CN111549682A - Longitudinal prestress long and short beam division tensioning control method for cantilever construction bridge - Google Patents
Longitudinal prestress long and short beam division tensioning control method for cantilever construction bridge Download PDFInfo
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D21/00—Methods or apparatus specially adapted for erecting or assembling bridges
- E01D21/10—Cantilevered erection
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G21/00—Preparing, conveying, or working-up building materials or building elements in situ; Other devices or measures for constructional work
- E04G21/12—Mounting of reinforcing inserts; Prestressing
- E04G21/121—Construction of stressing jacks
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Abstract
The invention discloses a method for dividing long and short prestressed beams of a cantilever construction bridge into a plurality of longitudinal prestressed beams and a plurality of longitudinal prestressed beams, which comprises the following steps of (1) obtaining parameters and parameter values of the longitudinal prestressed beams of the bridge, changing the designed tension control stress by +/- α%, calculating the elongation value deviation of the steel beams, (2) calculating the tension stress deviation caused by the elongation value error of the unit length of the steel beams, (3) drawing an L-delta sigma relation graph and carrying out curve fitting, wherein the correlation coefficient is more than or equal to 0.98, (4) solving the maximum curvature point or stagnation point of the fitted curve, namely a critical point, and enabling the length L of the corresponding steel beams to correspond to the length L0Critical length as long and short beam division; (5) and (5) providing a prestress tension control criterion based on the threshold value of the critical length. The invention has the beneficial technical effects that the influence of the length difference of the steel bundles on the stress control of the steel bundles is considered, the prestress critical length division method is provided, and the tension control criterion taking the critical length as a threshold value is used for tensioning the longitudinal prestress of the cantilever construction bridgeConstruction provides technical support.
Description
Technical Field
The invention relates to a method for dividing and tensioning long and short beams of longitudinal prestress of a cantilever construction bridge, which is mainly used for guiding the tensioning construction of the longitudinal prestress of the cantilever construction bridge and belongs to the technical field of bridge construction control.
Background
The prestressed concrete box girder bridge with strong terrain adaptability, large spanning capability, mature design and construction technology, reasonable manufacturing cost and attractive appearance is widely adopted in the bridge with the main span of 60-200 m in China, a segmental cantilever casting method is generally adopted for construction, the length of a longitudinal prestressed steel beam is about 10-60-200 m (the main span is equivalent in length), and the bridge has the characteristic of more prestressed steel beam length specifications no matter whether the bridge is bundled in the early stage or the later stage or is directly bundled or bent.
According to incomplete statistics, the existing domestic large-span continuous box girder bridge in service has insufficient effective prestress due to the fact that prestress tension control in construction is not fine, the phenomena of girder body cracking and continuous downwarping in a main span are caused in the operation period, and huge economic loss and serious social influence are caused. In order to ensure the construction safety of the large-span bridge cantilever and the line shape and stress state in the bridge forming process to meet the design expectation, the fine control of the prestress tension is very important.
At present, the "double control" criterion of prestressed tension means that when a prestressed steel beam is tensioned by adopting a stress control method, the elongation value is checked, the difference value between the actual elongation value and the theoretical elongation value is in accordance with the design requirement, the design is random and timed, and the difference value between the actual elongation value and the theoretical elongation value is controlled within 6%; the method is a criterion which takes tensile stress control as a main principle and elongation value control as an auxiliary principle, and the influence of the length difference of the steel bundles on the stress control is not considered. Through the sensitivity analysis of the elongation value error of the prestressed steel bundle to the control stress deviation, the influence of the length difference of the steel bundle on the stress control is found to be not negligible: for short beams, a smaller elongation value error will cause a larger stress variation; for long beams, a smaller stress error will cause a larger elongation value change.
Therefore, how to consider the influence of the length of the steel beam in the control of the longitudinal prestress tension of the bridge, the key point for solving the technical problems is to provide a prestress tension control method which is strong in practicability and more precise and takes the critical length of the steel beam as a threshold value.
Disclosure of Invention
The invention aims to overcome the defects and provide a high-practicability and more precise tensioning control method for dividing the longitudinal prestress long and short beams of the cantilever construction bridge, which is used for guiding the tensioning construction of the longitudinal prestress of the cantilever construction bridge.
