Pier column slimmed steel truss landscape bridge

Abstract

The utility model provides a pier stud slim steel truss landscape bridge, including steel truss, slim pier stud, pier stud foundation, bridge abutment and end support, the steel truss is the superstructure of bridge, the slim pier stud is the steel structural member and bears pulling force, the upper end of pier stud foundation is connected with slim pier stud, and the end support is connected with the bridge abutment. The bridge abutment comprises an abutment body and a foundation of the abutment body, and the end supports are connecting supports between the two ends of the steel truss and the bridge abutment body. Before the slim pier column is installed, a temporary ballasting load larger than the second-stage dead load and the use live load of the bridge is applied to the steel truss behind the falling frame, and after the slim pier column is installed, the temporary ballasting load is removed. The pier column bears tension all the time in the use process of a bridge, the problem that the pier column is pressed to be unstable does not exist, a high-strength steel structure component can be adopted, the pier column is thinned, the landscape effect of the bridge is improved, the utilization rate of steel strength of the steel truss can be remarkably improved, and waste of materials is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of bridge construction engineering, and particularly relates to a steel truss landscape bridge with slenderized piers. Background Art

[0002] With the continuous development of social economy and the continuous improvement of the public aesthetic level, people's demand for bridge structures is no longer limited to meeting traffic functions, and the pursuit of the landscape of bridge architecture is also getting higher and higher.

[0003] Due to the advantages of light structure, fast construction, and modern shape, the steel truss bridge has become the preferred bridge type for urban landscape bridges. As the main load-bearing member, the steel truss is required to have sufficient strength and stiffness during bridge construction design. Due to the characteristics of light weight and high strength of steel structures, the stiffness usually plays a controlling role in the design of steel trusses, while their strength often has a large surplus, and the strength of steel is not fully utilized, resulting in waste of materials. In addition, when the bridge length is relatively long, it is generally necessary to add piers to support the beam body to reduce the span and meet the stiffness requirements of the beam body. However, the piers of existing steel truss bridges are designed as compression members. Due to the need to meet both strength and stability requirements, their cross-sectional dimensions are often relatively thick, as shown in Figure 1 and Figure 2 shown, which affects the landscape effect of the steel truss bridge. Content of the Utility Model

[0004] In order to solve the above technical problems, the utility model provides a steel truss landscape bridge with slenderized piers to solve the problems raised in the above background art.

[0005] To achieve the above object, the technical solution adopted by the utility model is:

[0006] A steel truss landscape bridge with slenderized piers includes a steel truss, slenderized piers, pier foundations, abutments, and end bearings. The steel truss is the upper structure of the bridge. The slenderized piers are steel structure members that bear tension and are arranged between two abutments. The upper ends are connected to the bottom of the joints of the steel truss web members and the lower chord members. The upper ends of the pier foundations are connected to the slenderized piers. The abutments include the abutment bodies and their foundations. The end bearings are the connecting bearings between the two ends of the steel truss and the abutments. The two ends of the steel truss are connected to the upper ends of the abutment bodies through the end bearings.

[0007] Furthermore, the slenderized piers adopt column piers or V-shaped piers, and one or at least two are arranged in the transverse direction of the bridge.

[0008] Furthermore, the slenderized piers are rigidly connected or hinged to the steel truss and the pier foundations.

[0009] Furthermore, one or at least two slenderized piers are arranged in the longitudinal direction of the bridge.

[0010] The construction method of the steel truss landscape bridge with slenderized pier columns described in the present utility model is as follows:

[0011] Construction stage 1: Construct the pier column foundation and abutment, and install the end support on the top surface of the abutment body.

[0012] Construction stage 2: The factory processes and manufactures the steel truss in segments according to the linear shape considering the camber, transports it to the site and erects it on the temporary piers, and then completes the connection between the steel truss segments and the connection between the steel truss and the end support.

[0013] Construction stage 3: Remove the temporary support, and then apply a temporary heavy load on the steel truss that is greater than the secondary permanent load and live load of the bridge, causing the steel truss to produce downward vertical elastic deformation.

[0014] Construction stage 4: Install the slenderized pier column and complete the connection between the slenderized pier column, the steel truss and the pier column foundation.

