CN102535874A - Wind resistance and reinforcement transformation method of high-voltage and superhigh-voltage power transmission line iron tower - Google Patents
Wind resistance and reinforcement transformation method of high-voltage and superhigh-voltage power transmission line iron tower Download PDFInfo
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Abstract
The invention belongs to the technical field of power transmission line equipment, particularly relates to a wind resistance and reinforcement transformation method of a high-voltage and superhigh-voltage power transmission line iron tower. The method comprises the following steps of: increasing a tabula surface at a proper position within the range of a power transmission tower body to improve the rigidity and the stability of the high-voltage and superhigh-voltage power transmission line iron tower, and adopting a method increasing the cross section of a rod piece at a local weak part of a power transmission tower according to different tower shapes to improve local bearing capacity; and in consideration of the safety of the structure of the power transmission tower during site operation, the invention further provides a specific construction method during reinforcement. The method is simple in design and construction, less in steel dosage, and prominent in effect, and can be widely used for the wind resistance and reinforcement transformation of the high-voltage and superhigh-voltage power transmission line iron tower, so that the whole rigidity of the power transmission tower can be improved, and the whole damage caused by the buckling and the instability of a local rod piece can be reduced.
Description
Technical field
The invention belongs to the transmission line equipment technical field, be specifically related to a kind of high pressure and extra high voltage network iron tower wind resistance strengthening reconstruction method.
Background technology
As the important component part of large complicated life line system, the safety issue of transmission system directly influences the production and construction of country and the people's life order.The destruction of transmission line of electricity will cause secondary disasters such as the paralysis of electric power system, also possible initiation fire, cause serious economy loss.Power transmission tower line system has big, the non-linear characteristics such as strong of structure Gao Rou, lead wire and earth wire span, is a kind of wind sensitive structure system.Strong storm is that transmission line of electricity is threatened maximum a kind of natural calamity, and the malicious event of the transmission line of electricity that causes because of strong storm happens occasionally.From eighties of last century nineties, the 500kV transmission line of electricity becomes China's electrical network basic routing line gradually, and along with the growth of line span and tower height, the accumulative total number of times of falling the tower of ultra-high-tension power transmission line is also in rising trend with the number of falling the column foot.During 1989 to 2005, it is 43 bases more that the above power transmission tower generation of China 500kV charming appearance and behaviour is destroyed, and causes serious economic loss.The report that countries such as Japan, Australia have also the time charming appearance and behaviour power transmission tower to destroy.Power transmission tower mainly bears the deadweight and the maximum wind load of lead, ground wire and tower itself, and therefore in the design of linear pattern self-supporting power transmission tower, the wind load control is used.In order to keep integrality performance of the structure and to distribute shearing and antitorque, the tabula face of a determining deviation to be set all in the power transmission tower design.Although the internal force of tabula face is less during designing and calculating, keep the structural integrity effect bigger.Under the cyclone effect, unstability might take place because of bearing excessive internal force in the rod member in the tabula face.Receive with power transmission tower angled wind effect and antitorque calculating in, tabula face performance can obtain the performance.In the aerial power transmission line tower structure designing technique regulation (DLT 5154-2002) of China, the requirement that the tabula face is set proposes with the form that structure requires.The tabula face mainly is located at the section part of body of the tower gradient change, directly receives section part and the cat head and the tower leg top section part of torsion.In constant section of the body of the tower gradient, the spacing of tabula face setting also should not be greater than 4 main material segmentations apart from being not more than 5 times of mean breadths (wide face).Can find out that the electric power pylon ubiquity body of the tower tabula face that is designed according to existing rules is provided with less problem.In this case, the local vibration shape of iron tower structure bottom is very serious, under the dynamic action of wind, if evoke the local vibration shape, probably causes the dynamic buckling of structure to destroy; Static Calculation also shows do not having on the tower section of tabula face, and diagonal brace has very large outer distortion to take place, and this is consistent with the field investigation result that the power transmission tower charming appearance and behaviour is collapsed.To high pressure and extra high voltage network iron tower wind resistance strengthening reconstruction is a problem that urgently will solve at present, the present invention is based on a large amount of investigation of disaster caused by a windstorm destruction, test and computational analysis and has proposed a kind of very effective high pressure and extra high voltage network iron tower wind resistance strengthening reconstruction method.