In order to solve the problems and achieve the purpose, the invention provides a method for dividing and tensioning long and short beams of longitudinal prestress of a cantilever construction bridge, which is realized by the following technical scheme:
a longitudinal prestress long and short beam division tensioning control method for a cantilever construction bridge comprises the following steps:
(1) obtaining parameters and parameter values of the bridge longitudinal prestress steel beam for calculating the tension elongation value thereof, and defining delta L1The theoretical elongation value of each steel bundle is obtained; design tension control stress sigmaconVariation. + -. α%, definition Δ L2(α) calculating the elongation value deviation delta l of each steel bundle;
(2) defining delta sigma as tensile stress deviation caused by elongation value error of unit length of the steel bundle, and calculating the delta sigma value of each steel bundle;
(3) drawing a relation graph of the length L of the longitudinal prestressed steel beam and delta sigma, namely an L-delta sigma graph; performing curve fitting on the scattered points of the L-delta sigma graph to obtain a fitting curve regression equation and a correlation coefficient R; the correlation coefficient R should be greater than or equal to 0.98;
(4) determining the critical point of the L-delta sigma fitting curve: calculating a curvature function of the L-delta sigma fitting curve according to the regression equation in the step (3), and solving a maximum curvature point or a stagnation point; taking the maximum curvature point or stationary point of the L-delta sigma fitting curve as the critical point, and recording the coordinate (L) of the critical point0,Δσ0) (ii) a Definition of L0Critical length divided for longitudinal prestress long and short beams;
(5) according to the critical length L of the long and short beam division obtained in the step (4)0Taking the tension control threshold value as a longitudinal prestress tension control threshold value, and determining a tension control criterion as follows:
preferably, in the step (1), the deviation Δ l of the elongation value of the steel bundle is calculated by the formula:
in the formula: Δ L2(α) controlling stress σ for design of tensionconElongation of steel bundle varied by + - α%. DELTA.L1The theoretical elongation value of the steel bundle, α the tensile stress variation rate, the integer is not less than 1 and not more than α and not more than 5, the sigma isconControlling stress for design of tension; k is the influence coefficient of local deviation per meter of the pipeline on friction; x is the length of the pipeline from the tensioning end to the calculated cross section; mu is the friction coefficient between the prestressed tendon and the pipeline wall; theta is the sum of included angles from the tensioning end to the tangent of the pipeline part of the calculated section curve; l is the length of the steel bundle; epIs the modulus of elasticity.
Preferably, in the step (2), the tensile stress deviation Δ σ caused by the elongation value error per unit length of the steel bundle is calculated by the formula:
wherein α is tension control stress variation rate, 1 is equal to or more than α is equal to or less than 5, and sigma is an integerconControlling stress for design of tension; and delta l is the elongation value deviation of the steel bundle.
Preferably, in step (3), the function type of the L- Δ σ fitting curve is generally a negative exponential function.
Preferably, in the step (4), the maximum curvature point or stagnation point of the L-delta sigma fitting curve, namely the critical point, is solved, and the corresponding length L of the steel bundle is obtained0Defined as the critical length of the longitudinal pre-stress long and short beam division.
Preferably, in the step (5), the critical length L for dividing the long and short bundles is determined0As a threshold value of longitudinal prestress tension control, determining a tension control criterion as follows: when L is less than or equal to L0In the process, the principle that tension stress control is used as a main principle and elongation value check is used as an auxiliary criterion is adopted; when L > L0And meanwhile, adopting a principle that tension elongation value control is taken as a main principle and stress check is taken as an auxiliary principle.
Preferably, the elongation value is a single-ended elongation value.
