RU165808U1 - SPAN STRUCTURE OF A CURTAIN BRIDGE - Google Patents

Abstract

The utility model relates to the field of building structures, in particular to the structures of superstructures of continuous reinforced concrete road bridges. This design can also be used as floors in industrial and civil engineering.

The utility model is aimed at increasing the strength and crack resistance of support sections for the formation of inclined cracks to the longitudinal axis of structures of reinforced concrete spans of continuous bridges made of monolithic reinforced concrete ..

The span of a continuous bridge made of precast-monolithic reinforced concrete in a longitudinal section can be made of variable or constant stiffness. In the longitudinal section, the span is made of a continuous section in the form of a monolithic plate of constant or variable section height. The span is reinforced with prefabricated pre-stressed reinforced concrete bars of factory manufacture or made on special stands at the construction site. Reinforced concrete blocks are located along sections along the length of the spans in the lower span zones and in the upper and lower zones above the supports. On the front side, precast-monolithic reinforced concrete bars are equipped with end outlets of prestressed reinforcement and spatial frames that have an anchor at the ends of outlets of prestressed reinforcement. To ensure compatibility of the deformation of reinforced concrete bars and monolithic concrete, the slabs along the length are made of a complex cross section with dowels and with transverse U-shaped outlets made of reinforcement of the spatial frame of the bar.

The span of the continuous bridge has increased strength and crack resistance of inclined sections, which contributes to their use for covering large spans.

As a prototype of the constructive solution, according to the utility model patent “Continuous bridge span”, continuous precast monolithic reinforced concrete spans with a slab of carriageway made of monolithic concrete, in the stretched zones of which are prestressed reinforced concrete bars made in the factory or on the construction site, are considered at special stands [4].

Patent Search Literature

1. Polivanov N.I. Design and calculation of reinforced concrete and metal bridges., Transport Publishing House, Moscow, 1970 - 516 p.

2. Murashev V.I., Sigalov E.E., Baykov V.N. Reinforced concrete structures., General course. / Edited by prof. Pasternak P.L., State Publishing House of Literature on Construction, Architecture and Building Materials. - M., 1962 .-- 660 s.

3. Ivanov G.P., Kuklin A.N., Taracheva E.A. The span of the continuous bridge. Utility Model Patent: RU: No. 151169, IPC E01D 12/00; 101/28. Application: No. 2013152241/03 of 11/25/2013 Bull. No 9 on 03/27/13.

Description

The utility model relates to the field of building structures, in particular to the structures of superstructures of continuous reinforced concrete road bridges. This design can also be used as large-span. continuous floors of reinforced concrete in industrial and civil engineering.

The known construction of the span of continuous reinforced concrete bridge of constant or variable stiffness, both in length and in width of the bridge of monolithic unstressed reinforced concrete reinforced by longitudinal working span and supporting reinforcement, transverse and inclined rods in the span and on supporting sections ([1], Polivanov NI Design and calculation of reinforced concrete and metal bridges., Publishing house "Transport", Moscow, 1970, p. 159, Fig. 66).

The disadvantages of such constructions of superstructures are their high cost and material consumption, significant complexity and duration of construction.

A known span structure of a continuous bridge of constant and variable stiffness along its length and width from monolithic prestressed reinforced concrete reinforced by transverse non-stressed reinforcement and longitudinal tensile reinforcement with tension reinforcement on concrete at a construction site when the prestressed reinforcement is placed in ducts laid in the form of a sinusoid to its tension in the stretched zones, both in the middle part of the spans and in support sections by bending the tensile reinforcement at porn sites ([2], Murashev VI, Sigalov E.E., Baykov VN Reinforced concrete structures., General course ./ Edited by Doctor of Technical Sciences, Professor Pasternak P.L., State Publishing House literature on construction, architecture and building materials. - M., p. 247, fig. HP. 18, d).

The disadvantages of the design of a monolithic span of a continuous bridge of constant and variable stiffness along its length and width are: the high cost and complexity of the work on the construction of the span, as well as the increased construction time.

As a prototype of the constructive solution, the construction of the continuous bridge span structure from precast-monolithic prestressed reinforced concrete reinforced with working longitudinal tensile reinforcement of the lower and upper grids, frames and prestressed reinforced concrete bars of high-strength non-shrinkable cast concrete located in the stretched zones in the middle part is considered spans in the lower zone of the section of the plate and on the supporting sections in the upper zone of the plate of the span (see [3], Patent for utility model RU No. 151169 U1, IPC E01D 12/00).

The disadvantage of this design of the span of the continuous bridge is the low strength and crack resistance by the formation of inclined cracks in the supporting sections of the slab of a monolithic span, made without transverse reinforcement.

The utility model is aimed at increasing the strength and crack resistance of support sections for the formation of inclined cracks and the rigidity of the spans of continuous bridges made of monolithic reinforced concrete.

