CN102953347A - Design internal stress analyzing method for hinged hollow plank girder bridge with reinforced transverse prestress - Google Patents

Abstract

The invention discloses a design internal stress analyzing method for a hinged hollow plank girder bridge with reinforced transverse prestress. Transverse prestress is applied to reinforce a hollow plank girder bridge with a hinged joint, and the reinforcing mode is one of effective measures for solving the single-plate force applying and the crack along the hinged joint of the hinged hollow plank girder bridge. The patent aims at the characteristics that the plank girder reinforced by the reinforcing method can bear bending bidirectional stress in the longitudinal and transverse directions, and simulates the reinforced hollow plank girder bridge to an orthotropic anisotropic plate and adopts a corresponding longitudinal-transverse rigidity hypothesis to propose an internal stress analyzing method for designing the bridges with the reinforced transverse prestress, so that the problem that no practical design calculation methods are available for the internal stress analysis of the hinged hollow plank girder bridge is solved, and meanwhile, the complexity and time consumption of the modeling calculation in the finite element software calculation are avoided.

Description

The design flexibility method of the hinged Hollow Slab Beam Bridge that transverse prestress is reinforced

Technical field

The present invention relates to a kind of design flexibility method of hinged Hollow Slab Beam Bridge of transverse prestress reinforcing, belong to technical field of bridge engineering.

Background technology

Traditional Hollow Slab Beam Bridge design mainly is to rely on hinge seam concrete transmission limited between plate-girder and common stressed, but along with the progress of science and technology and the continuous increase of vehicular load, this construction design method exposes serious defective, i.e. continuing to increase along with vehicular load, the transverse bending of bridge increases, and the horizontal anti-bending strength of this bridge-type structure a little less than, causing original hinge seam concrete to be easy to cracking, fracture or curved scissors destroys, the vehicular load that can not effectively distribute causes structural veneer stressed and cave in.

And this type of bridge is applied bridge direction across bridge prestress system (some roads transverse prestress steel strand generally are set) between span centre or 1/4 is striden, can increase the direction across bridge of bridge bending rigidity, reduce the inhomogeneous of load cross direction profiles, prevent the stressed and bridge floor cracking of the veneer of bridge, improve the durability of structure.

But how the bridge after this type of reinforcing is carried out design analysis calculate, also do not have the method for practical simplicity at present.In the past to the articulated slab beam bridge, generally utilize transversely hinge to calculate its load cross direction profiles more, space problem is reduced to plane problem, but for the hinged blank board bridge behind the transversely strengthening, traditional transversely hinge supposition is false, it does not meet the supposition that rigidly connects beam and elastic bearing beam method yet, the cross direction profiles that adopts existing finite element software Modeling Calculation to reinforce axle casing affects line and bridge internal force, on the one hand need to be to skilled operation and the Rational Model of finite element software, on the other hand, its Modeling Calculation is also had complexity and a property consuming time.

Therefore, for solving the problems of the technologies described above, the design flexibility method of the hinged Hollow Slab Beam Bridge that the necessary transverse prestress that a kind of improvement is provided is reinforced is to overcome described defective of the prior art.

Summary of the invention

For addressing the above problem, the object of the present invention is to provide a kind of design flexibility method of hinged Hollow Slab Beam Bridge of transverse prestress reinforcing.

For achieving the above object, the technical scheme taked of the present invention is: the design flexibility method of the hinged Hollow Slab Beam Bridge that transverse prestress is reinforced is specific as follows:

1. the calculating of vertical cross stiffness is supposed:

The hinged lateral rigidity of bridge that transverse prestress is reinforced can be similar to by up and down solid, the cross section of middle hollow position and the weighted mean in cross section, solid place and calculate the horizontal bending rigidity EJy of its bridge unit and antitorque moment of inertia GJty, that is: the width of (width of complete solid place rigidity * correspondence+maximum hollow position rigidity of section * hollow parts width)/plate; And vertical bending rigidity of bridge remains unchanged, and namely adopts vertical bending rigidity of former plate-girder cross section, and divided by the width of monolithic plate-girder.

2. the analysis of design internal force: with its by 1 hypothesis analogy for behind the orthotropic plate, to freely-supported the analogy orthotropic plate can set up the differential equation of orthotropic plate, find the solution the internal force such as bending and shearing of the both direction of its plate of calculating with the progression classification.Also can obtain relevant parameter alpha, θ etc. by existing G-M method, its load cross direction profiles of computation of table lookup, and then analytical calculation provides its design internal force.

Compared with prior art, the present invention has following beneficial effect:

1. the design flexibility method of the hinged Hollow Slab Beam Bridge of transverse prestress reinforcing of the present invention can comparatively accurately be simulated and the design analysis evaluation the bridge force-bearing characteristics after reinforcing, avoid the process of the modeling Analysis of complexity, and convenient and practical.

2. the internal force result of calculation that provides of the design flexibility method of the hinged Hollow Slab Beam Bridge reinforced of transverse prestress of the present invention is calculated the slightly high of gained than numerical computation method, is used for bridge strengthening and calculates and make bridge that more sufficient safety stock be arranged.

By with numerical computation method result's comparison, the internal force that design flexibility method of the present invention not only is applicable to the reinforcement bridge of the Scheme of Strengthening one among Fig. 1 calculates, the internal force that equally also is applicable to the reinforcement bridge of the Scheme of Strengthening two among Fig. 3 calculates.

Description of drawings

Fig. 1 is the cross-sectional drawing of hinged Hollow Slab Beam Bridge first embodiment of transverse prestress reinforcing of the present invention.

Fig. 2 is the skiagraph of hinged Hollow Slab Beam Bridge first embodiment of transverse prestress reinforcing of the present invention.

