A construction method for high-pier continuous rigid frame bridge

Abstract

The present invention provides a construction method for a high-pier continuous rigid frame bridge, which relates to the technical field of bridge construction and comprises the following steps: step 1: collecting various BIM components of the bridge, constructing a database, and selecting bridge components of a scheme according to construction needs; step 2: discretizing each main beam into beam units, regarding the three pier bottoms as consolidation, and the span ends on both sides as chain rod supports, and inputting the unit geometric information and data of each construction stage into the bridge components; step 3: using finite element software to perform construction simulation calculations, and determining the design linear shape, target linear shape and pre-camber linear shape of the box beam; the present invention constructs a box beam formwork elevation model, and during stage construction, stakes out the formwork elevation. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation to ensure control of the structure during the bridge construction process.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge construction, in particular to a construction method of a high-pier continuous rigid frame bridge. Background Art

[0002] A continuous rigid frame bridge is a continuous beam bridge with fixed piers and beams. It is one of the most commonly used forms of long-span bridges developed on the basis of continuous beam bridges and T-shaped rigid frame bridges. It has the characteristics of large spanning capacity, comfortable driving, and no need for large supports. This type of bridge is particularly suitable for crossing deep valleys, large rivers, and rapids. Since this year, the number of high-pier and long-span bridges built across mountainous and hilly areas and between steep slopes and deep valleys has increased in transportation construction, bringing new opportunities for the development of high-pier and long-span continuous rigid frame bridges. At the same time, how to effectively improve the construction control level of such bridges, ensure the safety and stability of the structure, ensure the reasonable force of the structure and the smooth linear shape, and provide technical support for the safe and smooth construction of the bridge is an issue that requires special attention during construction.

[0003] In the prior art, application number CN 112030772A discloses a "rapid construction method for a continuous rigid frame bridge," and specifically discloses: the use of a single-pile, single-column lower structure system reduces the impact of environmental factors on construction; the use of processes such as whole-hole segment assembly and secondary pouring of the pier top reduces material usage and construction costs; and because the prestressed tendons are stretched after the secondary pouring of the pier top, the waiting time of the bridge erection machine is reduced, speeding up the construction progress. However, the continuous rigid frame system is subject to gradual changes in the number of structural units and loads during construction, making it a complex, indeterminate structure. The above-mentioned technology lacks control over the deformation and stress conditions of the structure during construction, and also lacks simulation of external factors. Therefore, the present invention proposes a construction method for a high-pier continuous rigid frame bridge to solve the problems existing in the prior art. Summary of the Invention

[0004] In response to the above problems, the present invention proposes a method for constructing a high-pier continuous rigid frame bridge. The method for constructing a high-pier continuous rigid frame bridge grasps the actual deformation law, controls the bridge by adjusting the formwork elevation, and ensures control of the structure during the bridge construction process.

[0005] To achieve the purpose of the present invention, the present invention is implemented through the following technical solutions: A method for constructing a high-pier continuous rigid frame bridge comprises the following steps:

[0006] Step 1: Collect various BIM components of the bridge, build a database, and select the bridge components of the scheme according to construction needs;

[0007] Step 2: Discretize each main beam into beam elements, consider the three pier bottoms as consolidated, and the two span ends as chain rod supports. Input the unit geometry information and data of each construction stage into the bridge components;

[0008] Step 3: Use finite element software to perform construction simulation calculations to determine the box girder design line shape, target line shape, and pre-camber line shape. Use the pre-camber curve to construct the box girder formwork elevation model. In the later stage of construction, the formwork elevation will be set out.

[0009] Step 4: Establish a wind speed simulation, apply wind pressure to the bridge model from multiple directions and multiple levels of wind force, determine the stress conditions of each structural surface of the bridge, and determine the reinforcement points;

[0010] Step 5: Use flip formwork to construct high piers, and control the verticality and appearance quality of the pier during construction;

[0011] Step 6: Use cables to assemble the hanging basket. After the hanging basket is installed, simulate preloading is carried out, and then the steel bars and pipes are installed. Then, concrete is poured in the bottom plate, web plate, and top plate in sequence.