The result is achieved by the fact that the span of the continuous bridge from precast-monolithic prestressed reinforced concrete reinforced with working longitudinal tensile reinforcement of the lower and upper grids, frames and prestressed reinforced concrete bars of high-strength non-shrinkable cast concrete located in stretched zones in the middle of the spans in the lower zone of the cross-section of the plate and in the supporting sections in the upper zone of the plate, the span in the lower zones of the supporting sections is reinforced pre-n conjugate concrete bars arranged at sites in the clearance between the upper reinforcement bars of reinforced concrete slabs stretched zones span.

The span of a continuous bridge made of precast-monolithic prestressed concrete is carried out at a construction site with the involvement of the industrial construction base of ZhBK plants for the manufacture of prestressed reinforced concrete bars and monolithic cast self-compacting concrete.

For the manufacture of reinforced concrete bars, high-strength non-shrink cast concrete based on ready-made dry mixes is used, which does not require compaction, which within 2-3 days allows to obtain concrete strength of at least 50 MPa.

The use of prestressed reinforced concrete bars made of high-strength non-shrinkable cast concrete of a class with a compressive strength of at least B50 as reinforcement increases the strength, crack resistance and stiffness of the span of continuous bridges and ceilings made of monolithic concrete.

A utility model is illustrated in the drawings: FIG. 1 and FIG. 2 - spans of continuous bridges from precast-monolithic prestressed reinforced concrete reinforced with prestressed reinforced concrete beams; FIG. 3 - section I-I in the span; FIG. 4 - section II-II on the supporting sections of the plate.

The span of a continuous bridge made of precast-monolithic reinforced concrete is made in the longitudinal section of constant (Fig. 1) or variable (Fig. 2) stiffness.

The span of a continuous bridge made of precast-monolithic prestressed reinforced concrete along the entire length of the spans in the lower and upper zones is reinforced with working longitudinal non-tensile reinforcement grids of rod reinforcement 1 and longitudinal working reinforcement of prestressed reinforced concrete bars: in the middle of the spans in the lower zone plate 2 and in supporting sections: in the upper stretched zone of the plate 3 and in the lower compressed zone of the plate 4.

The span of the continuous bridge is reinforced with prefabricated prestressed concrete bars of three sizes in length. The length of the span reinforced concrete bars 2 and supporting bars located in the upper stretched zone of the plate 3 is taken to be the minimum length, according to the diagram of bending moments, taking into account the inclusion of tensile reinforcing meshes 1 and outlets of tensile reinforcement 5 from reinforced concrete bars 2 and 3. The length of reinforced concrete bars bars located in the lower zones of the supporting sections is determined by the thickness of the monolithic plate h on the support and the estimated length of the projection of the inclined crack on the longitudinal axis of the reinforcement taken at least 2h. On the end side, reinforced concrete bars 1 are equipped with end releases of prestressing reinforcement 5, which are made with anchors. The joint work of reinforced concrete bars 2, 3 and 4 with cast concrete slabs of the span structure 8 is ensured by the keys 9 made on the side faces of the bars and flexible reinforcing joints 10 made in the form of U-shaped outlets from reinforced concrete bars 2, 3, 4.

Reinforced concrete bars 2 and 4 of reinforcing the lower zone of the plate are installed on the transverse reinforcement 6 between the working longitudinal rods 1 of the lower mesh with a mesh of not more than 200 × 200 mm and fixed in the design position using a knitting wire. Reinforced concrete bars 3 reinforcing the upper zone of the supporting sections of the slab are installed in the design position between the longitudinal rods 1 of the upper mesh using U-shaped clamps 12 of the reinforcement bars installed on the bars 2, 4 reinforcing the lower zone of the slab with a step of 1 m in adjacent cells with respect to longitudinal reinforcement 1 bottom mesh. The transverse reinforcement 7 of the upper mesh is installed on the longitudinal reinforcement 1 of the upper mesh and reinforced concrete bars 3. For concreting the span plate 8, self-compacting high-strength concrete is used, which does not require the use of compaction with deep vibrators. The transverse reinforcement 6 of the bottom mesh of the reinforcing plate is installed on plastic clips 11, which are installed in increments of 1 m in a checkerboard pattern.

The span of the continuous bridge has several advantages, in comparison with the prototype:

1. Increased strength and crack resistance of the support sections of the monolithic plate by the formation of inclined cracks.

2. An increase in the bending stiffness of the bridge span plate in the supporting sections due to the creation of a hidden cantilever-beam calculation scheme in the span plate.

Claims (1)

The span of a continuous bridge made of precast-monolithic prestressed reinforced concrete reinforced with working longitudinal tensile reinforcement of the lower and upper grids, frames and prestressed reinforced concrete bars of high-strength non-shrinkable cast concrete located in stretched zones in the middle of the spans in the lower section of the slab and on supporting sections in the upper zone of the span plate, characterized in that the span of the bridge in the lower zones of the supporting sections of the reinforcement plate It is pre-stressed with reinforced concrete bars located in the light areas between the reinforced concrete bars of the reinforcement of the upper elongated zone of the span plate.

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