Compared with the prior art, the invention has the following beneficial effects: the invention applies a parameter sensitivity analysis method to the prestress tension control technology, and examines the sensitivity degree of the elongation value error of the unit length of the steel beam to the tension stress deviation delta sigma of the steel beam aiming at the steel beams with different length specifications; it is clear that the critical point of the L-delta sigma fitting curve is the maximum curvature point or the stationary point thereof, and the critical point corresponds to the length L of the steel beam0The critical length of the long and short steel bundles is used as the threshold value of the tension control criterion; according to the length L of the steel bundle and the critical length L0The magnitude relation of the tension stress and the tension elongation value determines the criterion that the tension stress control is taken as the main criterion or the tension elongation value control is taken as the main criterion-when L is less than or equal to L0In time, L is sensitive to delta sigma, and a principle that tension stress control is used as a main principle and elongation value check is used as an auxiliary criterion is adopted; when L > L0In time, L is insensitive to delta sigma undertone, and a principle that tension elongation value control is taken as a main principle and stress check is taken as an auxiliary criterion is adopted; the control criterion is more scientific and reasonable, and the prestress tension is more finely controlled. The invention considers the influence of the length difference of the steel bundles on the stress control of the steel bundles, provides a prestress critical length dividing method and uses the critical lengthAnd the tension control criterion with the degree as a threshold value provides technical support for the tension construction of the longitudinal prestress of the cantilever construction bridge.
Drawings
The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings:
FIG. 1 is a flow chart of the working principle of the method for dividing and tensioning the long and short longitudinal prestressed beams of the cantilever construction bridge according to the present invention;
FIG. 2 is a graph showing L- Δ σ scattering and fitting curves of a method for dividing and tensioning control of long and short longitudinal prestressed tendons of a cantilever construction bridge according to embodiment 1 of the present invention;
fig. 3 is a curvature function diagram of an L- Δ σ fitting curve according to an embodiment 1 of the method for controlling division of long and short prestressed tendons of a cantilever construction bridge according to the present invention.
Detailed Description
In order to make the technical means, the inventive features, the achievement objects and the effects of the present invention easy to understand, the technical scheme of the present invention is further described in detail with reference to the accompanying drawings and the detailed description, and the present invention is further described in detail with reference to the embodiments.
The invention discloses a method for controlling division and tensioning of longitudinal prestress long and short beams of a cantilever construction bridge, which comprises the following steps of:
(1) obtaining parameters and parameter values of the bridge longitudinal prestress steel beam for calculating the tension elongation value thereof, and defining delta L1The theoretical elongation value of each steel bundle is obtained; design tension control stress sigmaconVariation. + -. α%, definition Δ L2(α) calculating the elongation value deviation delta l of each steel bundle;
(2) defining delta sigma as tensile stress deviation caused by elongation value error of unit length of the steel bundle, and calculating the delta sigma value of each steel bundle;
(3) drawing a relation graph of the length L of the longitudinal prestressed steel beam and delta sigma, namely an L-delta sigma graph; performing curve fitting on the scattered points of the L-delta sigma graph to obtain a fitting curve regression equation and a correlation coefficient R; the correlation coefficient R should be greater than or equal to 0.98;
(4) determining the critical point of the L-delta sigma fitting curve:calculating a curvature function of the L-delta sigma fitting curve according to the regression equation in the step (3), and solving a maximum curvature point or a stagnation point; taking the maximum curvature point or stationary point of the L-delta sigma fitting curve as the critical point, and recording the coordinate (L) of the critical point0,Δσ0) (ii) a Definition of L0Critical length divided for longitudinal prestress long and short beams;
(5) according to the critical length L of the long and short beam division obtained in the step (4)0Taking the tension control threshold value as a longitudinal prestress tension control threshold value, and determining a tension control criterion as follows:
preferably, in the step (1), the deviation Δ l of the elongation value of the steel bundle is calculated by the formula:
in the formula: Δ L2(α) controlling stress σ for design of tensionconElongation of steel bundle varied by + - α%. DELTA.L1The theoretical elongation value of the steel bundle, α the tensile stress variation rate, the integer is not less than 1 and not more than α and not more than 5, the sigma isconControlling stress for design of tension; k is the influence coefficient of local deviation per meter of the pipeline on friction; x is the length of the pipeline from the tensioning end to the calculated cross section; mu is the friction coefficient between the prestressed tendon and the pipeline wall; theta is the sum of included angles from the tensioning end to the tangent of the pipeline part of the calculated section curve; l is the length of the steel bundle; epIs the modulus of elasticity.
Preferably, in the step (2), the tensile stress deviation Δ σ caused by the elongation value error per unit length of the steel bundle is calculated by the formula:
wherein α is tension control stress variation rate, 1 is equal to or more than α is equal to or less than 5, and sigma is an integerconControlling stress for design of tension; and delta l is the elongation value deviation of the steel bundle.