[0012] Step 7: Using a three-way prestressing system, the total prestressing order is: first tension the longitudinal prestressing steel strands, then tension the transverse prestressing steel strands, and finally tension the vertical prestressing coarse steel bars;

[0013] Step 8: After the pouring of the previous section is completed, the concrete reaches the design strength requirements, and the prestressed steel strands and steel bars are tensioned, the hanging basket is moved to proceed to the construction of the next section;

[0014] Step 9: For each box girder cantilever, measure the deflection after the hanging basket moves, the segment concrete is poured, and before and after the prestressed tendons are tensioned.

[0015] A further improvement is that in step 1, in the database, all BIM components of the bridge are modules with 3M as the base module, and the bridge components of the selected scheme are presented in the form of models in the BIM application.

[0016] A further improvement is that in step 2, the data of each construction stage includes load, creep, shrinkage, and prestressing information.

[0017] Further improvements are: in step 3, the finite element software MIDAS / Civil is used to perform construction simulation calculations, and in step 3, the pre-camber curve is used to construct the box girder formwork elevation model:

[0018] H i 立模 =H i 设计 +f i 1 / 2静活载 +f i 后期徐变 +F i 竣工

[0019] Where: H i 立模 - Formwork elevation of stage i;

[0020] H i 设计 - The design elevation of Phase I shall be provided by the designer;

[0021] f i 1 / 2静活载 -Deformation caused by the bridge bearing 1 / 2 of the static and live loads;

[0022] f i 后期徐变 -The deformation of the bridge after completion due to the late creep of concrete is obtained through structural calculation;

[0023] F i 竣工 - After the formwork is erected, a certain point in the structure may be deformed due to subsequent construction operations. This deformation will not occur until the bridge is completed;

[0024] During the later stages of construction, the formwork elevation is set out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation.

[0025] Further improvements are as follows: in step four, a wind speed simulation is established, first obtaining a wind cloud map at the location where the bridge is to be built, performing a wind pressure test on the bridge model, then simulating wind from areas not covered by the wind cloud map, performing a wind pressure test on the bridge model, judging the stress conditions of each structural surface of the bridge, and determining reinforcement points.

[0026] Further improvements are as follows: in the step five, a flip formwork is used for high pier construction, and cables are used to cast concrete and install the formwork. Specifically, at least four sets of flip formwork are invested in the construction of thin-walled piers, and each set of flip formwork consists of two groups of formworks. The pier column is constructed for the first time with Xm segments cast at one time, and thereafter it is a cycle of Ym. After each concrete pouring is completed, the lower set of formwork is flipped and installed, and the uppermost set of formwork is retained as the load-bearing support structure of the flip formwork. Each installation of the rigid frame, steel bars, formwork and pouring of concrete is considered a construction cycle.

[0027] Further improvements are: in the step six, the hanging basket is assembled by using a cable hoist, first the main truss is assembled in place on the cast beam section, then the bottom basket is assembled, and it is lifted and hung in place by a winch, and finally the lifting system, anchoring system, and walking system are installed. After the hanging basket is installed, a simulated pre-stressing is performed to verify the stability of the hanging basket, and the elastic deformation and inelastic deformation of the hanging basket are obtained. The pre-stressing load is 115% of the deadweight of the heaviest beam section. Before pre-stressing, two observation points are built on the front upper crossbeam and the bottom template of each hanging basket, painted, and observed during the pre-stressing process, and the calculation of each stage is also carried out. The difference between the actual settlement and the theoretical settlement is less than 10 mm, which is the predicted inelastic deformation. In step six, concrete is poured in the bottom plate, web plate and top plate in sequence. The web plate can be poured only after the bottom plate concrete has initially set. The web plate pouring sequence is: first pour the front end of the segment, then pour the rear end of the segment, and finally pour from both ends to the middle. The horizontal layering method is used for pouring, and the whole is poured into shape at one time. After the concrete pouring is completed, it is covered with felt and watered in time for maintenance. After the concrete at the end of the segment reaches the design strength, it is roughened and cleaned.

