CN104330212A - Swiveling construction weighing method for flat hinges - Google Patents
Swiveling construction weighing method for flat hinges Download PDFInfo
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- CN104330212A CN104330212A CN201410540161.XA CN201410540161A CN104330212A CN 104330212 A CN104330212 A CN 104330212A CN 201410540161 A CN201410540161 A CN 201410540161A CN 104330212 A CN104330212 A CN 104330212A
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Abstract
The invention discloses a swiveling construction weighing method for flat hinges. The method comprises the following steps: a dial indicator is arranged at each of the left and right ends of an area, where a flat hinge are arranged, between upper and lower rotary tables; the compression difference between the two ends of an upper flat hinge of the flat hinge is obtained through measurement by the dial indicators, and the counter force being moment at the flat hinge is calculated according to the compression difference; and the eccentricity value of a swinging beam segment is calculated according to the counter force being moment at the flat hinge. By adopting the swiveling construction weighing method for flat hinges provided by the invention, weighing of flat hinge swiveling construction can be realized.
Description
Technical field
The present invention relates to science of bridge building technology, particularly a kind of rotator construction Weighing method of flat hinge.
Background technology
Crossing over the busy railway of operation, highway is when carrying out bridge construction, and erection by swing construction, due to minimum to the Influence to operation interference of existing line, therefore obtain and applies more and more widely.The key of erection by swing construction is the stable of structure in work progress.Owing to may occur in work progress building error, actual center gravity and design gravity may there are differences, therefore in order to ensure bridge rotate before tear safety in frame process open and the carrying out smoothly of process of turning, turn last as must carry out operation that rotating body beam is weighed, the fundamental purpose of this weighing operation measures the centre of gravity place of cant beam body, thus carry out counterweight where necessary to ensure that the position deviation of rotating body beam section center of gravity is in safe range.
At present, the turning hinge form of rotating body beam mainly contains ball pivot peace hinge two kinds.The surface of contact of the upper lower rotary table of ball pivot is sphere form, and the upper lower rotary table of flat hinge is plane form.Because the surface of contact of ball pivot is sphere form, and when sphere occurs to slide, turning hinge place counter-force moment M z is fixed value, therefore the weighing than being easier to of ball pivot.But, the weighing operation more complicated of flat hinge, reason is that turning hinge place counter-force moment M z distributes relevant to deadweight eccentric load, in actual application environment, due to reasons such as template deviation and cast, deadweight eccentric load distribution form is uncertain, so in current flat hinge rotator construction, rotator construction weighing operation for flat hinge mostly is and judges qualitatively, and cannot obtain eccentricity value accurately to instruct flat hinge rotator construction and counterweight.But relative to ball pivot, flat hinge has manufacture, handling ease, be convenient to the features such as transport, installation, be applicable to large-tonnage rotator construction, therefore, find and a kind ofly accurately can carry out method that flat hinge rotator construction weighs and to have become in this area a technical matters urgently to be resolved hurrily.
Summary of the invention
In view of this, the invention provides a kind of rotator construction Weighing method of flat hinge, thus can effectively realize weighing to flat hinge rotator construction.
Technical scheme of the present invention is specifically achieved in that
A rotator construction Weighing method for flat hinge, the method comprises:
A, two ends, left and right between the upper and lower rotating disk arranging flat hinge arrange a dial gauge respectively;
B, the decrement at upper flat hinge two ends being obtained flat hinge by described dial gauge measurement are poor, and according to the counter-force moment of flexure at the flat hinge place of described decrement difference calculating;
C, counter-force moment of flexure according to flat hinge place, calculate the eccentricity value of rotating body beam section.
Preferably, described step B comprises;
Read the reading of two dial gauges, obtain the reading variable quantity of two dial gauges in two different time points;
The rotational angle of top rotary table generation is calculated according to described reading variable quantity;
The distortion of semicircle centre of form place is calculated according to the rotational angle that described top rotary table occurs;
According to described semicircle centre of form place distortion, calculate the power at semicircle centre of form place;
According to the power at above-mentioned semicircle centre of form place, calculate the counter-force moment of flexure at flat hinge place.
Preferably, the computing formula of the rotational angle of described top rotary table generation is:
△θ＝(△1-△2)/2/D
Wherein, △ θ is the rotational angle that top rotary table occurs; △ 1 and △ 2 is the reading variable quantity of two dial gauges; D is the radius of top rotary table.
