CN102373768A

CN102373768A - Concrete beam with reticular steel bars arranged at beam end

Info

Publication number: CN102373768A
Application number: CN201110342934XA
Authority: CN
Inventors: 黄靓; 曾敏; 许恺钧
Original assignee: Hunan University
Current assignee: Hunan University
Priority date: 2011-11-03
Filing date: 2011-11-03
Publication date: 2012-03-14

Abstract

The invention discloses a concrete beam with reticular steel bars arranged at a beam end. Under the effect of a symmetrical concentration load, main stress trace lines of a single support frame with a rectangular cross section are in a reticular shape at a near support seat shearing bending section (1), and the beam is easy to generate inclined cross section damage in the region. Reticular steel bars are distributed in region, the constraint force can be enhanced, the carrying capability of the inclined cross section of the beam is improved, the advanced crushing of the concrete in the shearing and pressing region is effectively prevented, the ductility of the beam is greatly improved, and the shock resistant performance of a component is improved. The reticular steel bars consist of vertical dense vertical ribs (3), vertical ribs (5) and dense hoop ribs (2), the configuration is simple, and the construction is convenient. Because weak parts of the beam are enhanced, the stress performance of the beam is greatly improved, the building material consumption can be relatively reduced under the condition of the same stress, and the cost is saved.

Description

A kind of beam-ends is arranged the concrete beam of steel mesh reinforcement

Technical field

The present invention relates to a kind of beam-ends and arrange the concrete beam of steel mesh reinforcement.

Background technology

Traditional reinforced concrete beam mainly leans on longitudinal reinforcement (5) to bear pulling force, and concrete bears pressure, but after diagonal crack appears in beam-ends; The tensile region reinforcing bar further stretches; Cut the nip concrete area and constantly reduce, the back is under the acting in conjunction of shearing stress and compressive stress, and it is crushed to cut the nip concrete.Because concrete crushing is a brittle fracture, greatly reduce the ductile performance of beam.If strengthen arrangement of reinforcement in beam end, strengthen the beam-ends weak part, just can avoid cutting the nip concrete and crush in advance, so not only can improve the stress performance of beam, and can realize very high ductility.

In recent years owing to from all parts of the world frequent earthquake takes place, so in the engineering to member ductility require increasingly high; Yet concrete fragility pressurized; Influenced the anti-seismic performance of beam greatly, and the beam that the end arrangement of reinforcement strengthens can solve this difficult problem well, thereby improve the anti-seismic performance of structure.

Summary of the invention

The invention provides a kind of novel, concrete beam that beam-ends with good stress performance is arranged steel mesh reinforcement.Like Fig. 1, under the load action, the principal stress trajectory of square-section simply supported beam is cut curved section (1) for netted near bearing in symmetric set, and under the guaranteed situation of span centre normal section anti-bending bearing capacity, beam is prone to take place the sloping section in this zone to be destroyed.As arranging the steel mesh reinforcement consistent with the principal stress trajectory direction at beam-ends, increase restraint forces, can improve the stress performance of beam well.But, be configured to like Fig. 2,3, the steel mesh reinforcement shown in 4 for easy construction.Its steel mesh reinforcement is made up of the vertical muscle (3) of vertical encryption, vertical muscle (5) and encryption stirrup (2); The vertical muscle (3) of vertical encryption is arranged along the beam section both sides; The vertical vertical spacing of encrypting the vertical spacing of vertical muscle (3) less than his the vertical muscle (5) in position of Liangqi; Encrypt the spacing of the spacing of stirrup (2), thereby strengthen restraint forces, improve the supporting capacity that beam end is cut curved section (1) less than its position stirrup (4) of Liangqi.

The present invention arranges steel mesh reinforcement in beam end, effectively prevents to cut the nip concrete and crushes in advance, improves the ductility of beam greatly, improves the shock resistance of member.It is simple and easy to cut curved section (1) arrangement of reinforcement, just like same section short beam, so easy construction.Owing to strengthened the weak part of beam, improved the stress performance of beam, under force-bearing situation of the same race, can reduce building materials consumption relatively, practice thrift cost.

Description of drawings

Fig. 1 is the principal stress trajectory of square-section simply supported beam under the load action in the symmetric set;

Fig. 2 is the concrete beam normal cross-section sketch map that beam-ends of the present invention is arranged steel mesh reinforcement;

Fig. 3 is the A-A generalized section of beam of the present invention;

Fig. 4 is the B-B sectional schematic diagram of beam of the present invention.

Marginal data:

1 steel mesh reinforcement layout area; 2 encrypt stirrup;

3 encrypt vertical muscle; The stirrup of 4 beams;

The vertical muscle of 5 beams.

The specific embodiment

Below will combine accompanying drawing that the present invention is done further explanation:

At first set up the stirrup 4 and the vertical muscle 5 of beam, cut at beam-ends on this basis then that 1 of curved section is upright encrypts stirrup 2 and encrypt vertical muscle 3, last fluid concrete has just constituted the concrete beam that this kind beam-ends is arranged steel mesh reinforcement.

Claims

1. a beam-ends is arranged the concrete beam of steel mesh reinforcement; It is characterized in that: near the simply supported beam bearing of square-section, cut curved section (1) and arrange steel mesh reinforcement; Its steel mesh reinforcement is made up of the vertical muscle (3) of vertical encryption, vertical muscle (5) and encryption stirrup (2); Vertical encryption is indulged muscle (3) and is arranged along the beam section both sides, vertically encrypts the vertical spacing of indulging muscle (3) is indulged muscle (5) less than his position of Liangqi vertical spacing.

2. beam-ends according to claim 1 is arranged the concrete beam of steel mesh reinforcement, it is characterized in that: encrypt the spacing of the spacing of stirrup (2) less than its position stirrup (4) of Liangqi.