[0028] A further improvement is that in step seven, after the concrete strength reaches 90% of the design strength and the concrete age is not less than 7 days, prestressed construction is carried out, and the prestressed steel strands are tensioned once. After the longitudinal and transverse tensioning are completed, the steel strands are cut with a grinding wheel machine, and the length of the exposed steel strands outside the anchor ring is controlled to be greater than 3-5 cm, and then the anchor is sealed.

[0029] Further improvements are: in the step eight, the hanging basket moving steps: remove the inner formwork system and the side formwork system; remove the bottom film system; remove the pads, lay them to the front box girder, and move the guide slide to the front box girder; anchor the slide; the hanging basket main truss system moves forward, and drives the side formwork system, the inner formwork system and the bottom formwork system to move forward together; the hanging basket is in place, anchoring the main truss; lifting the bottom formwork system; lifting the side formwork system; lifting the inner formwork system; preparing for the next section construction.

[0030] A further improvement is that in step nine, during stage construction, when staking out the formwork elevation, the time when the temperature is stable is selected.

[0031] The beneficial effects of the present invention are:

[0032] 1. The present invention constructs a box girder formwork elevation model. During stage construction, the formwork elevation is set out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation to ensure control of the structure during the bridge construction process.

[0033] 2. The present invention measures the deflection of each box girder cantilever after the hanging basket moves, the segment concrete is poured, before the prestressed tendons are tensioned, and after the prestressed tendons are tensioned, so as to grasp the key stages of construction control and meet the control of construction stress.

[0034] 3. The present invention is based on BIM application and establishes wind speed simulation. It applies wind pressure to the bridge model after construction from multiple directions and multiple levels of wind force, judges the stress conditions of each structural surface of the bridge, and determines the reinforcement points, which is conducive to improving the reliability of subsequent construction.

[0035] 4. During construction, the present invention simulates prestressing of the hanging basket installation to verify the stability of the hanging basket, adopts a three-way prestressing system, controls the total prestressing tensioning sequence, and controls the strength requirements of the concrete, making the construction safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Flowchart of the present invention. DETAILED DESCRIPTION

[0037] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the examples. The examples are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0038] Example 1

[0039] according to Figure 1 As shown, this embodiment proposes a method for constructing a high-pier continuous rigid frame bridge, comprising the following steps:

[0040] Step 1: Collect various BIM components of the bridge, build a database, and select the bridge components of the scheme according to construction needs;

[0041] Step 2: Discretize each main beam into beam elements, consider the three pier bottoms as consolidated, and the two span ends as chain rod supports. Input the unit geometry information and data of each construction stage into the bridge components;

[0042] Step 3: Use finite element software to perform construction simulation calculations to determine the box girder design line shape, target line shape, and pre-camber line shape. Use the pre-camber curve to construct the box girder formwork elevation model. In the later stage of construction, the formwork elevation will be set out.

[0043] Step 4: Establish a wind speed simulation, apply wind pressure to the bridge model from multiple directions and multiple levels of wind force, determine the stress conditions of each structural surface of the bridge, and determine the reinforcement points;

[0044] Step 5: Use flip formwork to construct high piers, and control the verticality and appearance quality of the pier during construction;

[0045] Step 6: Use cables to assemble the hanging basket. After the hanging basket is installed, simulate preloading is carried out, and then the steel bars and pipes are installed. Then, concrete is poured in the bottom plate, web plate, and top plate in sequence.

[0046] Step 7: Using a three-way prestressing system, the total prestressing order is: first tension the longitudinal prestressing steel strands, then tension the transverse prestressing steel strands, and finally tension the vertical prestressing coarse steel bars;

[0047] Step 8: After the pouring of the previous section is completed, the concrete reaches the design strength requirements, and the prestressed steel strands and steel bars are tensioned, the hanging basket is moved to proceed to the construction of the next section;

[0048] Step 9: For each box girder cantilever, measure the deflection after the hanging basket moves, the segment concrete is poured, and before and after the prestressed tendons are tensioned.