Preferably, the computing formula of described semicircle centre of form place distortion is:
△h＝4R/3π*(△1-△2)/2/D
Wherein, △ h is the distortion of semicircle centre of form place, and R is the radius of upper flat hinge and lower flat hinge.
Preferably, the computing formula of the power at described semicircle centre of form place is:
△F＝△h/H*E*A
Wherein, △ F is the power at semicircle centre of form place, and H is the original thickness of slide plate, and E is the elastic modulus of slide plate is that A is the total area of slide plate.
Preferably, the computing formula of the counter-force moment of flexure at described flat hinge place is:
Mz＝2*△F*4R/3π
Wherein, Mz is the counter-force moment of flexure at described flat hinge place.
Preferably, described step C comprises:
According to the counter-force calculation of Bending Moment rotating body beam section eccentric bending moment at flat hinge place;
The eccentricity value of rotating body beam section is calculated according to described rotating body beam section eccentric bending moment.
Preferably, the computing formula of described rotating body beam section eccentric bending moment is:
Mg＝Mz+(F1-F2)L
Wherein, Mg is rotating body beam section eccentric bending moment, F1 and F2 is two rigid support counter-forces at rotating body beam two ends, and F1>F2; L is side, the section of turning girder turning hinge center length.
Preferably, the computing formula of the eccentricity value of described rotating body beam section is:
e＝Mg/N
Wherein, e is the eccentricity value of rotating body beam section, and N is the weight of rotating body beam section.
As above visible, the rotator construction Weighing method of the flat hinge in the application of the invention, can realize weighing to flat hinge rotator construction.And the rotator construction Weighing method of the flat hinge provided in the present invention is simple to operate, and required instrument and equipment is few, only need dial gauge to carry out displacement measurement, construction survey is simple.In addition, also requirement of engineering can be met completely by the measuring accuracy of the rotator construction Weighing method gained of above-mentioned flat hinge.
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of the rotator construction Weighing method of flat hinge in the embodiment of the present invention;
Fig. 2 is the principle schematic that the flat hinge rotator construction in the embodiment of the present invention is weighed.
Fig. 3 is the schematic flow sheet of the rotator construction Weighing method of flat hinge in the embodiment of the present invention one.
Embodiment
For making object of the present invention, technical scheme and advantage clearly understand, to develop simultaneously embodiment referring to accompanying drawing, the present invention is described in more detail.
Present embodiments provide a kind of rotator construction Weighing method of flat hinge, thus can effectively realize weighing to flat hinge rotating body beam section.
Fig. 1 is the schematic flow sheet of the rotator construction Weighing method of flat hinge in the embodiment of the present invention.As shown in Figure 1, the rotator construction Weighing method of the flat hinge in the embodiment of the present invention mainly comprises step as described below:
Step 11, the two ends, left and right between the upper and lower rotating disk arranging flat hinge arrange a dial gauge respectively.
Fig. 2 is the principle schematic that the flat hinge rotator construction in the embodiment of the present invention is weighed.As shown in Figure 2, flat hinge comprises the slide plate 4 between flat hinge 3, lower flat hinge 5 and upper and lower flat hinge.Upper and lower flat hinge is round section, and radius is R, and slide plate 4 is evenly distributed between upper and lower flat hinge.Slide plate 4 is elastic compressible material, and elastic modulus is E, and the total area is A.Be provided with top rotary table 2 on upper flat hinge 3, radius is D, and lower flat hinge 5 is embedded in lower rotary table 6.
Therefore, in order to carry out weighing operation to flat hinge, in this step, a dial gauge 7 can be set the two ends, left and right between top rotary table 2 and lower rotary table 6 respectively.The decrement that described dial gauge 7 may be used for measuring two ends is poor.
Step 12, the decrement being obtained the upper flat hinge two ends of flat hinge by described dial gauge measurement is poor, and calculates the counter-force moment M z at flat hinge place according to measured decrement difference.
