CN104514202B - A kind of Single column pier beam bridge antidumping reinforcement means - Google Patents

Abstract

The invention discloses a kind of Single column pier beam bridge antidumping reinforcement means, comprise the steps: that (1) determines antidumping side and side of toppling for default load situation, and set load desired value of toppling；(2) the moment state equation of critical state of toppling is built according to described load desired value of toppling；(3) according to the distance between size or the anti-torsional bearing of the bearing of described moment state equation regulation Single column pier beam bridge to reinforce Single column pier beam bridge.The reinforcement means of the Single column pier beam bridge of the present invention is simple, be easily achieved, and just can complete to reinforce by changing supporting stand size, improve the resistance to capsizing of Single column pier beam bridge.

Description

A kind of Single column pier beam bridge antidumping reinforcement means

Technical field

The present invention relates to civil engineering technology, be specifically related to a kind of Single column pier beam bridge antidumping reinforcement means.

Background technology

The reason of bridge collapse accident includes that construction quality is not enough, designs unreasonable, overload of vehicle, shock With collapsing that other are caused by natural conditions.In succession the collapsing of Single column pier beam bridge the most in recent years, draws Play society's extensive concern.

At present, domestic Bridge Design personnel bending resistance, shear-carrying capacity and agent on crack resistance of concrete to superstructure Fragility can heavier regard, and in the case of meeting code requirement, has bigger redundancy.But to bridge Lateral stability and toppling collapse and lack necessary attention, even if consider topple stable, the most mostly end Whether bearing comes to nothing as evaluating the sole indicator that bridge topples, it is impossible to consider superstructure deadweight right The impact of antidumping, just buries potential safety hazard in the design phase.Single column pier beam bridge is based on by curved master Beam, as the bridge of supporting member, is mainly made up of superstructure and substructure, its superstructure master Box type girder to be included (i.e. box beam), bearing, deck paving, drainage system, guard rail；Bottom Structure mainly includes abutment, bridge pier, basis.Single column pier beam bridge two ends use twin shaft pier (to include two also The bridge pier of row), twin shaft pier is provided with on each pier an anti-torsional bearing, centre uses Single column pier, often A bearing it is provided with on individual pier.Two anti-torsional bearing on commonly referred to as in twin shaft pier are same to antitorque Seat.

For increasing the resistance to capsizing of Single column pier beam bridge, twin shaft pier can be inserted at Single column pier interval, i.e. remove From beginning to end outside two ends, mid portion is also distributed twin shaft pier.

In the standard of highway bridge that China is existing, not yet bridge structure overturning stability is made and clearly advising Fixed.3.5.8 bar and " highway reinforced concrete in " highway bridge and culvert design general specification " (JTGD60-2004) Soil and prestressed concrete bridge contain design specification " 9.7.4 bar the most only forbids bridge in (JTGD62-2004) The description of seat empty.The Ministry of Railways's " railway bridges and culverts reinforced concrete and prestressed concrete structure design rule Model " under 4.1.1 rules and regulations are scheduled on the most dangerous combination effect calculating load in (TB10002.3-2005), spanning The horizontal safety factor on toppling stability of structure is no less than 1.3.And although existing urban bridge design specification proposes Ensure the requirement of bridge stability in the large, but do not provide clear and definite Method for Checking and respective standard.Zhejiang Department of Communications of Shanxi Province proposes in " about only columnar pier bridge stability sex chromosome mosaicism informal discussion meeting summary ", in reality In the computational analysis of border in addition to 1.3 times of lane loads of definition, 1.2 times of vehicular loads of definition are as inclining further Cover check load, whether occur that negative reaction judges the antidumping performance of bridge structure by bearing.At ferrum In road and bridge beam, overload the most serious；But in highway bridge, along with the fast development of equipment manufacture, Overload of vehicle 2-3 times is relatively conventional.According to Reliability Theory, by partial safety factor to strength of materials reduction And external load is amplified, the actual bending resistance of structure or shear-carrying capacity are up to 3-4 times of design load.Therefore, In the design of highway bridge, calculate superstructure and topple that stable only to consider that overload 30% cannot adapt to existing The practical situation of vehicle load；Whether structure is toppled and is occurred negative reaction also to judge only with bearing being worth simultaneously Must discuss；Finally, due to lack effective practical calculation method, engineering staff cannot science quickly sentence Whether bridge cut-off beam topples.