[0049] The present invention constructs a box girder formwork elevation model. During stage construction, the formwork elevation is set out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation to ensure control of the structure during the bridge construction process.

[0050] Example 2

[0051] according to Figure 1 As shown, this embodiment proposes a method for constructing a high-pier continuous rigid frame bridge, comprising the following steps:

[0052] Collect various BIM components of bridges and build a database. In the database, various BIM components of bridges are modules with 3M as the base module. According to construction needs, the bridge components of the scheme are selected and displayed in the form of models in the BIM application;

[0053] Each main beam is discretized into beam units, the three pier bottoms are considered to be consolidated, and the two span ends are considered to be chain rod supports. The unit geometry information and data of each construction stage, including load, creep, shrinkage, and prestressing information, are input into the bridge components; this makes it easy to simulate the bridge components as models of each unit, thereby facilitating patchwork construction and construction simulation.

[0054] Finite element software MIDAS / Civil was used to perform construction simulation calculations to determine the design, target, and pre-camber alignments of the box girder. The pre-camber curve was then used to construct a model of the box girder formwork elevation. In the later stages of construction, the formwork elevation was set out, and the pre-camber curve was used to construct a model of the box girder formwork elevation:

[0055] H i 立模 =H i 设计 +fi 1 / 2静活载 +f i 后期徐变 +F i 竣工

[0056] Where: H i 立模 - Formwork elevation of stage i;

[0057] H i 设计 - The design elevation of Phase I shall be provided by the designer;

[0058] f i 1 / 2静活载 -Deformation caused by the bridge bearing 1 / 2 of the static and live loads;

[0059] f i 后期徐变 -The deformation of the bridge after completion due to the late creep of concrete is obtained through structural calculation;

[0060] F i 竣工 - After the formwork is erected, a certain point in the structure will be deformed due to subsequent construction operations, and this deformation will not occur until the bridge is completed.

[0061] During the later stages of construction, the formwork elevation is laid out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation. The present invention constructs a box girder formwork elevation model. During the stage construction, the formwork elevation is laid out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation, thereby ensuring control over the structure during the bridge construction process.

[0062] To establish a wind speed simulation, first obtain a wind cloud map at the location where the bridge is to be built, perform a wind pressure test on the bridge model, then simulate wind from the area not covered by the wind cloud map, perform a wind pressure test on the bridge model, apply wind pressure to the bridge model after construction from multiple directions and multiple levels of wind, judge the stress conditions of each structural surface of the bridge, and determine the reinforcement points; the present invention is based on BIM application, establishes a wind speed simulation, applies wind pressure to the bridge model after construction from multiple directions and multiple levels of wind, judges the stress conditions of each structural surface of the bridge, and determines the reinforcement points, which is conducive to improving the reliability of subsequent construction.

[0063] The flip formwork is used for high pier construction, and the concrete is poured and the formwork is installed by cable hoisting. Specifically, at least four sets of flip formwork are used for the construction of thin-walled piers. Each set of flip formwork consists of two groups of formwork. The pier column is first constructed to cast Xm segments at one time, and then it is a cycle of Ym. After each concrete pouring, the lower set of formwork is flipped and installed, and the top set of formwork is retained as the load-bearing support structure of the flip formwork. Each installation of the rigid skeleton, steel bars, formwork and pouring of concrete is a construction cycle. The verticality and appearance quality of the pier body are controlled during the construction process. In actual application, 4 sets of flip formwork are used for the construction of thin-walled piers. Each set of flip formwork consists of two groups of formwork. The height of each group of formwork is 2.0m. The pier column is first constructed to cast 4m at a time. Each section is constructed in a 2m cycle. After each concrete pouring, the lower set of 2m formwork is flipped and installed, and the uppermost set of 2m formwork is retained as the load-bearing support structure for the flipping formwork. The average construction cycle of the main bridge pier is 3 days per 2m height, that is, each installation of the rigid frame, steel bars, formwork and pouring of concrete is a cycle. Basically, a construction cycle is 3 days. To ensure an average construction of 0.7 meters per day, considering other unforeseen factors, the construction time of the 72-meter pier is 120 days. Concrete is hoisted by cable hoisting, with an average hoisting capacity of 7m 3 / h.