In a particular embodiment of the present invention, due in above-mentioned steps 11, the two ends, left and right between upper and lower rotating disk are provided with a dial gauge respectively, therefore.When top rotary table rotates, will there is corresponding change in the reading of dial gauge.So, in this step, above-mentioned dial gauge measurement can be used to obtain the decrement at flat hinge two ends poor.Such as, by reading the reading of two dial gauges, thus obtain reading variable quantity △ 1 and the △ 2 of two dial gauges in two different time points.After measuring the decrement difference obtaining flat hinge two ends, the counter-force moment M z at flat hinge place can be calculated according to measured decrement difference.
For example, in the preferred embodiment, after the reading variable quantity △ 1 getting two dial gauges and △ 2, the rotational angle of top rotary table generation can first be calculated according to above-mentioned reading variable quantity.Such as, the rotational angle that top rotary table occurs can be calculated by formula as described below:
△θ＝(△1-△2)/2/D
After the rotational angle calculating top rotary table generation, the counter-force moment M z at flat hinge place can be calculated according to described rotational angle.
Such as, because semicircle centre of form distance half-breadth is 4R/3 π, the rotational angle that therefore can first occur according to top rotary table calculates semicircle centre of form place distortion △ h:
△h＝4R/3π*(△1-△2)/2/D
According to above-mentioned semicircle centre of form place distortion △ h, the power △ F at semicircle centre of form place can be calculated:
△F＝△h/H*E*A，
Wherein, H is the original thickness of slide plate 4, and E is the elastic modulus of slide plate 4 is that A is the total area of slide plate 4.
Then, according to the power △ F at above-mentioned semicircle centre of form place, the counter-force moment M z at flat hinge place can be calculated:
Mz＝2*△F*4R/3π
As from the foregoing, measuring, the decrement obtaining flat hinge two ends is poor, can calculate the counter-force moment M at flat hinge place according to measured decrement difference.
In addition, in the inventive solutions, other mode also can be used to calculate the counter-force moment M at flat hinge place according to measured decrement difference, and concrete computing method do not repeat them here.
Step 13, according to the counter-force moment M z at flat hinge place, calculates the eccentricity value of rotating body beam section.
Such as, in the preferred embodiment, first rotating body beam section eccentric bending moment Mg can be calculated according to the counter-force moment M z at flat hinge place.For example, formulae discovery Mg as described below can be used:
Mg＝Mz+(F1-F2)L
Wherein, F1 and F2 is two rigid support counter-forces at rotating body beam two ends, and supposes F1>F2; L is side, the section of turning girder turning hinge center length, as shown in Figure 2.
After calculating rotating body beam section eccentric bending moment Mg, the eccentricity value e of rotating body beam section can be calculated according to this rotating body beam section eccentric bending moment Mg.Such as, formulae discovery e as described below can be used:
e＝Mg/N，
Wherein, N is the weight of rotating body beam section.
As from the foregoing, by above-mentioned step 11 ~ 13, the eccentricity value e of rotating body beam section can be calculated, thus the rotator construction completing flat hinge is weighed.
Below, for a specific embodiment, technical scheme of the present invention will be introduced in more detail.
Embodiment one: the rotator construction Weighing method of the flat hinge on cable-stayed bridge.
Fig. 3 is the schematic flow sheet of the rotator construction Weighing method of flat hinge in the embodiment of the present invention one.As shown in Figure 3, in the present embodiment, the rotator construction Weighing method of the flat hinge on described cable-stayed bridge mainly comprises step as described below:
Step 301, sets up full framing, arranges beam-ends rigid support 8 at the two ends of full framing; The cast-in-place section of turning girder 1 and king-tower 10 on full framing and beam-ends rigid support 8.As shown in Figure 2.
Step 302, settles two dial gauges 7 respectively at the two ends, left and right of top rotary table 2 and lower rotary table 6.As shown in Figure 2.
Step 303, stretching oblique drag-line 9, removes full framing, carries out supplemental support by beam-ends rigid support 8.
Step 304, measures the reading variable quantity of two dial gauges 7, and calculates the counter-force moment M z at flat hinge place according to measured reading variable quantity.
Step 305, according to the counter-force moment M z at flat hinge place, calculates the eccentricity value of rotating body beam section.
Such as, when the pulling force of suspension cable 9 is larger, the section of turning girder 1 and beam-ends rigid support 8 depart from, now Mg=Mz.