Preferably, in step (3), the function type of the L- Δ σ fitting curve is generally a negative exponential function.
Preferably, in the step (4), the maximum curvature point or stagnation point of the L-delta sigma fitting curve, namely the critical point, is solved, and the corresponding length L of the steel bundle is obtained0Defined as the critical length of the longitudinal pre-stress long and short beam division.
Preferably, in the step (5), the critical length L for dividing the long and short bundles is determined0As a threshold value of longitudinal prestress tension control, determining a tension control criterion as follows: when L is less than or equal to L0In the process, the principle that tension stress control is used as a main principle and elongation value check is used as an auxiliary criterion is adopted; when L > L0And meanwhile, adopting a principle that tension elongation value control is taken as a main principle and stress check is taken as an auxiliary principle.
Preferably, the elongation value is a single-ended elongation value.
Example 1
A main girder of a prestressed concrete continuous rigid frame bridge with a main span of 150m adopts a single-box single-chamber cross section, and longitudinal prestressed steel bundles of the prestressed concrete continuous rigid frame bridge are divided into four types, namely an early-stage top plate bundle, a web plate bundle, a later-stage top plate bundle and a later-stage bottom plate bundle.
According to the step (1), obtaining the parameter value of the longitudinal prestressed steel beam: l is 13.0 to 148.22m, k is 0.0015, x is L/2 (taking the midspan section), mu is 0.20, the value of theta of each steel strand is calculated, and Ep＝1.95×105MPa，σcon1395 MPa; will sigmaconAnd increasing by 5 percent, and calculating the elongation value deviation delta l of each steel bundle according to the formula (1).
And (3) according to the step (2), calculating the tensile stress deviation delta sigma caused by the elongation value error of the unit length of the steel bundle according to the formula (2).
According to the step (3), drawing an L-delta sigma graph and performing curve fitting on scatter points of the L-delta sigma graph as shown in FIG. 2 to obtain: regression equation y 3474.6x-0.9457(x represents an abscissa parameter L and y represents an ordinate parameter Δ σ); and the correlation coefficient R is 0.999 (more than or equal to 0.98).
According to the step (4), the curvature function of the regression equation is obtained through conversion
Plotting L- Δ σ fittingAs shown in fig. 3, the curve curvature function graph is solved to obtain the maximum curvature point of (63.9,0.01072), and the corresponding L- Δ σ curve critical point is (63.9, 68.1); taking the critical length L divided by the long and short steel bundles0＝63.9m。
According to the step (5), dividing the long steel bundle into the short steel bundle and the short steel bundle into critical lengths L0And (3) determining the longitudinal prestress tension control rule of the bridge as a threshold value of the tension control of the steel bundle, namely 63.9 m: when L is less than or equal to 63.9m, adopting a principle that tensile stress control is used as a main principle and elongation value check is used as an auxiliary principle; when L is larger than 63.9m, the principle that the tension elongation value is mainly controlled and the stress check is assisted is adopted.
Enumeration of analytical results for various examples
The results of the various example analyses are listed below, to be limited by space.
A girder of the following 6 cantilever construction bridges adopts a single-box single-chamber section, and longitudinal prestressed steel bundles of the girder are divided into four types of top plate bundles and web plate bundles in the early stage and top plate bundles and bottom plate bundles in the later stage. Longitudinal prestress steel beam parameter value: l (see bridges), k 0.0015, x L/2 (taking the mid-span section), μ 0.20, θ (calculated for each strand of the bridge), Ep＝1.95×105MPa，σcon1395 MPa. The results of the analysis according to the invention are shown in Table 1.
Table 1 table of analysis results of various examples
According to the analysis results, the main span of the cantilever construction bridge (the main beam adopts a single-box single-chamber section) is in the range of 90-180 m, the length of the longitudinal prestressed steel beam is in the range of 9.8-178.14 m, and the critical length L of the long and short beam division obtained by the method is0Within the range of 63.2-64.6 m, the threshold value of the tension control criterion corresponds to L0Taking 63.2-64.6 m.
