CN103321137B - Groove-shaped bridge beam - Google Patents

Abstract

The invention discloses a trough-shaped bridge, which comprises left and right longitudinal girders, bottom plates and left and right web plates, and is characterized in that the left and right longitudinal girders extend in the span direction to form a longitudinal force-bearing structural system, and the bottom plate is transversely arched. The left and right sides are respectively connected to the lower sides of the left and right longitudinal beams, the left and right webs are placed at an angle inclined outward to the horizontal, and the lower sides of the webs are respectively connected to the upper sides of the left and right longitudinal beams. The present invention adopts the transverse arched bottom plate to replace the plate-shaped bottom plate of the conventional trough bridge. Compared with the conventional trough bridge, the present invention can reduce the thickness of the bottom plate of the trough bridge, save the amount of concrete and steel reinforcement materials, and can Increase the spanning capacity of the trough bridge.

Description

a trough bridge

technical field

The invention belongs to the technical field of civil engineering and relates to a bridge engineering structure, in particular to a trough bridge.

Background technique

The existing trough bridge consists of longitudinal girders, bottom plates and webs on both sides to form the main structure of the trough bridge. The bottom plate adopts a flat plate structure. Only a larger thickness can meet the requirements, generally 40cm thick. A thicker bottom plate leads to an increase in the amount of structural engineering and investment, and makes the center of gravity of the trough bridge lower, and the cross-sectional efficiency index is on the low side. Unfavorable, it weakens the spanning capacity of the trough bridge.

Contents of the invention

The purpose of the present invention is to overcome the defects of the prior art and provide a trough bridge with a thinner bottom plate and greater spanning capacity.

In order to achieve the above object, technical scheme of the present invention is:

A trough-shaped bridge, comprising left and right longitudinal girders, base plates and left and right web plates, characterized in that: the left and right longitudinal girders extend in the span direction to form a longitudinal force-bearing structural system, the base plate is transversely arched, and its left and right sides The sides are respectively connected to the lower sides of the left and right longitudinal beams, and the left and right webs are arranged at an angle inclined outward to the horizontal, and the lower sides of the webs are respectively connected to the upper sides of the left and right longitudinal beams.

The above-mentioned transverse arch axis of the bottom plate is any one of circular arc shape, parabolic shape or catenary shape.

The transverse arched cross section of the bottom plate mentioned above is a plate arch or a box arch.

The transverse arch rise-span ratio of the above-mentioned bottom plate is 1/4 to 1/16.

The left and right webs described above are outwardly and horizontally inclined at an angle greater than or equal to 45 degrees and less than 90 degrees.

The upper surface of the base plate mentioned above is also provided with a bridge deck pavement layer.

A trough-shaped bridge of the present invention has the following advantages and beneficial effects after adopting a transverse arched bottom plate:

(1) The force on the bottom plate is optimized. After adopting the transverse arched bottom plate, the force on the bottom plate is mainly bearing pressure, and the bending moment on the bottom plate is reduced;

(2) Since the bending moment on the bottom plate is reduced, the amount of bending steel bars on the bottom plate can be reduced and the thickness of the bottom plate can be reduced;

(3) The thickness of the base plate is reduced, which can significantly reduce the amount of concrete materials. Compared with conventional channel bridges, the amount of concrete materials can be saved by 10% to 15%, which significantly reduces the weight of the base plate structure and reduces the construction cost;

(4) After the self-weight of the bottom slab is reduced, the longitudinal bending moment caused by the self-weight of the bottom slab is also reduced, which can reduce the amount of longitudinal prestressed tendons; at the same time, the reduction of the self-weight of the bottom slab can increase the spanning capacity of the trough bridge.

(5) The bottom plate adopts a transverse arched bottom plate, which moves the center of gravity of the trough bridge structure upwards, improves the efficiency index of the section where the longitudinal prestressed tendons are located, further reduces the amount of longitudinal prestressed tendons, and further reduces the project cost.

