A steel truss main truss hoisting method

Abstract

The present application provides a kind of steel truss main truss hoisting method, including the main truss design of each section of steel truss is divided into lower half truss piece and upper half truss piece;After the lower half truss piece and upper half truss piece are manufactured in factory, horizontal transport to construction site;Hoisting is carried out using a gantry crane on site, a main hook and a secondary hook are arranged on the gantry crane;When hoisting, the lower half truss piece and upper half truss piece are respectively turned over 90° from horizontal state to vertical state using the main hook and secondary hook of the gantry crane, and then hoisted to the support;The lower half truss piece and upper half truss piece are connected into a whole truss piece on the support through high-strength bolts and other steps.The present application can reduce the number of rod members on-site hoisting and connection, improve hoisting efficiency, and save mechanical and labor costs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel truss construction, in particular to a steel truss main truss hoisting method. BACKGROUND

[0002] The steel truss is composed of several segments in the bridge direction, and each segment has basically the same structure, which is composed of a main truss, a deck, and a truss interconnection system. The main truss is the main load-bearing component of the steel truss, which is composed of top chord, bottom chord and web member. The main truss is processed and manufactured in a professional factory and then transported to the construction site for installation. Depending on the transportation conditions and the hoisting conditions at the construction site, the main truss of the steel beam has different rod segmentation schemes in design, manufacturing, transportation and hoisting.

[0003] In the case where the whole truss piece transportation and hoisting conditions are not met, the current construction scheme is to split the main truss into multiple rods, and then manufacture, transport and hoist the scattered parts. The rods are connected into a whole through bolting or riveting at the construction site. This scattered hoisting method has high bolt connections at the main truss nodes, which is not as good as the whole node quality, affects the appearance quality, and the construction time of hoisting and connecting the components at the construction site is long. SUMMARY

[0004] In view of the above prior art, the present application provides a steel truss main truss hoisting method.

[0005] The steel truss main truss hoisting method provided by the present application comprises the following steps:

[0006] S1, the main truss of each segment of the steel truss is designed to be divided into a lower half truss piece and an upper half truss piece, and a plurality of lifting lugs are installed on the lower half truss piece and the upper half truss piece according to the position of the center of gravity;

[0007] S2, after the lower half truss piece and the upper half truss piece are manufactured in the factory, they are horizontally transported to the construction site;

[0008] S3, a gantry crane is used for hoisting at the construction site, and a main hook and a secondary hook are arranged on the gantry crane; during hoisting, the main hook and the secondary hook of the gantry crane are used to cooperate to turn the lower half truss piece and the upper half truss piece from a horizontal state to a vertical state by 90°, and then hoist them onto a support;

[0009] S4, the lower half truss piece and the upper half truss piece are connected into a whole truss piece through high-strength bolts on the support.

[0010] Preferably, in S1, the main truss is divided into two irregular lower half truss pieces and upper half truss pieces along the center line in the height direction.

[0011] Preferably, in S1, the position of the center of gravity is calculated by software modeling, and six lifting lugs are installed on the lower half truss piece and the upper half truss piece, respectively.

[0012] Preferably, in the horizontal state, the first lifting lug and the second lifting lug are oppositely arranged and uniformly distributed above the two sides of the first gravity center, and the third lifting lug and the fourth lifting lug are oppositely arranged and uniformly distributed below the two sides of the first gravity center.

[0013] Preferably, the interval of the first lifting lug and the second lifting lug is greater than the interval of the third lifting lug and the fourth lifting lug.

[0014] Preferably, in the horizontal state, the seventh lifting lug, the eighth lifting lug, the ninth lifting lug and the tenth lifting lug are uniformly arranged on the upper end surface of the upper half truss and located on the two sides of the second gravity center, and the eleventh lifting lug and the twelfth lifting lug are oppositely arranged and uniformly distributed below the two sides of the second gravity center.

[0015] Preferably, the main hook and the auxiliary hook of the gantry crane are arranged in the shape of "mountain".

[0016] Compared with the prior art, the beneficial effects of the present application are as follows: in the case that the whole truss cannot be transported and hoisted, the present application provides a steel truss main truss hoisting method, which adopts irregular half trusses for hoisting. Compared with the scattered piece hoisting method, the connection between the web member and the upper and lower chord members is changed from the high bolt connection on site to the integral structure welded in the factory, which improves the steel beam quality and makes the appearance of the truss more simple and beautiful. At the same time, the number of rod pieces hoisted and connected on site is reduced, the hoisting efficiency is improved, and the mechanical and labor costs are saved. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 FIG. 1 is a schematic view of the right side of the lower half truss in the embodiment of the present application.

