阅读说明：本技术 一种宽桥面变桁片式悬索桥钢桁梁及桁片的设计方法 (Wide bridge deck variable truss sheet type suspension bridge steel truss girder and truss sheet design method ) 是由 邹敏勇 郑亚鹏 刘科峰 万田保 杨光武 程子涵 汪威 刘奇顺 于 2021-08-04 设计创作，主要内容包括：本申请涉及一种宽桥面变桁片式悬索桥钢桁梁,涉及桥梁施工技术领域,其包括中跨区和两个边跨区,中跨区包括沿横桥向间隔设置的两个主桁片,以及横设于两个主桁片之间的主横梁；两个边跨区沿纵桥向分设于中跨区的两端,边跨区包括两个第一边桁片、第二边桁片和两个边横梁,两个第一边桁片沿横桥向间隔设置,并分别沿纵桥向延伸至与两个主桁片连接；第二边桁片位于两个第一边桁片之间,并沿纵桥向延伸至与主横梁连接；两个边横梁分别横设于第二边桁片与两个第一边桁片之间,并沿纵桥向延伸至与主横梁连接。本申请可以大大降低中跨区的主桁片的用钢量,以降低全桥用钢量；减小了边跨区的边横梁的跨度,降低了边横梁横向变形,有利于轨道的平顺性。(The application relates to a steel truss girder of a wide bridge deck variable truss type suspension bridge, which relates to the technical field of bridge construction and comprises a midspan area and two side span areas, wherein the midspan area comprises two main truss pieces arranged at intervals along the transverse bridge direction and a main cross beam transversely arranged between the two main truss pieces; the two side span areas are respectively arranged at two ends of the middle span area along the longitudinal bridge direction, each side span area comprises two first side truss sheets, a second side truss sheet and two side cross beams, and the two first side truss sheets are arranged at intervals along the transverse bridge direction and respectively extend to be connected with the two main truss sheets along the longitudinal bridge direction; the second edge truss sheet is positioned between the two first edge truss sheets and extends to be connected with the main cross beam along the longitudinal bridge direction; the two edge cross beams are respectively transversely arranged between the second edge truss sheet and the two first edge truss sheets and extend to be connected with the main cross beam along the longitudinal bridge direction. The steel consumption of the main truss pieces in the midspan area can be greatly reduced, so that the steel consumption of the full bridge is reduced; the span of the edge beam in the edge cross area is reduced, the transverse deformation of the edge beam is reduced, and the smoothness of the track is facilitated.)

1. The utility model provides a wide bridge face becomes purlin piece formula suspension bridge steel longeron which characterized in that, it includes:

the midspan area (1) comprises two main truss sheets (10) arranged at intervals along the transverse bridge direction, and a main cross beam (11) transversely arranged between the two main truss sheets (10);

two side span regions (2), two side span regions (2) are arranged at two ends of the middle span region (1) along the longitudinal bridge direction, and the side span regions comprise:

-two first side web pieces (20), the two first side web pieces (20) being spaced apart in the transverse direction and extending in the longitudinal direction to connect to the two main web pieces (10), respectively;

-a second side web (21) located between two of said first side webs (20) and extending in a longitudinal bridging direction to connect with said main beam (11);

-two side beams (22), the two side beams (22) being respectively arranged transversely between the second side beam piece (21) and the two first side beam pieces (20) and extending in a longitudinal bridge direction to be connected with the main beam (11).

2. The wide deck truss type suspension bridge steel truss of claim 1 wherein said second side truss sheet (21) is located intermediate of two of said first side truss sheets (20).

3. The wide deck variable truss suspension bridge steel truss of claim 1 wherein the main truss sheet (10), the first side truss sheet (20) and the second side truss sheet (21) each include: the steel truss girder comprises an upper chord (100) and a lower chord (101) which are arranged at intervals in the height direction of the steel truss girder, and a plurality of web members (102) connected between the upper chord (100) and the lower chord (101).