Summary of the invention
The object of the present invention is to provide a kind of easy construction, cost economic to high pressure and extra high voltage network iron tower wind resistance strengthening reconstruction method.
The strengthening reconstruction method that is used for high pressure and extra high voltage network iron tower wind resistance load that the present invention proposes; Wind resistance to high pressure and extra high voltage network iron tower is assessed; Set up new tabula face 3 according to assessment result in the appropriate location of body of the tower 2 middle and lower parts, to strengthen the integral rigidity of electric power pylon; In addition, to different turriforms, tower head of electric power pylon 4 and the weak rod member in cross-arm 5 places are carried out strengthening reconstruction; Concrete steps are:
(1) wind resistance of high pressure and extra high voltage network iron tower is assessed; Be according to existing structure analysis method; Adopt suitable finite element software, analyze the rigidity situation of electric power pylon, judge according to the result whether the position of tabula face 1 of original code requirement is reasonable; And, find out the position that needs reinforcement according to the requirement for restriction discovery structural weak point of design discipline to displacement structure;
Generally set up new tabula face 3 at the horizontal plane place of the intersection point 7 of four one-level diagonal braces 6 that are positioned at body of the tower 2;, new tabula face 3 self must be a geometry unchanged body, transmits horizontal shear to reach whole, rationalizes the effect of distributing shearing; The design of geometry unchanged body can be with reference to existing rules; Its form is (should specify which kind of body, accompanying drawing can not say something) shown in accompanying drawing 3, and standardized designs is carried out according to the cross section of existing rod member in tabula surface member cross section.Because new tabula face 3 has rigidity in the bigger face, can avoid one-level diagonal brace node 7 that big deformity out of plane takes place integral body of one-level diagonal brace 6 formation constrained each other of 2 four faces of body of the tower; Meanwhile, one-level diagonal brace 6 direction outside the face of new tabula face 3 also plays the effect of diagonal brace tabula face, avoids the tabula face that distortion and vertical motion outside the excessive face take place outside face.Between new tabula face 3 and the one-level diagonal brace 6 two each other near plane orthogonal in constraint each other, diagonal brace has each other formed the integral body of a common holding capacity; Before body of the tower 2 is set up new tabula face 3, need to remove original secondary diagonal brace 8, this will make the intersection point 7 of one-level diagonal brace and the more former design of length of the tabula face main member 12 between the body of the tower master material 11 become big, and unstability takes place easily.Therefore need set up some new secondary diagonal braces 9; These secondary diagonal braces are different with the direction of original secondary diagonal brace 8; New secondary diagonal brace 9 one end diagonal braces are on tabula face side quartile 10, and an other end is connected with secondary diagonal brace 9 or body of the tower master material 11, shown in accompanying drawing 2 and 4.
(2) for the tower head of directly bearing the lead wire and earth wire load 4 and cross-arm 5, it is less with the bar cross section on the cross-arm 5 to be positioned at tower head 4, and the existing diagonal brace more than 14 of member bottom surface is unidirectional, is easy to take place strength failure, the generation large deformation.Therefore need increase new diagonal brace 15 to rod member increasing section size or on the existing diagonal brace 14 on tower head and the cross-arm; Said new diagonal brace 15 is bidirectional crossed arrangement with existing diagonal brace 14; In the installation process, new diagonal brace and original member intersection point place need beat bolt hole 16 and fix with bolt.
Find through structural analysis and test contrast: after suitably increasing new tabula face 3, the overall performance of power transmission tower structure can be greatly improved, and the face outer displacement of this tower section diagonal brace can significantly be reduced, and has reduced the possibility of the outer unstability of face.The existence of tabula face makes the electric power pylon wind resistance be significantly strengthened.
Two reinforcement measures that the present invention proposes, full-scope safeguards integral rigidity, shear behavior and the local strength of high pressure and extra high voltage network iron tower, make electric power pylon can bear the dynamic load that strong storm causes and be unlikely to lose bearing capacity.Thinking of the present invention is simply clear, easy construction, and effect is remarkable, and cost is comparatively economical, and the wind resistance that can be widely used in high pressure and extra high voltage network iron tower is transformed in the stabilization works.