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of Single column pier beam bridge antidumping reinforcement means. Comprise the steps:

(1) determine antidumping side and side of toppling for default load situation, and set the load mesh that topples Scale value；

(2) the moment state equation of critical state of toppling is built according to described load desired value of toppling；

(3) according to the size of the bearing of described moment state equation regulation Single column pier beam bridge or antitorque Distance between Zuo is to reinforce Single column pier beam bridge.The reinforcement means of the Single column pier beam bridge of the present invention is simple, easily In realization, just can complete to reinforce by changing supporting stand size, improve the resistance to capsizing of Single column pier beam bridge.

The present invention regulates the distance between anti-torsional bearing refer in particular to regulate and same resist in anti-torsional bearing two Turn round the distance between bearing.

For ensureing that Single column pier beam bridge does not topples, improving safety, described load desired value of toppling is more than pre- If load situation under topple the load of side, topple under the load situation usually preset side load 1.3～2 times.

During critical state of toppling, (position is nearest for the pivot center of the box beam of Single column pier beam bridge and bearing proximal edge The edge of side) distance equal to the thickness of bearing.

When in the present invention, Single column pier beam bridge reaches seat empty state, for round bearing, rotary shaft Line is positioned at away from the 1/4R of bearing center, and wherein R is the radius of bearing, and for rectangle bearing, (level is cut Face is rectangle) pivot center be positioned at away from the 1/6B of bearing center, B is the width of rectangle.

Carload produces vertical load and moment of torsion under uneven loading action to beam bridge:

When the stabilization sub stage, bridge pier counter-force is by two side ends bearing (anti-torsional bearing) and middle Single column pier associating There is provided；In use due to the load effect of box beam both sides, the pivot center of box beam is gradually deviated from bearing Geometric center, when side-play amount reaches certain degree, there is phenomenon of coming to nothing in antidumping side anti-torsional bearing, Enter transitional stage.

When transitional stage, owing to, before critical state, the bearing of antidumping side (includes the anti-of this side Turn round bearing) already at seat empty state, therefore the bearing of this side will not produce the moment of antidumping；

When toppling the stage, pivot center reaches capacity position, and now the bearing of antidumping side has come to nothing, Lateral deviation of toppling carries the tilting moment produced and carries equal to superstructure (i.e. box beam) dead-load moment, antidumping side Load forces square and side anti-torsional bearing counter-force moment three's sum of toppling, topple side anti-torsional bearing and middle Single column pier The load of opposing vertical (i.e. vertical direction) combined by bearing.

Using moment of toppling as critical state of toppling in the present invention, topple with this critical state Single column pier beam bridge Moment as Single column pier beam bridge antidumping carrying moment.The method of the present invention is when reality is applied, first First determine side of toppling, then using opposite side as antidumping side.

Single column pier beam bridge reach to topple Critical Stability state time, its pivot center is positioned at bearing feather edge 45 ° Upwards toward diffusion position inside bearing.During bearing shape difference, under critical state, the position of pivot center is also Different.

When the bearing cross section of Single column pier beam bridge is circular, described pivot center to bearing (intermediate support, Non-anti-torsional bearing) distance at edge is equal to the thickness of bearing.When the bearing cross section of Single column pier beam bridge is rectangle Time, the distance at described pivot center to bearing (intermediate support, non-anti-torsional bearing) edge is equal to bearing Thickness.

The moment state equation of described critical state of toppling is as follows:

L_R=L_O,

Wherein, L_RResistance to tipping moment under critical state of toppling:

L_OFor tilting moment desired value, according to toppling, load desired value is calculated.