4. The wide deck variable truss sheet suspension bridge steel truss of claim 3 wherein:

the main cross beam (11) comprises a first main cross beam (110) and a second main cross beam (111), the first main cross beam (110) is arranged between upper chords (100) of the two main truss sheets (10), and the second main cross beam (111) is arranged between lower chords (101) of the two main truss sheets (10);

the side beam (22) comprises a first side beam (220) and a second side beam (221), the first side beam (220) is arranged between the first side truss piece (20) and the upper chord (100) of the second side truss piece (21), and the second side beam (221) is arranged between the first side truss piece (20) and the lower chord (101) of the second side truss piece (21).

5. The method for designing the truss of the wide deck variable truss type suspension bridge steel truss girder according to claim 1, comprising the steps of:

reducing the initial width W of the bar section of the main girder (10)_{Master and slave}And an initial height H_{Master and slave}To obtain the width to be optimizedAnd height

Will be provided withAndan initial width W of a bar section as the first side girder piece (20)_{Edge 1}And an initial height H_{Edge 1}(ii) a And will beAn initial width W of a bar section as the second side girder piece (21)_{Edge 2}；

According to the internal force of the bars of the first (20) and second (21) edge webs_{Edge 1}，H_{Edge 1}，W_{Edge 2}And the initial height H of the bar section of the second edge beam piece (21)_{Edge 2}Obtaining an initial thickness D of the bar section of the first side truss piece (20) and the second side truss piece (21)_Edge；

Judgment of D_EdgeWhether a threshold value is exceeded;

if greater than the threshold, increaseAndrepeating the above steps until D_EdgeSubstantially equal to the threshold;

if less than the threshold, continue to decreaseAndrepeating the above steps until D_EdgeSubstantially equal to said threshold value.

6. The method for designing the truss sheet of the wide deck variable truss sheet type suspension bridge steel truss girder according to claim 5, wherein the main truss sheet (10), the first side truss sheet (20) and the second side truss sheet (21) each comprise: the steel truss girder comprises an upper chord (100) and a lower chord (101) which are arranged at intervals in the height direction of the steel truss girder, and a plurality of web members (102) connected between the upper chord (100) and the lower chord (101).

7. The method for designing the trusses of the steel truss girder of the wide-deck variable-truss type suspension bridge according to claim 6, wherein the method specifically comprises the following steps:

upper chords (100) and (100) respectively reducing the main truss web (10)Initial width W of cross section of lower chord (101)_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}And respectively as the width to be optimized of the upper chord (100) and lower chord (101) sections of the main truss sheet (10)Andand height to be optimizedAnd

will be provided withAndinitial widths W of the cross sections of the upper chord (100) and the lower chord (101) of the first side truss piece (20)_{On the edge 1}And W_{Under the edge 1}And the initial width W of the sections of the upper chord (100) and the lower chord (101) of the second side truss sheet (21)_{On the edge 2}And W_{Under the edge 2}(ii) a And will beAndinitial height H of the cross section of the upper chord (100) and the lower chord (101) of the first side truss sheet (20)_{On the edge 1}And H_{Under the edge 1}；

According to the internal forces of the upper chord (100) and the lower chord (101) of the first side truss sheet (20), and W_{On the edge 1}，W_{Under the edge 1}，H_{On the edge 1}And H_{Under the edge 1}Obtaining the initial thickness D of the sections of the upper chord (100) and the lower chord (101) of the first side truss sheet (20)_{On the edge 1}And D_{Under the edge 1}；

According to the internal force of the upper chord (100) and the lower chord (101) of the second side truss sheet (21), W_{On the edge 2}And W_{Under the edge 2}And the initial height H of the upper chord (100) and the lower chord (101) of the second edge truss sheet (21)_{On the edge 2}And H_{Under the edge 2}Obtaining the initial thickness D of the sections of the upper chord (100) and the lower chord (101) of the second side truss sheet (21)_{On the edge 2}And D_{Under the edge 2}；