[0064] The hanging basket is assembled by using cables. First, the main truss is assembled in place on the cast beam section, and then the bottom basket is assembled. It is lifted and hung in place by a winch. Finally, the lifting system, anchoring system, and walking system are installed. After the hanging basket is installed, a simulated pre-stressing is carried out to verify the stability of the hanging basket. The elastic deformation and inelastic deformation of the hanging basket are obtained. The pre-stressing load is 115% of the deadweight of the heaviest beam section. Before pre-stressing, two observation points are built on the front upper crossbeam and the bottom template of each hanging basket, and painted. Observations are carried out during the pre-stressing process, and the theoretical settlement of each stage is calculated. The difference between the actual settlement and the theoretical settlement is also calculated. The value is less than 10mm, which is the predicted inelastic deformation. Then the steel bars and pipes are installed, and then the concrete is poured in the bottom plate, web plate and top plate in sequence. The web plate can be poured only after the bottom plate concrete has initially set. The web plate pouring order is: first pour the front end of the segment, then pour the rear end of the segment, and finally pour from both ends to the middle. The horizontal layered method is adopted for pouring, and the whole is cast in one time. After the concrete pouring is completed, it is covered with felt and watered in time for maintenance. After the concrete at the end of the segment reaches the design strength, it is roughened and cleaned. Practical application: The dead weight of the hanging basket (including the formwork) shall not be greater than 0.4 times the maximum beam segment. Therefore, when selecting the hanging basket form, a triangular hanging basket with a light structure and reasonable force is selected. The rods basically use large-section steel to ensure the rigidity of the hanging basket. During the preloading process, the measurement personnel should observe closely. If any abnormal phenomenon is found, the preloading should be stopped immediately to find the cause.

[0065] A three-way prestressed system is adopted, and the total prestressing tensioning sequence is: first tension the longitudinal prestressed steel strands, then tension the transverse prestressed steel strands, and finally tension the vertical prestressed coarse steel bars; specifically: after the concrete strength reaches 90% of the design strength and the concrete age is not less than 7d, prestressing construction is carried out, and the prestressed steel strands adopt a one-time tensioning process, wherein, after the longitudinal and transverse tensioning are completed, the steel strands are cut with a grinding wheel machine, and the length of the exposed steel strands of the anchor ring is controlled to be greater than 3-5cm, and then the anchor is sealed; the pouring process of the concrete at the sealed anchor end is: installing the steel mesh, fixing the formwork, pouring concrete, removing the formwork, and curing.

[0066] After the previous section is poured and the concrete reaches the design strength requirements, and the prestressed steel strands and steel bars are tensioned, the hanging basket is moved. The steps are as follows: remove the inner formwork system and the side formwork system; remove the bottom membrane system; remove the pads and lay them to the front box girder, and move the guide slide to the front box girder; anchor the slide; move the main girder system of the hanging basket forward, and drive the side formwork system, the inner formwork system and the bottom formwork system forward together; the hanging basket is in place and the main girder is anchored; lift the bottom formwork system; lift the side formwork system; lift the inner formwork system; and prepare for the construction of the next section.

[0067] For each box girder cantilever, deflection measurements are taken after the gantry is moved, after the segment concrete is poured, and before and after the prestressing tendons are tensioned. Simultaneously, during staged construction, when setting out the formwork elevation, measurements are taken at a time when the temperature is stable. Temperature is the primary factor influencing measured data, so research into the effects of temperature changes on elevation alignment is essential. Since the temperature field is constantly changing, accurately calculating the impact of temperature is nearly impossible. To minimize the impact of temperature changes on elevation alignment, when establishing the formwork elevation during the box girder construction phase, measurements should be taken at a time when the temperature is relatively stable and the impact is minimal.