Described tilting moment L under critical state of toppling_RAccording to formula:

$L_R=\underset{i=1}{\overset{n}{\Σ}}{P}_A^i\×l_A^i+\underset{j=1}{\overset{m}{\Σ}}{P}_B^j\×l_B^j+q_G\×l_0\×l_q,$

It is calculated, wherein,For antidumping side i-th load,For anti-under default load situation Toppling the i-th load center, the side distance to pivot center, m is antidumping side under default load situation Load number；

For the counter-force of the side jth anti-torsional bearing that topples under default load situation,For default load In the case of topple the jth anti-torsional bearing center, the side distance to pivot center, n is default load situation Under topple the number of anti-torsional bearing of side；

q_GFor the line severe of box beam, l₀For box beam across footpath, l_qFor box beam centrage and described pivot center Distance in the horizontal direction.

Single column pier beam bridge rotates under uneven loading action, and now bridge does not occurs overturning, according to inclining Cover moment and calculate the axis that topples (i.e. pivot center) of Single column pier beam bridge equal to the principle of resistance to tipping moment.

For beam bridge, load is usually automobile,For the gravity of the i-th automobile of antidumping side, It is calculated by gravity formulat according to quality.

In the present invention calculate linear type Single column pier beam bridge time, its topple critical state time each anti-torsional bearing Counter-force can be calculated by continuous beam computational methods.

In the present invention, the value of m and n changes along with practical situations.

Middle Single column pier produces vertical counter-force and the skid resistance along box beam bottom surface to box beam, and it makes a concerted effort logical Crossing pivot center, moment is zero.Thus can obtain, along with the increasing of unbalance loading, pivot center is gradually toward load Active side moves, tilting moment by end bearing counter-force, the deadweight of box beam and be positioned at the load of antidumping side and carry Supply.

In actual use, the load of Single column pier beam bridge both sides can change, in the present invention fully In view of the loads change of antidumping side, the carrying moment of the antidumping side that can the most accurately determine.

As preferably, described tilting moment desired value L_OAccording to formula:

$L_O=\underset{t=1}{\overset{T}{\Σ}}{P}_O\×l_o^t$

It is calculated, wherein P_OFor load desired value of toppling,For load center and the described rotary shaft of toppling Line distance in the horizontal direction, T is the number of load of side of toppling.

In heretofore described step (3), the size of the bearing of regulation Single column pier beam bridge includes increasing bearing Radius, the thickness of reduction bearing.When reinforcing Single column pier beam bridge, prioritizing selection increases the radius of bearing, Then reduce the thickness of bearing, finally consider further that increase is same to the distance between anti-torsional bearing.

Size range of accommodation is between 10～80% of bearing original depth in actual applications, the tune of radius Adjusting range is R～R_d, wherein R_dFor bridge pier radius.

Not making specified otherwise, two anti-torsional bearing being positioned at defined in the present invention on same bridge pier are same To anti-torsional bearing.

If the present invention (includes between the thickness of bearing and radius, and anti-torsional bearing with three variablees of time-varying Distance), the load that can make to topple improves more, i.e. improves resistance to capsizing, can be according to specifically used Situation formulates Scheme of Strengthening flexibly.

Compared with prior art, the reinforcement means of the Single column pier beam bridge of the present invention is simple, be easily achieved, only Only just complete to reinforce by change supporting stand size, improve the resistance to capsizing of Single column pier beam bridge.

Accompanying drawing explanation

Fig. 1 is that the Single column pier beam bridge of the present embodiment is in the generalized section of head end when toppling critical state；

Fig. 2 is that the Single column pier beam bridge of the present embodiment is in cuing open at any bridge pier in the middle of when toppling critical state Face schematic diagram；

Fig. 3 is to strengthen supporting stand size the load of bridge antidumping is affected figure；

Fig. 4 is to reduce bearing thickness the load of bridge antidumping is affected figure；

What Fig. 5 was the spacing increasing end anti-torsional bearing on the load of bridge antidumping affects figure.

Detailed description of the invention

Describe the present invention below in conjunction with the drawings and specific embodiments.

The present embodiment calculates as a example by the light of spring ramp bridge of Shangyu, Zhejiang this Single column pier beam bridge antidumping carrying Moment.