[0015] Construction stage 5: Remove the temporary heavy load applied on the steel truss. At this time, the slenderized pier column generates a tensile force due to restricting the upward recovery of the elastic deformation of the steel truss, and this tensile force is greater than the pressure generated by the slenderized pier column under the action of the secondary permanent load and live load of the bridge; then carry out the construction of the bridge auxiliary facilities to complete the construction of the bridge.

[0016] The present utility model has the following beneficial effects compared with the prior art:

[0017] 1. In the steel truss landscape bridge constructed by the present utility model, the pier column bears tensile force and there is no problem of buckling under compression. High-strength steel structure members can be used, realizing the slenderization of the pier column and improving the bridge landscape effect.

[0018] 2. Under the live load, the slenderized pier column of the landscape bridge of the present utility model can be used as the support of the steel truss like the traditional compression pier column, reducing the span of the steel truss and making the stiffness of the steel truss meet the specification requirements.

[0019] 3. Before installing the slenderized pier column of the landscape bridge of the present utility model, by applying a temporary heavy load greater than the secondary permanent load and live load of the bridge on the steel truss after derricking, the utilization rate of the steel strength of the steel truss can be significantly improved, reducing material waste. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the structural system of the steel truss bridge in the prior art;

[0021] Figure 2 It is a schematic cross-sectional view of the pier column of the steel truss bridge in the prior art;

[0022] Figure 3 Schematic diagram of the structural system of the steel truss landscape bridge of the present utility model;

[0023] Figure 4 Schematic diagram of the cross-section at the column pier of the steel truss landscape bridge of the present utility model;

[0024] Figure 5 Schematic diagram of the cross-section at the column pier of the V-shaped pier of the steel truss landscape bridge of the present utility model;

[0025] Figure 6 Schematic diagram of the construction process of the steel truss landscape bridge of the present utility model.

[0026] In the figure, the markings are: 1. Steel truss; 2. Slimmed-down pier column; 3. Pier column foundation; 4. Abutment; 5. End support. Specific implementation manner

[0027] The following further describes the present utility model in detail in conjunction with the accompanying drawings and specific implementation manners:

[0028] A steel truss landscape bridge with a slimmed-down pier column provided by the present utility model can achieve the slimming of the pier column, improve the bridge landscape effect, and can significantly improve the utilization rate of the steel strength of the steel truss, reducing material waste.

[0029] The structural system of the steel truss landscape bridge of the present utility model is as Figure 3 shown, including a steel truss 1, a slimmed-down pier column 2, a pier column foundation 3, an abutment 4, and an end support 5. The steel truss 1 is the upper structure of the bridge. The slimmed-down pier column 2 is a steel structure member and bears tension. It is arranged between two abutments, and its upper end is connected to the bottom of the joint of the web member and the lower chord member of the steel truss. The upper end of the pier column foundation 3 is connected to the slimmed-down pier column. The abutment 4 includes a pier body and its foundation. The end support 5 is a connecting support between the two ends of the steel truss and the abutment. The two ends of the steel truss 1 are connected to the upper end of the pier body of the abutment 4 through the end support 5.

[0030] Furthermore, the slimmed-down pier column 2 adopts a column pier or a V-shaped pier, and one or at least two are arranged in the transverse direction of the bridge.

[0031] Furthermore, the slimmed-down pier column 2 is rigidly connected or hinged to the steel truss 1 and the pier column foundation 3.

[0032] Furthermore, one or at least two slimmed-down pier columns 2 are arranged in the longitudinal direction of the bridge.

[0033] A construction method of a steel truss landscape bridge with a slimmed-down pier column of the present utility model is characterized in that the specific steps are as follows:

[0034] Construction stage 1: Construct the pier column foundation 3 and the abutment 4, and install the end support 5 on the top surface of the pier body of the abutment 4;

[0035] Construction stage 2: The factory fabricates and manufactures the steel truss 1 in segments according to the alignment considering the camber, transports it to the site and erects it on the temporary piers, and then completes the connection between the segments of the steel truss 1 and the connection between the steel truss 1 and the end support 5.

[0036] Construction stage 3: Remove the temporary supports, and then apply a temporary dead load greater than the secondary permanent load and live load of the bridge on the steel truss 1, causing the steel truss 1 to produce a downward vertical elastic deformation.

[0037] Construction stage 4: Install the slenderized pier column 2 and complete the connection between the slenderized pier column 2, the steel truss 1 and the pier foundation 3.