[0068] The present invention constructs a box girder formwork elevation model. During staged construction, the formwork elevation is set out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation to ensure control of the structure during the bridge construction process. In addition, the present invention measures the deflection of each box girder cantilever after the hanging basket moves, the segment concrete is poured, before the prestressed tendons are tensioned, and after the prestressed tendons are tensioned, so as to grasp the key stages of construction control and meet the control of construction stress. At the same time, the present invention is based on BIM application to establish a wind speed simulation, and applies wind pressure to the model after the bridge construction from multiple directions and multiple levels of wind force to judge the stress conditions of each structural surface of the bridge and determine the reinforcement points, which is conducive to improving the reliability of subsequent construction. In addition, after the hanging basket is installed, the present invention performs simulated prestressing to verify the stability of the hanging basket, obtain the elastic deformation and inelastic deformation of the hanging basket, adopts a three-way prestressing system, controls the total prestressing tensioning sequence, and controls the strength requirements of the concrete, so that the construction is safe and reliable.

[0069] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for constructing a high-pier continuous rigid frame bridge, characterized in that: The following steps are involved: Step 1: Collect various BIM components of the bridge, build a database, and select the bridge components of the scheme according to construction needs; Step 2: Discretize each main beam into beam elements, consider the three pier bottoms as consolidated, and the two span ends as chain rod supports. Input the unit geometry information and data of each construction stage into the bridge components; Step 3: Use finite element software to perform construction simulation calculations to determine the box girder design line shape, target line shape, and pre-camber line shape. Use the pre-camber curve to construct the box girder formwork elevation model. In the later stage of construction, the formwork elevation will be set out. Step 4: Establish a wind speed simulation, apply wind pressure to the bridge model from multiple directions and multiple wind speeds, determine the stress conditions of each structural surface of the bridge, and determine the reinforcement points; Step 5: Use flip formwork to construct high piers, and control the verticality and appearance quality of the pier body during construction. In the step 5, use flip formwork to construct high piers, use cable hanging to pour concrete and install formwork, specifically: invest in at least four sets of flip formwork for the construction of thin-walled piers, each set of flip formwork consists of two groups of formwork, the pier column is first constructed to pour Xm segments at a time, and thereafter it is a cycle of Ym, each time concrete pouring is completed, the lower set of formwork is flipped and installed, and the uppermost set of formwork is retained as the load-bearing support structure of the flip formwork, and each installation of the rigid skeleton, steel bars, formwork and pouring of concrete is considered a construction cycle; Step 6: Use cables to assemble the hanging basket. After the hanging basket is installed, simulate preloading is carried out, and then the steel bars and pipes are installed. Then, concrete is poured in the bottom plate, web plate, and top plate in sequence. Step 7: Using a three-way prestressing system, the total prestressing order is: first tension the longitudinal prestressing steel strands, then tension the transverse prestressing steel strands, and finally tension the vertical prestressing coarse steel bars; Step 8: After the pouring of the previous section is completed, the concrete reaches the design strength requirements, and the prestressed steel strands and steel bars are tensioned, the hanging basket is moved to proceed to the construction of the next section; Step 9: For each box girder cantilever, measure the deflection after the hanging basket moves, the segment concrete is poured, and before and after the prestressed tendons are tensioned.

2. The method for constructing a high-pier continuous rigid frame bridge according to claim 1, characterized in that: In the step 1, in the database, all BIM components of the bridge are modules based on 3M as the base module, and the bridge components of the selected scheme are presented in the form of models in the BIM application.

3. The method for constructing a high-pier continuous rigid frame bridge according to claim 1, characterized in that: In step 2, the data of each construction stage includes load, creep, shrinkage, and prestressing information.