Judgment of D_{On the edge 1}And D_{Under the edge 1}And D_{On the edge 2}And D_{Under the edge 2}Whether a threshold value is exceeded;

if D is_{On the edge 1}Or D_{On the edge 2}Beyond the threshold, increaseAndrepeating the above steps until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{Under the edge 1}Or D_{Under the edge 2}Beyond the threshold, increaseAndrepeating the above steps until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to the threshold;

if D is_{On the edge 1}Or D_{On the edge 2}Less than the threshold, continue to decreaseAndrepeating the above steps until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{Under the edge 1}Or D_{Under the edge 2}Less than the threshold, continue to decreaseAndrepeating the above steps until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to said threshold value.

8. The method of claim 5, further comprising obtaining W_{Master and slave}And H_{Master and slave}The method comprises the following specific steps:

establishing an initial model of the steel truss girder, wherein an edge span area (2) in the initial model comprises two edge truss sheets;

acquiring the width and the height of the cross section of the member of the edge truss sheet according to the internal force of the member of the edge truss sheet;

taking the width and the height as the initial width W of the section of the rod piece of the main truss sheet (10)_{Master and slave}And an initial height H_{Master and slave}。

9. The method for designing the truss of the wide deck variant truss type suspension bridge steel truss girder according to claim 8, further comprising the step of obtaining the internal force of the rod members of the first side truss piece (20) and the second side truss piece (21), specifically as follows:

establishing an optimization model of the steel truss girder, wherein an edge span area (2) in the optimization model comprises two first edge truss sheets (20) and a second edge truss sheet (21);

according to the area of the cross section of the member of the edge truss piece, W_{Edge 1}And H_{Edge 1}And W_{Edge 2}And H_{Edge 2}Is provided withDetermining a preliminary thickness D 'of a bar member of the first and second side rail sheets (20, 21)'_{Edge 1}And D'_{Edge 2}；

According to W_{Edge 1}、H_{Edge 1}、D'_{Edge 1}And W_{Edge 2}、H_{Edge 2}、D'_{Edge 2}And acquiring the internal force of the rod pieces of the first side truss piece (20) and the second side truss piece (21).

10. The method for designing the truss of the wide deck variable truss type suspension bridge steel truss girder according to claim 5, wherein the method further comprises the steps of:

obtaining the cross sections of the two side cross beams (22) according to the internal force of the two side cross beams (22);

and obtaining the height of the side cross beam (22) according to the sectional area.

Technical Field

The application relates to the technical field of bridge construction, in particular to a steel truss girder of a wide bridge deck variable truss piece type suspension bridge and a design method of truss pieces.

Background

In recent years, with the high-speed development of social economy in China, vehicles are more and more, bridge decks are wider and wider, bridges are wider and larger, and suspension bridges have the advantages of large span, light weight, high bearing capacity and the like, and become the primary structural form of choice for super-large span bridges. The conventional suspension bridge steel truss girder is designed by adopting the following ideas:

the main stress structure of the steel truss girder is a main truss and a bridge deck, the section of the main truss is mainly determined by the profile size (the width and the height of a plate) and the plate thickness, and the profile size is controlled by the maximum internal force of the main truss. For the wide bridge surface suspension bridge steel truss girder with the side span, the steel truss girder is distributed in two areas of the side span and the middle span. The mid-span area steel truss girder is supported by slings, the span of the steel truss girder between the slings is smaller, and the internal force of the main truss is smaller; the steel truss girder in the side span area is not supported by a sling, the span of the steel truss girder is very large, and the internal force of the main truss girder is large.