Description of drawings
The overall structure figure of Fig. 1 electric power pylon.
The unguyed pre-structure figure of Fig. 2 body of the tower hypomere.
The structure chart of Fig. 3 tabula face.Wherein, figure (a) with (b) be the inner tabula face that adds counterbracing, scheme (c) and (d) add the tabula face of little diagonal brace for the edge.
Fig. 4 removes original secondary diagonal brace and sets up the body of the tower hypomere sketch map of tabula face main member.
Fig. 5 sets up body of the tower hypomere sketch map behind the new secondary diagonal brace.
Cross-arm schematic bottom view before Fig. 6 transforms.
Fig. 7 increases the cross-arm schematic bottom view after the counterbracing.
Label among the figure: 1 is the tabula face of code requirement, and 2 is body of the tower, and 3 is new tabula face, and 4 is tower head; 5 is cross-arm, and 6 is the one-level diagonal brace of body of the tower, and 7 is the intersection point of one-level diagonal brace, and 8 is original secondary diagonal brace; 9 is new secondary diagonal brace, and 10 is tabula face side quartile, and 11 is body of the tower master material, and 12 is the main member of tabula face; 13 is the secondary member of tabula face, and 14 is the existing diagonal brace at tower head and cross-arm position, and 15 are newly-increased diagonal brace, and 16 is the new bolt hole in crosspoint.
The specific embodiment
Below in conjunction with accompanying drawing and practical implementation example the present invention is explained further details.
Embodiment 1: for the high pressure and the extra high voltage network iron tower that suffer the strong storm area easily, at first confirm to set up the position of tabula face through the certain structure analytical method.For the body of the tower substructure shown in accompanying drawing 2, calculating shows that two body of the tower gradients between the tabula face are consistent, and is fewer by the tabula face number that rules are provided with, thereby cause the body of the tower lower semisection to lack the outer diagonal brace of effective face, is a weak spot.Set up two new tabula faces 3 through horizontal plane place, can effectively suppress the local vibration shape and occur too early, and obviously reduce the deformity out of plane of one-level diagonal brace at one-level diagonal brace intersection point 7.These two tabula face structures are chosen like the form in the accompanying drawing 3; Because each rod member is stressed all less in the tabula face; Mainly be for the reinforcement globality; Therefore the selection of diagonal angle steel dimensions need not calculated, only need to satisfy structure requires and design discipline in for the control requirement of rod member slenderness ratio.
According to the drawing of high pressure and extra high voltage network iron tower, obtain the size of body of the tower horizontal section, one-level diagonal brace intersection point 7 place, choose the form of rational tabula face.Simultaneously, consider the construction requirement of tabula face, original secondary diagonal brace 8 need be removed; Tower after the dismounting can find out and remove after original secondary diagonal brace that the length of the main member 12 of new tabula face is long shown in accompanying drawing 4; Easy unstability; Therefore needing increases some new secondary diagonal braces 9 in the position shown in accompanying drawing 5, and these rod member one ends are fixed on the quartile 10 of tabula face side, and the other end is connected with one-level diagonal brace or main material; Thereby make new tabula face and one-level diagonal brace synergy, and reduce the calculated length of all kinds of rod members.The cross section selection principle of new secondary diagonal brace is consistent with the tabula face of newly establishing, and by slenderness ratio control, only needs to satisfy the structure requirement.After choosing the sectional dimension of tabula face form of structure and all newly-increased members, can transfer to processing factory's blanking and make.The monolateral connection of bolt is all adopted in all connections, accomplishes fluently screw in processing factory, only need carry out assembly unit at the construction field (site), is easy to site operation, and is simple.