4. The method for constructing a high-pier continuous rigid frame bridge according to claim 1, characterized in that: In the step 3, the finite element software MIDAS / Civil is used to perform construction simulation calculations, and in the step 3, the pre-camber curve is used to construct the box girder formwork elevation model: H i 立模 =H i 设计 +f i 1 / 2静活载 +f i 后期徐变 +F i 竣工 Where: H i 立模 - Formwork elevation of stage i; H i 设计 - The design elevation of Phase I shall be provided by the designer; f i 1 / 2静活载 -Deformation caused by the bridge bearing 1 / 2 of the static and live loads; f i 后期徐变 -The deformation of the bridge after completion due to the late creep of concrete is obtained through structural calculation; F i 竣工 - After the formwork is erected, a certain point in the structure may be deformed due to subsequent construction operations. This deformation will not occur until the bridge is completed; During the later stages of construction, the formwork elevation is set out. When the measured deformation does not match the theoretical calculated value, the calculation parameters are adjusted, the theoretical model is corrected, the deviation between theory and practice is eliminated, the law of actual deformation is mastered, and the bridge is controlled by adjusting the formwork elevation.

5. The method for constructing a high-pier continuous rigid frame bridge according to claim 1, characterized in that: In the fourth step, a wind speed simulation is established. First, a wind cloud map is obtained at the location where the bridge is to be built, and a wind pressure test is performed on the bridge model. Then, wind force is simulated in the area not covered by the wind cloud map, and a wind pressure test is performed on the bridge model to determine the stress conditions of each structural surface of the bridge and determine the reinforcement points.

6. The method for constructing a high-pier continuous rigid frame bridge according to claim 1, characterized in that: In the step six, the hanging basket is assembled by using a cable hoist. First, the main truss is assembled in place on the cast beam section, and then the bottom basket is assembled. It is lifted and hung in place by a winch. Finally, the lifting system, anchoring system, and walking system are installed. After the hanging basket is installed, a simulated pre-stressing is performed to verify the stability of the hanging basket. The elastic deformation and inelastic deformation of the hanging basket are obtained. The pre-stressing load is 115% of the deadweight of the heaviest beam section. Before pre-stressing, two observation points are built on the front upper crossbeam and the bottom template of each hanging basket, and painted. Observations are carried out during the pre-stressing process, and the calculation of each level is also carried out. The theoretical settlement of the segment, the difference between the actual settlement and the theoretical settlement is less than 10mm, and in step six, the concrete is poured in sequence in the bottom plate, web plate and top plate. The web plate can be poured only after the bottom plate concrete has initially set. The pouring order of the web plate is: first pour the front end of the segment, then pour the rear end of the segment, and finally pour from both ends to the middle. The horizontal layered method is used for pouring, and the whole is poured into shape at one time. After the concrete is poured, it is covered with felt and watered in time for maintenance. After the concrete at the end of the segment reaches the design strength, it is roughened and cleaned.

7. The method for constructing a high-pier continuous rigid frame bridge according to claim 6, characterized in that: In the step seven, after the concrete strength reaches 90% of the design strength and the concrete age is not less than 7 days, prestressed construction is carried out, and the prestressed steel strand adopts a one-time tensioning process. After the longitudinal and transverse tensioning are completed, the steel strand is cut with a grinding wheel machine, and the length of the exposed steel strand outside the anchor ring is controlled to 3-5 cm, and then the anchor is sealed.

8. The method for constructing a high-pier continuous rigid frame bridge according to claim 7, characterized in that: In step eight, the steps of moving the hanging basket include: removing the inner formwork system and the side formwork system; removing the bottom film system; removing the pads, laying them to the front box girder, and moving the guide slide to the front box girder; anchoring the slide; moving the main girder system of the hanging basket forward, and driving the side formwork system, the inner formwork system, and the bottom formwork system forward together; the hanging basket is in place, anchoring the main girder; and lifting the bottom formwork system. Improve the side formwork system; Improve the internal mold system; Prepare for the next section construction.

9. The method for constructing a high-pier continuous rigid frame bridge according to claim 8, characterized in that: In the step nine, during the stage construction, the setting out and erecting formwork is carried out when the temperature is stable.

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