This beam bridge uses unidirectional two-way traffic (track, one, each direction), cross section width 8m, and box section has Body size: bridge pier diameter 1.1m, top rake 3.5%, each bridge pier sets diameter D=600mm, thickness The bearing of h=150mm, wherein head and the tail two ends are anti-torsional bearing, same antitorque in anti-torsional bearing two Distance l=2.1m between bearing, bridge pier distance box beam lower flange edge 0.4m.

The reinforcement means of the Single column pier beam bridge of the present embodiment, comprises the steps:

(1) determine antidumping side and side of toppling for default load situation, and set the load mesh that topples Scale value；

The load situation preset in the present embodiment is as follows:

4 overload carload lots are respectively 28.52t, 124.44t, 125.6t and 110.73t, and light car exists Inner side, three loaded vehicle pass through with relatively low velocity from the side in outside.

The present embodiment determining, with side, light car place for antidumping side, side, three loaded vehicle places is side of toppling.

3 carloads of side of toppling are 1.46m away from box beam centre distance, 1 of antidumping side Automobile distance box beam center is about 1.64m.Carload is according to (JTG D60-2004 highway bridge and culvert designs General specification) apply.The load of each automobile of side of now toppling is 120 tons, for ensureing not topple, The corresponding automotive dead weight desired value set as 165 tons, load desired value P of i.e. toppling_O=1617KN.

Set the position of topple critical state and now pivot center: set only post when toppling critical state The pivot center of the box beam of pier beam bridge is equal to the thickness of bearing with the antermarginal distance of bearing.

Fig. 1 and Fig. 2 is the state signal that in the present embodiment, Single column pier beam bridge is in when toppling critical state Figure, its center line A is the centrage of critical state box beam of toppling, and line B is pivot center, big in Fig. 2 Circle region is the enlarged drawing in roundlet region.

As in figure 2 it is shown, the present embodiment determining, under critical state of toppling, the pivot center of box beam is to support edges Distance a=h of edge, wherein h is bearing thickness (150mm).

(2) the moment state equation of critical state of toppling is built according to load desired value of toppling；

L_R=L_O,

Wherein, L_RResistance to tipping moment under critical state of toppling:

$L_R=\underset{i=1}{\overset{n}{\Σ}}{P}_A^i\×l_A^i+\underset{j=1}{\overset{m}{\Σ}}{P}_B^j\×l_B^j+q_G\×l_0\×l_q,$

It is calculated, wherein,For the load of antidumping side i-th load, as it is shown in figure 1,For Under the load situation preset, i-th load center, antidumping side is to the distance of pivot center, and n is default The load number of antidumping side under load situation；

Calculate according to equation below:

$l_A^i=L_A^i+(\frac{D}{2}-h)$

Wherein,For the distance at the automobile distance box beam center of antidumping side, the present embodiment is 1.64m。

For the counter-force of the side jth anti-torsional bearing that topples under default load situation, as it is shown in figure 1,For Toppling the jth anti-torsional bearing center, the side distance to pivot center under the load situation preset, m is default Load situation under topple the number of anti-torsional bearing of side；

Calculate according to equation below:

$l_B^j=L_B^j-(\frac{D}{2}-h)$

Wherein,For the distance at the anti-torsional bearing centre distance box beam center of side of toppling, in the present embodiment For 1.05m.

q_GFor the line severe of box beam, l₀For box beam across footpath, as it is shown in figure 1, l_qFor box beam centrage with Described pivot center distance in the horizontal direction.

l_qCalculate according to equation below:

$l_q=\frac{D}{2}-h.$

In the present embodiment, antidumping side automobile quantity is 1, i.e. n=1, and quality is 28.52t.

The present embodiment m=2, the counter-force of each anti-torsional bearing uses continuous beam computational methods to obtain, the most such as Under:

Arrange vehicular load according to the actual loading position that topples of light of spring bridge, obtain the load that topples, then use Continuous beam computational methods calculate the counter-force of each bearing (anti-torsional bearing) under this load action that topples.