[0038] Construction stage 5: Remove the temporary dead load applied on the steel truss 1. At this time, due to restricting the upward recovery of the elastic deformation of the steel truss 1, the slenderized pier column 2 generates a tensile force, which is greater than the pressure generated by the slenderized pier column 2 under the action of the secondary permanent load and live load of the bridge; then the construction of the bridge ancillary facilities is carried out to complete the construction of the bridge.

[0039] The following further details the present utility model with an actual project as an example.

[0040] This embodiment is a two-span steel truss pedestrian bridge with a span layout of (35 + 35) m, the total width of the steel truss is 4.8 m, the piers adopt double-column piers with a height of 5 m, the steel truss adopts a triangular truss form with a truss height of 3.5 m, a joint spacing of 7 m, and a truss spacing of 4.5 m. The steel truss uses Q355C steel, the upper and lower chord members both adopt box sections of 500×300×20 mm, and the web members adopt box sections of 250×250×16 mm.

[0041] According to Figure 1 and Figure 2 When designing using the existing technology, the calculation results show that the first vertical natural vibration frequency of the steel truss is 6.12 Hz, meeting the design specification requirement of not less than 3 Hz (if no intermediate pier columns are set, the first vertical natural vibration frequency of the steel truss is 1.73 Hz, not meeting the design specification requirement of not less than 3 Hz); the maximum stress of the steel truss is 68.5 Mpa, and the material strength utilization rate is only 24.9%; the maximum vertical reaction force of a single pier column in the transverse direction of the bridge is 1142 kN, and the pier column bears a large vertical pressure. The pier column adopts a concrete circular-section pier column, and its diameter is approximately 600 mm to meet the stress requirements. At this time, the slenderness ratio of the pier column is 8.33.

[0042] According to Figure 3 、 Figure 4 and Figure 6The technology of the present utility model is adopted for design. The pier column uses two solid steel bars with a diameter of 60 mm. The calculation results show that the first vertical natural vibration frequency of the steel truss is 6.04 Hz, which changes very little compared with the design results of the prior art and meets the requirement of not less than 3 Hz in the design specification; the maximum stress during the construction process of the steel truss is 199.3 MPa, the maximum stress in the completed bridge state is 194.3 MPa, and the maximum stress in the service state is 225.4 MPa. The utilization rate of material strength is increased to about 83.5%; the maximum tension during the construction process of a single pier column is 795 kN, and the stress is 281.0 MPa. The use of 40Cr high-strength alloy steel meets the requirements; the tension of a single pier column in the cross-bridge direction in the completed bridge state is 621 kN, and the minimum tension in the service state is 226 kN. The maximum tension in the service state is less than the maximum tension during the construction process. The pier column has been bearing tension during the use of the bridge and there is no instability problem. At this time, the slenderness ratio of the pier column is 83.3, which is 10 times that of the pier column in the prior art, realizing the refinement of the pier column.

[0043] The above is only the preferred embodiment of the present utility model, and it is not a limitation to the present utility model in any other form. Any modification or equivalent change made according to the technical essence of the present utility model still belongs to the scope protected by the present utility model.

Claims

1. A steel truss landscape bridge with slenderized piers, comprising a steel truss (1), slenderized piers (2), pier foundations (3), abutments (4) and end supports (5), characterized in that: The steel truss (1) is the upper structure of the bridge. The slenderized pier (2) is a steel structural member that bears tension and is arranged between two abutments (4). The upper end of the slenderized pier (2) is connected to the bottom of the node between the web and the lower chord of the steel truss (1). The upper end of the pier foundation (3) is connected to the slenderized pier (2). The abutment (4) includes an abutment body and a foundation thereof. The end support (5) is a connecting support between the two ends of the steel truss (1) and the abutment (4). The two ends of the steel truss (1) are connected to the upper end of the abutment body of the abutment (4) through the end support (5).

2. The steel truss landscape bridge with slim piers according to claim 1, characterized in that: The slenderized piers (2) are columnar piers or V-shaped piers, and one or at least two are arranged in the transverse direction of the bridge.

3. A steel truss landscape bridge with slim piers according to any one of claims 1 and 2, characterized in that: The slenderized pier column (2) is rigidly connected or hingedly connected to the steel truss (1) and the pier column foundation (3).

4. A steel truss landscape bridge with slim piers according to any one of claims 1 and 2, characterized in that: One or at least two of the slenderized piers (2) are arranged along the bridge direction.

Images