Sequence of construction need be strictly observed during the site assembly of tabula face, and certain meteorological condition need be satisfied.Owing to remove original secondary diagonal brace the calculated length of main material and one-level diagonal brace is increased, the flexing load reduces accordingly, so this work must carry out under little wind (force 3 wind) situation, and can only to four faces of body of the tower one by one face operate; After removing original secondary diagonal brace, begin to install the main member of tabula face; New secondary diagonal brace is installed afterwards, and the link position of new secondary diagonal brace and other members can be used and remove the left screw of original diagonal brace; After the member transformation of treating four faces of body of the tower installs, carry out the installation of secondary member in the tabula face again.All bolted construction qualities need meet the regulation in the existing delivery receiving acceptance rules.When body of the tower has the position of intersecting point of two or more one-level diagonal braces need set up the tabula face, must construct successively from top to bottom, can not construct simultaneously to two positions.
The cross-arm bottom surface of this tower has only unidirectional diagonal brace, makes that the pressurized main member slenderness ratio of both sides is excessive, and therefore increasing diagonal brace 15 makes it to transform as bidirectional crossed diagonal brace, and new diagonal brace cross section should be consistent with existing unidirectional diagonal brace, and when produce in factory, accomplish fluently bolt hole.At the scene erection sequence should for, from the inboard beginning of cross-arm, accomplish fluently the bolt hole that is used for fixing a diagonal brace earlier, this diagonal brace is installed then, carry out the punching and the installation of next diagonal brace again, carry out toward the cross-arm outboard end successively.
Claims (1)
1. high pressure and extra high voltage network iron tower wind resistance strengthening reconstruction method; It is characterized in that the wind resistance of high pressure and extra high voltage network iron tower is assessed; Set up new tabula face (3) according to assessment result in the appropriate location of body of the tower (2) middle and lower part, to strengthen the integral rigidity of electric power pylon; To different turriforms, the tower head (4) of electric power pylon and cross-arm (5) are located weak rod member carry out strengthening reconstruction; Concrete steps are:
(1) wind resistance of high pressure and extra high voltage network iron tower is assessed; Be according to existing structure analysis method; Adopt suitable finite element software, analyze the rigidity situation of electric power pylon, judge according to the result whether the position of tabula face 1 of original code requirement is reasonable; And, find out the position that needs reinforcement according to the requirement for restriction discovery structural weak point of design discipline to displacement structure;
Horizontal plane place at the intersection point (7) of four the one-level diagonal braces (6) that are positioned at body of the tower (2) sets up new tabula face (3); Because new tabula face (3) has rigidity in the bigger face; With integral body of one-level diagonal brace (6) formation constrained each other of (2) four faces of body of the tower, avoid one-level diagonal brace node (7) that big deformity out of plane takes place; Simultaneously, one-level diagonal brace (6) direction outside the face of new tabula face (3) plays the effect of diagonal brace tabula face, avoids tabula face (1) that distortion and vertical motion outside the excessive face take place outside face; Between new tabula face (3) and the one-level diagonal brace (6) two each other near plane orthogonal in constraint each other, diagonal brace each other, the integral body of a common holding capacity of formation; Set up new tabula face (3) before at body of the tower (2); Need to remove original secondary diagonal brace (8); Set up new secondary diagonal brace (9); New secondary diagonal brace (9) is different with the direction of original secondary diagonal brace (8), and new secondary diagonal brace (9) one end diagonal braces are on tabula face side quartile (10), and an other end is connected with secondary diagonal brace (9) or body of the tower master material (11); Avoided unstable phenomenon taking place because the more former design of the length of the intersection point (7) of one-level diagonal brace and the tabula face main member (12) between the body of the tower master material (11) becomes big;
(2) for the tower head of directly bearing the lead wire and earth wire load (4) and cross-arm (5); The bar cross section that is positioned on tower head (4) and the cross-arm (5) is less; And mostly the existing diagonal brace (14) of member bottom surface is unidirectional; Through rod member increasing section size or the existing diagonal brace (14) on tower head and cross-arm are gone up the new diagonal brace (15) of increase; Said new diagonal brace (15) is bidirectional crossed arrangement with existing diagonal brace (14), and in the installation process, new diagonal brace (15) is fixed through bolt hole (16) and bolt with existing diagonal brace (14) intersection point place.