L_OFor tilting moment desired value, available equation below is calculated:

$L_O=\underset{t=1}{\overset{T}{\Σ}}{P}_O\×l_o^t$

It is calculated, wherein P_OFor load desired value of toppling,For load center and the described rotary shaft of toppling Line distance in the horizontal direction, T is the number (T=3 in the present embodiment) of load of side of toppling.

Calculate according to equation below:

$l_O^t-L_O^t-(\frac{D}{2}-h)$

Wherein,For the distance at the automobile distance box beam center of side of toppling, the present embodiment is about 1.46m。

(3) between size or the anti-torsional bearing according to the bearing of moment state equation regulation Single column pier beam bridge Distance to reinforce Single column pier beam bridge.

When Fig. 3 is for fixing anti-torsional bearing spacing and bearing thickness, strengthen bearing diameter to bridge antidumping Load (maximum that can bear topple load) affect figure；Fig. 4 is for fixing anti-torsional bearing spacing and props up During seat diameter, reducing bearing thickness affects figure to the load of bridge antidumping；Fig. 5 is that hold-down support is thick When degree and diameter, the spacing (i.e. vertical displacement) of the increase end anti-torsional bearing load to bridge antidumping Affect figure.Can be seen that increasing bearing diameter, or reduce bearing thickness, or increase end anti-torsional bearing Spacing can increase the bearing capacity of toppling that bridge is anti-.

If anti-torsional bearing spacing l of anchor portion (two ends from beginning to end), and change supporting stand size, now lead to Cross mechanics and geometrical calculation obtain:

$P_A^1=28.52\×9.8kN,$

$l_A^1=(1.64+\frac{D}{2}-h)m,$

$P_B^1=1038kN,P_B^2=1012kN,$

$l_B^1=l_B^2=\[\frac{2.1}{2}-(\frac{D}{2}-h)\]m,$

q_G=130kN/m,

$l_q=(\frac{D}{2}-h)m;$

The most now limit resistance to tipping moment (being i.e. in the resistance to tipping moment of critical state of the toppling) L of beam bridge_R For:

$L_R=\underset{i=1}{\overset{n}{\Σ}}{P}_A^i\×l_A^i+\underset{j=1}{\overset{m}{\Σ}}{P}_B^j\×l_B^j+q_G\×l_0\×l_q=2610.87+13829.50\×(\frac{D}{2}-h)kN\·m$

Owing to parking stall, three, side of toppling is on same track, then all cars in the side distance to pivot center of toppling The most equal, the present embodiment is obtained by geometrical calculation:

$l_o^1=l_o^2=l_o^3=\[1.46-(\frac{D}{2}-h)\]m;$

Then it is calculated tilting moment desired value L_O:

$L_O=\underset{t=1}{\overset{T}{\Σ}}{P}_O\×l_o^t=\[7082.46-4851(\frac{D}{2}-h)\]kN\·m.$

Substitute in moment state equation and solve and obtain:

$\frac{D}{2}-h\≈0.24m$

As hold-down support thickness h=0.15m, during distance l=2.1m between anti-torsional bearing, with bearing diameter D As unknown quantity, substitute into moment state equation, solve and obtain bearing diameter D=0.78m, i.e. strengthen bearing When diameter is to 0.78m, can make bridge antidumping bearing capacity by original 120 tons (practical limit load by Destory the scene actual measurement, and average per car is 120 tons) increase to 165 tons.

As hold-down support diameter D=0.6m, during distance l=2.1m between anti-torsional bearing, with bearing thickness h As unknown quantity, substitute into moment state equation, solve and obtain bearing thickness h=0.06m, it can thus be appreciated that subtract When little bearing thickness is to 0.06m, also can improve bridge antidumping bearing capacity to 165 tons.