Fig. 3 is the cross-sectional drawing of hinged Hollow Slab Beam Bridge second embodiment of transverse prestress reinforcing of the present invention.

Fig. 4 is the skiagraph of hinged Hollow Slab Beam Bridge second embodiment of transverse prestress reinforcing of the present invention.

Fig. 5 is the schematic diagram of the deck paving reinforcing bar of the hinged Hollow Slab Beam Bridge reinforced of transverse prestress of the present invention.

Fig. 6 is the practical structures figure of hinged Hollow Slab Beam Bridge of the present invention.

Fig. 7 is the schematic diagram that Fig. 6 is modeled to the analogy orthotropic plate.

The specific embodiment

See also Figure of description 1 to shown in the accompanying drawing 7, the hinged Hollow Slab Beam Bridge that a kind of transverse prestress is reinforced, it is comprised of several parts such as concrete hollow slab girder 1, hinge seam 2, transverse prestressed reinforcing steel bar 3, deck paving of concrete 4, deck paving reinforcing bar 5, curb girder anchoring system 6, the tired pre-stressed steel pipe 7 of anti-corrosion and prestress steel pipe fixing devices 8.

And because the effect of transverse prestressed reinforcing steel bar 3, bridge after the reinforcing is produced at form of structure, loading characteristic to be changed, can transmit simultaneously transverse shearing force and moment of flexure between plate-girder, the increase of lateral stiffness so that load not only in the vertical, spread in the horizontal simultaneously, therefore, need to design internal force analysis to the bridge after reinforcing calculates.

The hinge that the present invention reinforces transverse prestress is stitched the whole analogy of Hollow Slab Beam Bridge and is desirable orthotropic plate, has proposed to design the method that this type of reinforces the internal force analysis of rear beam bridge, and it comprises the steps:

1), the calculating of vertical cross stiffness:

The lateral stiffness of reinforcement bridge can be similar to by the weighted mean of solid, middle hollow cross section and solid section up and down and calculate it along the bridge longitudinally horizontal bending rigidity EJy of unit and antitorque moment of inertia GJty, that is: the width of (width of complete solid place rigidity * correspondence+maximum hollow position rigidity of section * hollow parts width)/plate; And vertical bending rigidity of bridge remains unchanged, and namely adopts vertical bending rigidity of former plate-girder cross section, and divided by the width of monolithic plate-girder;

2), reinforce the calculation procedure of rear design internal force:

A. computational geometry characteristic;

According to the method computing board of step 1) in length and breadth to the bending resistance moments of inertia, the antitorque moments of inertia and than the wide bending resistance moments of inertia of endorsement, the antitorque moments of inertia;

B. ask parameter alpha, θ;

，

Wherein ,

,

,

Be respectively vertical bending resistance moments of inertia of every meter width, the antitorque moments of inertia, laterally the bending resistance moments of inertia, the antitorque moments of inertia;

C. calculate the horizontal line coordinates that affects of each plate-girder;

(1) with the θ value of having tried to achieve, with reference to the value of locating influence coefficient K1 and K0 on the G-M method nomogram with beam position, the realistic border of interpolation method;

(2) with α value and formula K α=K0+

(K1-K0) interpolation is tried to achieve K α;

(3) count n with girder and affect line coordinates except K α namely gets; Or directly adopt the orthotropic plate equation of analogy to find the solution;

D. calculate Load Transverse Distribution or the design internal force of each plate-girder;

Affect line by horizontal least favorable location arrangements load, thereby calculating Load Transverse Distribution or the design internal force of each plate-girder.

The above specific embodiment only is the preferred embodiment of this creation, not in order to limiting this creation, all in this creation spirit and principle within make any modification, be equal to replacement, improvement etc., all should be included within the protection domain of this creation.

Claims (1)

1. the design flexibility method of the hinged Hollow Slab Beam Bridge reinforced of transverse prestress is characterized in that:

1), the calculating of vertical cross stiffness:

The lateral stiffness of reinforcement bridge can be similar to by the weighted mean of solid, middle hollow cross section and solid section up and down and calculate it along the bridge longitudinally horizontal bending rigidity EJy of unit and antitorque moment of inertia GJty, that is: the width of (width of complete solid place rigidity * correspondence+maximum hollow position rigidity of section * hollow parts width)/plate; And vertical bending rigidity of bridge remains unchanged, and namely adopts vertical bending rigidity of former plate-girder cross section, and divided by the width of monolithic plate-girder;

2), reinforce the calculation procedure of rear design internal force:

A. computational geometry characteristic;

According to the method computing board of step 1) in length and breadth to the bending resistance moments of inertia, the antitorque moments of inertia and than the wide bending resistance moments of inertia of endorsement, the antitorque moments of inertia;

B. ask parameter alpha, θ;

，

Wherein,

,

,

,

Be respectively vertical bending resistance moments of inertia of every meter width, the antitorque moments of inertia, laterally the bending resistance moments of inertia, the antitorque moments of inertia;

C. calculate the horizontal line coordinates that affects of each plate-girder;

(1) with the θ value of having tried to achieve, with reference to the value of locating influence coefficient K1 and K0 on the G-M method nomogram with beam position, the realistic border of interpolation method;

(2) with α value and formula K α=K0+

(K1-K0) interpolation is tried to achieve K α;

(3) count n with girder and affect line coordinates except K α namely gets; Or directly adopt the orthotropic plate equation of analogy to find the solution;

D. calculate Load Transverse Distribution or the design internal force of each plate-girder;

Affect line by horizontal least favorable location arrangements load, thereby calculating Load Transverse Distribution or the design internal force of each plate-girder.

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