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Cited By (10)
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CN102767293A (en) * | 2012-08-07 | 2012-11-07 | 广东电网公司佛山供电局 | Strengthening method for power transmission tower on hazardous area of landslide |
CN104831981A (en) * | 2015-04-30 | 2015-08-12 | 中国电力科学研究院 | Power transmission tower |
CN104989152A (en) * | 2015-06-09 | 2015-10-21 | 广东电网有限责任公司电力科学研究院 | Crisscross overhead power transmission tower |
CN105003116A (en) * | 2015-06-09 | 2015-10-28 | 广东电网有限责任公司电力科学研究院 | Overhead power transmission tower with high integral wind-resistant performance |
CN105389436A (en) * | 2015-11-16 | 2016-03-09 | 国网山东省电力公司电力科学研究院 | Charged reinforcing and strengthening method for power transmission tower |
CN106920021A (en) * | 2015-12-25 | 2017-07-04 | 中国电力科学研究院 | A kind of iron tower of power transmission line integrality appraisal procedure |
CN109209001A (en) * | 2018-10-31 | 2019-01-15 | 国网四川省电力公司绵阳供电公司 | A kind of steel tower column foot bracing means and reinforcement means |
CN113266192A (en) * | 2021-04-13 | 2021-08-17 | 北方工业大学 | Bracing wire reinforcing method for tower body of self-supporting power transmission tower |
CN114016803A (en) * | 2021-11-12 | 2022-02-08 | 贵州电网有限责任公司 | Reinforcing method for improving net section strength of outer-veneer-type old line iron tower |
CN114033240A (en) * | 2021-12-07 | 2022-02-11 | 中国南方电网有限责任公司超高压输电公司广州局 | Cross arm for +/-800 kV direct-current emergency repair tower |
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Cited By (14)
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CN102767293A (en) * | 2012-08-07 | 2012-11-07 | 广东电网公司佛山供电局 | Strengthening method for power transmission tower on hazardous area of landslide |
CN104831981A (en) * | 2015-04-30 | 2015-08-12 | 中国电力科学研究院 | Power transmission tower |
CN104989152A (en) * | 2015-06-09 | 2015-10-21 | 广东电网有限责任公司电力科学研究院 | Crisscross overhead power transmission tower |
CN105003116A (en) * | 2015-06-09 | 2015-10-28 | 广东电网有限责任公司电力科学研究院 | Overhead power transmission tower with high integral wind-resistant performance |
CN105389436B (en) * | 2015-11-16 | 2018-08-17 | 国网山东省电力公司电力科学研究院 | A kind of power transmission tower electrification reinforcement and strengthening method |
CN105389436A (en) * | 2015-11-16 | 2016-03-09 | 国网山东省电力公司电力科学研究院 | Charged reinforcing and strengthening method for power transmission tower |
CN106920021A (en) * | 2015-12-25 | 2017-07-04 | 中国电力科学研究院 | A kind of iron tower of power transmission line integrality appraisal procedure |
CN106920021B (en) * | 2015-12-25 | 2020-08-18 | 中国电力科学研究院 | Method for evaluating overall state of power transmission line iron tower |
CN109209001A (en) * | 2018-10-31 | 2019-01-15 | 国网四川省电力公司绵阳供电公司 | A kind of steel tower column foot bracing means and reinforcement means |
CN109209001B (en) * | 2018-10-31 | 2020-02-18 | 国网四川省电力公司绵阳供电公司 | Iron tower foot reinforcing device and reinforcing method |
CN113266192A (en) * | 2021-04-13 | 2021-08-17 | 北方工业大学 | Bracing wire reinforcing method for tower body of self-supporting power transmission tower |
CN114016803A (en) * | 2021-11-12 | 2022-02-08 | 贵州电网有限责任公司 | Reinforcing method for improving net section strength of outer-veneer-type old line iron tower |
CN114016803B (en) * | 2021-11-12 | 2023-07-18 | 贵州电网有限责任公司 | Reinforcing method for improving net section strength of externally-attached plate type old line iron tower |
CN114033240A (en) * | 2021-12-07 | 2022-02-11 | 中国南方电网有限责任公司超高压输电公司广州局 | Cross arm for +/-800 kV direct-current emergency repair tower |
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Application publication date: 20120704 |