The application advantage of the trough bridge is that it can not only effectively reduce the building height of the bridge superstructure, but also has the advantages of reducing noise, anti-traffic interference, anti-lateral wind, and ensuring driving safety. It is especially suitable for crossing traffic lines in densely populated urban areas And traffic lines crossing areas with large crosswinds. The trough-shaped bridge of the present invention not only solves a series of problems caused by the over-thickness of the bottom plate of the traditional trough-shaped bridge, but also improves the mechanical performance of the bottom plate of the trough-shaped bridge, reduces the engineering cost, and increases the span of this type of bridge ability.

Description of drawings

Fig. 1 is a schematic top view of the structure of the trough bridge of the present invention.

FIG. 2 is a cross-sectional view along line A-A of FIG. 1 .

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

As shown in Figures 1 and 2, a trough-shaped bridge is composed of left and right longitudinal girders 1, transverse arched bottom plates 2 and left and right webs 3 to form the main structure of a trough-shaped girder bridge, and the left and right longitudinal girders 1 are aligned in the span direction. Extend to form a longitudinally stressed structural system. The transverse arched axis line used by the transverse arched base plate 2 is arc-shaped, the vault of the transverse arched base plate 2 is located at the center line of the cross section of the bridge, and the two sides of the transverse arched base plate 2 are integrally connected with the left and right longitudinal beams 1 , the left and right webs 3 are arranged outwardly at an angle inclined to the horizontal plane, and the lower sides of the left and right webs are respectively connected to the upper sides of the left and right longitudinal beams.

Concrete construction process of the present invention is as follows:

(1) First set up the bracket and formwork;

(2) Binding steel bars, including steel bars for bottom longitudinal beams, bottom plates and web parts;

(3) Reserving the channel for the prestressed reinforcement of the longitudinal beam, pouring concrete, including the longitudinal beam, bottom plate and web;

(4) Stretch the prestressed steel tendon, anchor the end, pour the anchor head concrete and carry out construction and maintenance.

Corresponding structural features of the present invention:

(1) The floor adopts a transverse arched structure, and the rise-span ratio of the transverse arched floor varies from 1/16 to 1/4;

(2) Both sides of the transverse arched bottom plate are integrally connected with the bottom longitudinal beam;

(3) The bottom longitudinal beam mainly bears the longitudinal bending moment;

(4) The transverse arched bottom plate is mainly pressure-bearing, and the bending moment is small, so the bottom plate can be made thinner than the flat bottom plate, which reduces the amount of bending steel bars and concrete materials on the bottom plate, which is different from that of conventional channel bridges. In comparison, the amount of concrete materials can be saved by 10% to 15%, which significantly reduces the self-weight of the bottom plate, and the longitudinal bending moment caused by the self-weight of the bottom plate is also reduced, increasing the spanning capacity of the trough bridge.

(5) The bottom plate adopts a transverse arch structure, which can move the center of gravity of the trough bridge structure upwards, improve the efficiency index of the section where the longitudinal prestressed tendons are located, further reduce the amount of longitudinal prestressed tendons, and further reduce the project cost.

Claims (1)

1. a channel change bridge, comprise left-right longeron (1), base plate (2) and left and right web (3), it is characterized in that: described left-right longeron (1) extends to form longitudinal stress structural system to across direction, footpath, described base plate (2) is in horizontal arch, the axial alignment of described horizontal arch is circular arc, parabola shaped or stretched wire is linear, the section form of horizontal arch is plate arch or box-shaped arch, the ratio of rise to span of horizontal arch is 1/4 to 1/16, and its limit, left and right sides is connected below with described left-right longeron (1) respectively; Described left and right web (3) is outwards more than or equal to 45 degree with horizontal plane one, and the angle being less than 90 degree is settled, and the following of left and right web (3) is connected with described left-right longeron (1) top respectively.