If hold-down support size, and change anti-torsional bearing spacing l at end (two ends from beginning to end), now by Mechanics and geometrical calculation obtain:

$P_A^1=28.52\×9.8kN,$

$l_A^1=1.79m,$

q_G=130kN/m,

l_q=0.15m,

$P_B^1=1038kN,P_B^2=1012kN;$

The most now limit resistance to tipping moment (being i.e. in the resistance to tipping moment of critical state of the toppling) L of beam bridge_R For:

$L_R=\underset{i=1}{\overset{n}{\Σ}}{P}_A^i\×l_A^i+\underset{j=1}{\overset{m}{\Σ}}{P}_B^j\×l_B^j+q_G\×l_0\×l_q=500.30+(1038+1012)\×l_B^j+2340.00kN\·m$

Owing to parking stall, three, side of toppling is on same track, then all cars in the side distance to pivot center of toppling The most equal, the present embodiment is obtained by geometrical calculation,Then it is calculated the power of toppling Square desired value L_O:

$L_O=\underset{t=1}{\overset{T}{\Σ}}{P}_O\×l_o^t=6354.81kN\·m.$

Substitute in moment state equation and obtain:

$2840.30+2050\×l_B^j=6354.81;$

Solve further and obtain:

$l_B^j\≈1.71m,$

Then $l=2\×(l_B^j+R-h)=3.72m,$

The anti-torsional bearing spacing at two ends will increase to 3.72m, the load that topples of this Single column pier beam bridge can be made to carry Up to 165 tons.

Technical scheme and beneficial effect have been carried out in detail by above-described detailed description of the invention Explanation, it should be understood that the foregoing is only presently most preferred embodiment of the invention, is not limited to this Bright, all made in the spirit of the present invention any amendment, supplement and equivalent etc., all should wrap Within being contained in protection scope of the present invention.

Claims (6)

1. a Single column pier beam bridge antidumping reinforcement means, it is characterised in that comprise the steps:

(1) determine antidumping side and side of toppling for default load situation, and set the load mesh that topples Scale value；

(2) the moment state equation of critical state of toppling is built according to described load desired value of toppling；

The pivot center of the box beam of Single column pier beam bridge and the antermarginal distance of bearing etc. during critical state of toppling Thickness in bearing；

(3) according to the size of the bearing of described moment state equation regulation Single column pier beam bridge or antitorque Distance between Zuo is to reinforce Single column pier beam bridge.

2. Single column pier beam bridge antidumping reinforcement means as claimed in claim 1, it is characterised in that institute The load desired value of toppling stated is 1.3～2 times of side load of toppling under default load situation.

3. the Single column pier beam bridge antidumping reinforcement means as described in any one in claim 1～2, its Be characterised by, described in the topple moment state equation of critical state as follows:

L_R=L_O,

Wherein, L_RResistance to tipping moment under critical state of toppling:

L_OFor tilting moment desired value, according to toppling, load desired value is calculated.

4. Single column pier beam bridge antidumping reinforcement means as claimed in claim 3, it is characterised in that institute Resistance to tipping moment L under the critical state of toppling stated_RAccording to formula:

$L_R=\underset{i=1}{\overset{n}{\Σ}}{P}_A^i\×l_A^i+\underset{j=1}{\overset{m}{\Σ}}{P}_B^j\×l_B^j+q_G\×l_0\×l_q,$

It is calculated, wherein,For the i-th load of antidumping side under default load situation,For Under the load situation preset, i-th load center, antidumping side is to the distance of pivot center, and n is default The load number of antidumping side under load situation；

For the counter-force of the side jth anti-torsional bearing that topples under default load situation,For default load In the case of topple the jth anti-torsional bearing center, the side distance to pivot center, m is default load situation Under topple the number of anti-torsional bearing of side；

q_GFor the line severe of box beam, l₀For box beam across footpath, l_qFor box beam centrage and described pivot center Distance in the horizontal direction.

5. Single column pier beam bridge antidumping reinforcement means as claimed in claim 3, it is characterised in that institute Tilting moment desired value L stated_OAccording to formula:

$L_O=\underset{t=1}{\overset{T}{\Σ}}{P}_O\×l_o^t$

It is calculated, wherein P_OFor load desired value of toppling,For load center and the described rotary shaft of toppling Line distance in the horizontal direction, T is the number of load of side of toppling.

6. Single column pier beam bridge antidumping reinforcement means as claimed in claim 3, it is characterised in that institute State the size of the bearing of regulation Single column pier beam bridge in step (3) to include increasing bearing radius, reducing bearing Thickness.