[0018] Figure 2 FIG. 2 is a schematic view of the left side of the lower half truss in the embodiment of the present application.

[0019] Figure 3 FIG. 3 is a schematic view of the right side of the upper half truss in the embodiment of the present application.

[0020] Figure 4 FIG. 4 is a schematic view of the left side of the upper half truss in the embodiment of the present application.

[0021] Figure 5 FIG. 5 is a schematic view of the structure of the gantry crane in the embodiment of the present application.

[0022] In the diagram: 1. Lower half of the truss; 2. Upper half of the truss; 3. First center of gravity; 4. Second center of gravity; 5. First lifting lug; 6. Second lifting lug; 7. Third lifting lug; 8. Fourth lifting lug; 9. Fifth lifting lug; 10. Sixth lifting lug; 11. Seventh lifting lug; 12. Eighth lifting lug; 13. Ninth lifting lug; 14. Tenth lifting lug; 15. Eleventh lifting lug; 16. Twelfth lifting lug; 17. Main hook; 18. Secondary hook. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0024] like Figures 1-5 As shown, the present invention provides a method for hoisting a main steel truss, comprising the following steps:

[0025] S1. Divide the main truss of each segment of the steel truss beam into two irregular lower half truss segments 1 and upper half truss segments 2 along the center line from the height direction. Calculate the position of the first center of gravity 3 on the lower half truss segment 1 and the position of the second center of gravity 4 on the upper half truss segment 2 by software modeling. Install six lifting lugs on each of the lower half truss segment 1 and the upper half truss segment 2 according to the positions of the two centers of gravity.

[0026] In the horizontal state, the reference Figure 1 A first lifting lug 5, a second lifting lug 6, a third lifting lug 7, and a fourth lifting lug 8 are provided on the right side of the lower half-truss 1. The first lifting lug 5 and the second lifting lug 6 are arranged opposite each other and evenly distributed on both sides above the first center of gravity 3. The third lifting lug 7 and the fourth lifting lug 8 are arranged opposite each other and evenly distributed on both sides below the first center of gravity 3. (Refer to...) Figure 2 A fifth lifting lug 9 and a sixth lifting lug 10 are provided on the left side of the lower half-truss 1. The fifth lifting lug 9 and the sixth lifting lug 10 are arranged opposite each other and are evenly distributed on both sides above the first center of gravity 3. The distance between the first lifting lug 5 and the second lifting lug 6 is greater than the distance between the third lifting lug 7 and the fourth lifting lug 8.

[0027] In a horizontal state, refer to Figure 3 , 4 The seventh lifting lug 11, the eighth lifting lug 12, the ninth lifting lug 13 and the tenth lifting lug 14 are evenly arranged on the upper end face of the upper half truss 2 and on both sides of the second center of gravity 4; the eleventh lifting lug 15 and the twelfth lifting lug 16 are arranged on the right side of the upper half truss 2. The eleventh lifting lug 15 and the twelfth lifting lug 16 are arranged opposite each other and evenly distributed on both sides below the second center of gravity 4.

[0028] In this way, the position of each lifting lug can ensure that the truss is lifted smoothly and rotated easily, while also meeting the stress requirements.

[0029] S2, after the lower half of the beam 1 and the upper half of the beam 2 are completed in the factory, they are transported to the construction site by ship.

[0030] S3, referring to Figure 5 , the gantry crane is used for hoisting, the main hook 17 and the auxiliary hook 18 are arranged on the gantry crane, and the main hook 17 and the auxiliary hook 18 are arranged in the shape of “shan” character; during hoisting, the main hook 17 and the auxiliary hook 18 are used in cooperation to respectively turn the lower half of the beam 1 and the upper half of the beam 2 by 90° from the horizontal state to the vertical state, and then hoist them to the support, and each main truss is hoisted with the lower half of the beam 1 first, and then hoisted with the upper half of the beam 2.

[0031] S4, the lower half of the beam 1 and the upper half of the beam 2 are connected into a whole beam on the support through high-strength bolts.

[0032] Taking a practical bridge construction project as an example, the standard length of the steel truss beam main truss of the project is 20 meters, the truss height is 12 meters, each main truss is divided into the lower half of the beam 1 and the upper half of the beam 2 along the height center line, and the maximum single hoisting weight is 114 tons.