The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to be limiting in any way, and any person skilled in the art can make variations or modifications to the above-described embodiments, which are equivalent to the above-described variations, using the teachings of the present invention. Any simple modification, equivalent change and modification of the above embodiments without departing from the technical contents of the present invention or according to the technical spirit of the present invention are within the protection scope of the present invention.
The application range of the invention is as follows:
the invention relates to a longitudinal prestress long and short beam dividing and tensioning control method for a cantilever construction bridge, wherein the bridge is constructed by adopting a segmented cantilever pouring method, and the prestress steel beam material is 1 × 7 (seven strands) and phis15.2mm low-relaxation steel strand with standard tensile strength value fpk1860MPa, modulus of elasticity Ep＝1.95×105MPa。
Claims (7)
1. A longitudinal prestress long and short beam division tensioning control method for a cantilever construction bridge is characterized by comprising the following steps:
(1) obtaining parameters and parameter values of the bridge longitudinal prestress steel beam for calculating the tension elongation value thereof, and defining delta L1The theoretical elongation value of each steel bundle is obtained; design tension control stress sigmaconVariation. + -. α%, definition Δ L2(α) calculating the elongation value deviation delta l of each steel bundle;
(2) defining delta sigma as tensile stress deviation caused by elongation value error of unit length of the steel bundle, and calculating the delta sigma value of each steel bundle;
(3) drawing a relation graph of the length L of the longitudinal prestressed steel beam and delta sigma, namely an L-delta sigma graph; performing curve fitting on the scattered points of the L-delta sigma graph to obtain a fitting curve regression equation and a correlation coefficient R; the correlation coefficient R should be greater than or equal to 0.98;
(4) determining the critical point of the L-delta sigma fitting curve: calculating a curvature function of the L-delta sigma fitting curve according to the regression equation in the step (3), and solving a maximum curvature point or a stagnation point; taking the maximum curvature point or stationary point of the L-delta sigma fitting curve as the critical point, and recording the coordinate (L) of the critical point0,Δσ0) (ii) a Definition of L0Critical length divided for longitudinal prestress long and short beams;
(5) according to the critical length L of the long and short beam division obtained in the step (4)0The value is used as the threshold value of longitudinal prestress tension control,determining a tension control criterion as follows:
2. the cantilever construction bridge longitudinal prestress long and short beam division tensioning control method according to claim 1 is characterized in that:
in the step (1), the calculation formula of the deviation delta l of the elongation value of the steel bundle is as follows:
in the formula: Δ L2(α) controlling stress σ for design of tensionconElongation of steel bundle varied by + - α%. DELTA.L1The theoretical elongation value of the steel bundle, α the tensile stress variation rate, the integer is not less than 1 and not more than α and not more than 5, the sigma isconControlling stress for design of tension; k is the influence coefficient of local deviation per meter of the pipeline on friction; x is the length of the pipeline from the tensioning end to the calculated cross section; mu is the friction coefficient between the prestressed tendon and the pipeline wall; theta is the sum of included angles from the tensioning end to the tangent of the pipeline part of the calculated section curve; l is the length of the steel bundle; epIs the modulus of elasticity.
3. The cantilever construction bridge longitudinal prestress long and short beam division tensioning control method according to claim 1 is characterized in that:
in the step (2), the calculation formula of the tensile stress deviation delta sigma caused by the elongation value error of the unit length of the steel bundle is as follows:
wherein α is tension control stress variation rate, 1 is equal to or more than α is equal to or less than 5, and sigma is an integerconControlling stress for design of tension; and delta l is the elongation value deviation of the steel bundle.
4. The cantilever construction bridge longitudinal prestress long and short beam division tensioning control method according to claim 1 is characterized in that:
in the step (3), the function type of the L- Δ σ fitting curve is generally a negative exponential function.
5. The cantilever construction bridge longitudinal prestress long and short beam division tensioning control method according to claim 1 is characterized in that:
in the step (4), the maximum curvature point or stagnation point of the L-delta sigma fitting curve, namely the critical point, is solved, and the corresponding length L of the steel bundle is obtained0Defined as the critical length of the longitudinal pre-stress long and short beam division.
