司 | Jacking operation monitoring system and control method for single-pier bridge reinforcing device |
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