[0033] The specific hoisting steps of the lower half of the beam 1 include the following steps: a, the main hook 17 of the gantry crane is hung with four steel wires to connect the first lifting lug 5, the second lifting lug 6, the third lifting lug 7 and the fourth lifting lug 8, the lower half of the beam 1 is horizontally lifted and placed on the sleeper; b, the steel wires connected with the third lifting lug 7 and the fourth lifting lug 8 are replaced with the fifth lifting lug 9 and the sixth lifting lug 10, and are still hung on the main hook 17; c, the steel wires connected with the first lifting lug 5 and the second lifting lug 6 are taken off from the main hook 17 and hung on the auxiliary hook 18; d, the main hook 17 and the auxiliary hook 18 are synchronously lifted and transversely moved to the direction in which the lower half of the beam 1 is to be turned, so that the lower chord bottom edge of the lower half of the beam 1 is used as the shaft to rotate on the sleeper until the lower half of the beam 1 is turned into the vertical state; e, the two steel wires hung on the auxiliary hook 18 are transferred and hung on the main hook 17 again, the main hook 17 is lifted to vertically lift the lower half of the beam 1 and place it on the assembling support.

[0034] The specific hoisting steps of the upper half of the beam 2 include the following steps: a, the main hook 17 of the gantry crane is hung with four steel wires to connect the seventh lifting lug 11, the eighth lifting lug 12, the ninth lifting lug 13 and the tenth lifting lug 14, the auxiliary hook 18 is hung with two steel wires to connect the eleventh lifting lug 15 and the twelfth lifting lug 16, the main hook 17 and the auxiliary hook 18 are simultaneously lifted to horizontally lift the upper half of the beam 2 to the air, and the lifting is stopped when the height of the upper half of the beam 2 from the ground exceeds the height of the upper half of the beam 2 itself; b, the main hook 17 continues to lift, while the auxiliary hook 18 slowly descends, the upper half of the beam 2 is slowly turned to the vertical state, and finally only the main hook 17 is stressed; c, the main hook 17 lifts the upper half of the beam 2 to the support and connects it with the lower half of the beam 1.

[0035] The above merely illustrates the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure made according to the content of the present application specification and drawings, directly or indirectly applied in other related technical fields, are also within the patent protection scope of the present application.

Claims

1. A method for hoisting a main truss of a steel truss beam, characterized in that, It includes the following steps: S1. Divide the main truss of each segment of the steel truss girder into a lower half truss panel and an upper half truss panel, and install several lifting lugs on the lower half truss panel and the upper half truss panel respectively according to the position of the center of gravity; divide the main truss evenly along the center line in the height direction to form two irregular lower half truss panels and upper half truss panels; the position of the center of gravity is calculated by software modeling, and six lifting lugs are installed on the lower half truss panel and the upper half truss panel respectively; In the horizontal state, set the first lifting lug, the second lifting lug, the third lifting lug and the fourth lifting lug on the right side surface of the lower half truss panel. The first lifting lug and the second lifting lug are arranged oppositely and evenly distributed above both sides of the first center of gravity. The third lifting lug and the fourth lifting lug are arranged oppositely and evenly distributed below both sides of the first center of gravity; set the fifth lifting lug and the sixth lifting lug on the left side surface of the lower half truss panel. The fifth lifting lug and the sixth lifting lug are arranged oppositely and evenly distributed above both sides of the first center of gravity; S2. After the lower half truss panel and the upper half truss panel are manufactured in the factory, transport them horizontally to the construction site; S3. Use a gantry crane for hoisting on site. The gantry crane is equipped with a main hook and a deputy hook; during hoisting, cooperate with the main hook and the deputy hook of the gantry crane to turn the lower half truss panel and the upper half truss panel from the horizontal state to the vertical state by 90° respectively, and then hoist them onto the support; S4. Connect the lower half truss panel and the upper half truss panel into a whole truss panel with high-strength bolts on the support.

2. The method for hoisting the main truss of a steel truss as described in claim 1, characterized in that, The distance between the first lifting lug and the second lifting lug is greater than the distance between the third lifting lug and the fourth lifting lug.

3. The method for hoisting the main truss of a steel truss as described in claim 1, characterized in that, In the horizontal state, evenly set the seventh lifting lug, the eighth lifting lug, the ninth lifting lug and the tenth lifting lug on the upper end surface of the upper half truss panel and on both sides of the second center of gravity; set the eleventh lifting lug and the twelfth lifting lug on the right side surface of the upper half truss panel. The eleventh lifting lug and the twelfth lifting lug are arranged oppositely and evenly distributed below both sides of the second center of gravity.

4. The method for hoisting the main truss of a steel truss as described in claim 1, characterized in that, Both the main hook and the deputy hook of the gantry crane are set in the shape of "mountain".

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