6. The cantilever construction bridge longitudinal prestress long and short beam division tensioning control method according to claim 1 is characterized in that:
in the step (5), the critical length L of the long and short beams is divided0As a threshold value of longitudinal prestress tension control, determining a tension control criterion as follows: when L is less than or equal to L0In the process, the principle that tension stress control is used as a main principle and elongation value check is used as an auxiliary criterion is adopted; when L > L0And meanwhile, adopting a principle that tension elongation value control is taken as a main principle and stress check is taken as an auxiliary principle.
7. The method for controlling division and tension of the longitudinal prestressed long and short bundles of the cantilever construction bridge according to any one of claims 1 to 3 or 6 is characterized in that:
the elongation value is a single-ended elongation value.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112699512A (en) * | 2021-01-14 | 2021-04-23 | 四川交投建设工程股份有限公司 | Stress midpoint calculation method for multi-line segment asymmetric curve tensile stress |
| CN114329700A (en) * | 2021-12-17 | 2022-04-12 | 湖北工业大学 | Novel calculation method for experimental parameters of prestressed steel beams |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1974931A (en) * | 2006-12-27 | 2007-06-06 | 重庆交通大学 | Box type baseboard prestress concrete variable cross-section box girder bridge and construction method thereof |
| CN101575840A (en) * | 2009-06-02 | 2009-11-11 | 重庆交通大学 | Steel-concrete combined continuous rigid frame bridge construction method for cantilever jointing steel box section |
| US20100088985A1 (en) * | 2008-10-06 | 2010-04-15 | Soletanche Freyssinet | Connection Of Prestressing Sheath Sections Of A Structure Having A Series Of Precast Elements |
| CN105603876A (en) * | 2015-12-24 | 2016-05-25 | 中国铁路总公司 | Dynamic real-time monitoring method for concrete bridge prestressed tendon tensioning force and special prestress construction system |
| CN105781121A (en) * | 2016-03-16 | 2016-07-20 | 浙江大学城市学院 | Determination method for theoretical elongation of bi-directional asymmetric tension prestressing tendon channel |
| CN108647379A (en) * | 2018-03-30 | 2018-10-12 | 中交路桥北方工程有限公司 | Bridge prestress analysis system and method |
-
2020
- 2020-05-12 CN CN202010397948.0A patent/CN111549682A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1974931A (en) * | 2006-12-27 | 2007-06-06 | 重庆交通大学 | Box type baseboard prestress concrete variable cross-section box girder bridge and construction method thereof |
| US20100088985A1 (en) * | 2008-10-06 | 2010-04-15 | Soletanche Freyssinet | Connection Of Prestressing Sheath Sections Of A Structure Having A Series Of Precast Elements |
| CN101575840A (en) * | 2009-06-02 | 2009-11-11 | 重庆交通大学 | Steel-concrete combined continuous rigid frame bridge construction method for cantilever jointing steel box section |
| CN105603876A (en) * | 2015-12-24 | 2016-05-25 | 中国铁路总公司 | Dynamic real-time monitoring method for concrete bridge prestressed tendon tensioning force and special prestress construction system |
| CN105781121A (en) * | 2016-03-16 | 2016-07-20 | 浙江大学城市学院 | Determination method for theoretical elongation of bi-directional asymmetric tension prestressing tendon channel |
| CN108647379A (en) * | 2018-03-30 | 2018-10-12 | 中交路桥北方工程有限公司 | Bridge prestress analysis system and method |
Non-Patent Citations (1)
| Title |
|---|
| 宋泽冈等: "基于参数敏感性分析的预应力筋张拉双控技术", 《中外公路》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112699512A (en) * | 2021-01-14 | 2021-04-23 | 四川交投建设工程股份有限公司 | Stress midpoint calculation method for multi-line segment asymmetric curve tensile stress |
| CN112699512B (en) * | 2021-01-14 | 2023-08-25 | 四川省交通建设集团股份有限公司 | Stress midpoint calculation method for multi-line asymmetric curve tensile stress |
| CN114329700A (en) * | 2021-12-17 | 2022-04-12 | 湖北工业大学 | Novel calculation method for experimental parameters of prestressed steel beams |
| CN114329700B (en) * | 2021-12-17 | 2024-06-07 | 湖北工业大学 | Method for calculating experimental parameters of prestressed steel bundles |
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Application publication date: 20200818 |