And when the pulling force of suspension cable 9 is less, the section of turning girder 1 and beam-ends rigid support 8 do not depart from, then the counter-force can measuring beam rigid support is respectively F1 and F2 (assuming that F1>F2).Now can obtain: Mg=Mz+ (F1-F2) L, wherein, L is side, the section of turning girder turning hinge center length.Then, the eccentricity value e:e=Mg/N of rotating body beam section can be calculated according to Mg.Wherein, N is the weight of rotating body beam section.
In addition, accuracy evaluation can also be carried out to the rotator construction Weighing method of above-mentioned flat hinge.Such as, the measuring accuracy of dial gauge is 0.01mm, and according to the size of the turning hinge of 4 tons, the radius R=2.89m of flat hinge, top rotary table radius D=8m, slide plate original thickness is 13mm, elastic modulus E=345MPa, area A=4.304m2.Therefore, as dial gauge reading variable quantity △ 1-△ 2=0.01mm, the eccentricity value eccentric distance e=0.6mm calculated, can meet construction needs completely.
In summary, the rotator construction Weighing method of the flat hinge in the application of the invention, can realize weighing to flat hinge rotator construction.And the rotator construction Weighing method of the flat hinge provided in the present invention is simple to operate, and required instrument and equipment is few, only need dial gauge to carry out displacement measurement, construction survey is simple.In addition, also requirement of engineering can be met completely by the measuring accuracy of the rotator construction Weighing method gained of above-mentioned flat hinge.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within the scope of protection of the invention.
Claims (9)
1. a rotator construction Weighing method for flat hinge, it is characterized in that, the method comprises:
A, two ends, left and right between the upper and lower rotating disk arranging flat hinge arrange a dial gauge respectively;
B, the decrement at upper flat hinge two ends being obtained flat hinge by described dial gauge measurement are poor, and according to the counter-force moment of flexure at the flat hinge place of described decrement difference calculating;
C, counter-force moment of flexure according to flat hinge place, calculate the eccentricity value of rotating body beam section.
2. method according to claim 1, is characterized in that, described step B comprises;
Read the reading of two dial gauges, obtain the reading variable quantity of two dial gauges in two different time points;
The rotational angle of top rotary table generation is calculated according to described reading variable quantity;
The distortion of semicircle centre of form place is calculated according to the rotational angle that described top rotary table occurs;
According to described semicircle centre of form place distortion, calculate the power at semicircle centre of form place;
According to the power at above-mentioned semicircle centre of form place, calculate the counter-force moment of flexure at flat hinge place.
3. method according to claim 2, is characterized in that, the computing formula of the rotational angle that described top rotary table occurs is:
△θ＝(△1-△2)/2/D
Wherein, △ θ is the rotational angle that top rotary table occurs; △ 1 and △ 2 is the reading variable quantity of two dial gauges; D is the radius of top rotary table.
4. method according to claim 3, is characterized in that, the computing formula of described semicircle centre of form place distortion is:
△h＝4R/3π*(△1-△2)/2/D
Wherein, △ h is the distortion of semicircle centre of form place, and R is the radius of upper flat hinge and lower flat hinge.
5. method according to claim 4, is characterized in that, the computing formula of the power at described semicircle centre of form place is:
△F＝△h/H*E*A
Wherein, △ F is the power at semicircle centre of form place, and H is the original thickness of slide plate, and E is the elastic modulus of slide plate is that A is the total area of slide plate.
6. method according to claim 5, is characterized in that, the computing formula of the counter-force moment of flexure at described flat hinge place is:
Mz＝2*△F*4R/3π
Wherein, Mz is the counter-force moment of flexure at described flat hinge place.
7. method according to claim 6, is characterized in that, described step C comprises:
According to the counter-force calculation of Bending Moment rotating body beam section eccentric bending moment at flat hinge place;
The eccentricity value of rotating body beam section is calculated according to described rotating body beam section eccentric bending moment.
8. method according to claim 7, is characterized in that, the computing formula of described rotating body beam section eccentric bending moment is:
Mg＝Mz+(F1-F2)L
Wherein, Mg is rotating body beam section eccentric bending moment, F1 and F2 is two rigid support counter-forces at rotating body beam two ends, and F1>F2; L is side, the section of turning girder turning hinge center length.
9. method according to claim 8, is characterized in that, the computing formula of the eccentricity value of described rotating body beam section is:
e＝Mg/N
Wherein, e is the eccentricity value of rotating body beam section, and N is the weight of rotating body beam section.
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