In the conventional suspension bridge steel truss girder design, the steel truss girders in the side span and middle span areas are designed by adopting uniform main truss section contour dimension, and the contour dimension is controlled and designed by the side span maximum internal force rod piece. However, the side span region is short, the mid-span region is long, and the steel consumption of the full bridge is mainly determined by the mid-span region. If the cross section profile size of the side-span main girder is adopted, the steel consumption of the mid-span area is higher, and further the steel consumption of the full bridge is higher. Therefore, the conventional design idea of the steel truss girder of the wide-deck suspension bridge leads the section outline size of the main truss to be larger and the steel consumption of the full bridge to be higher. In addition, in the design of the steel truss girder of the railway suspension bridge, the design specification has strict requirements on the corner of the girder end, the span of the bridge deck beam of the side span is large, the transverse deformation is large, and the smoothness of the rail is not facilitated.

Disclosure of Invention

The embodiment of the application provides a wide bridge span becomes truss piece formula suspension bridge steel truss girder and design method of purlin piece to solve among the correlation technique border span and well span regional steel truss and all adopt unified main purlin section profile size, make main purlin section profile size bigger than normal, the steel volume for full-bridge is higher than normal, and the bridge floor crossbeam span of border span is great, and lateral deformation is great, is unfavorable for the problem of track smoothness.

In a first aspect, a steel truss girder for a wide bridge deck variable truss sheet type suspension bridge is provided, which includes:

the middle span area comprises two main truss sheets arranged at intervals along the transverse bridge direction and a main cross beam transversely arranged between the two main truss sheets;

two side span areas, two side span areas are located along the longitudinal bridge to the branch in the both ends of stride district in, the side span area includes:

-two first side girder pieces, which are arranged at a distance along the transverse direction and extend along the longitudinal direction to be connected with the two main girder pieces;

-a second side web between two of said first side webs and extending in a longitudinal bridging direction to join said main beam;

two side beams, each of which is arranged transversely between the second side beam piece and the two first side beam pieces and extends in the longitudinal bridge direction to be connected to the main beam.

In some embodiments, the second edge web is intermediate the two first edge webs.

In some embodiments, the main truss panel, the first side truss panel and the second side truss panel each comprise: the upper chord member and the lower chord member are arranged at intervals along the height direction of the steel truss girder, and are connected with a plurality of web members between the upper chord member and the lower chord member.

In some embodiments:

the main cross beam comprises a first main cross beam and a second main cross beam, the first main cross beam is arranged between the upper chords of the two main truss sheets, and the second main cross beam is arranged between the lower chords of the two main truss sheets;

the side cross beam comprises a first side cross beam and a second side cross beam, the first side cross beam is arranged between the first side truss piece and the upper chord of the second side truss piece, and the second side cross beam is arranged between the first side truss piece and the lower chord of the second side truss piece.

In a second aspect, there is provided a method for designing the girder of the steel girder of the wide-deck variable-girder type suspension bridge, which includes the following steps:

reducing the initial width W of the section of the bar of the main girder_{Master and slave}And an initial height H_{Master and slave}To obtain the width to be optimizedAnd height

Will be provided withAndan initial width W of a cross section of the bar member as the first side girder piece_{Edge 1}And an initial height H_{Edge 1}(ii) a And will beAn initial width W of a cross section of the bar member as the second side girder piece_{Edge 2}；

According to the first edge truss sheet and the second edgeInternal force of the members of the webs, W_{Edge 1}，H_{Edge 1}，W_{Edge 2}And the initial height H of the section of the rod piece of the second edge truss piece_{Edge 2}Obtaining the initial thickness D of the section of the rod piece of the first side truss piece and the second side truss piece_Edge；

Judgment of D_EdgeWhether a threshold value is exceeded;

if greater than the threshold, increaseAndrepeating the above steps until D_EdgeSubstantially equal to the threshold;

if less than the threshold, continue to decreaseAndrepeating the above steps until D_EdgeSubstantially equal to said threshold value.

In some embodiments, the main truss panel, the first side truss panel and the second side truss panel each comprise: the upper chord member and the lower chord member are arranged at intervals along the height direction of the steel truss girder, and are connected with a plurality of web members between the upper chord member and the lower chord member.

In some embodiments, the design method specifically includes the steps of:

respectively reducing the initial width W of the sections of the upper chord and the lower chord of the main truss sheet_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}And respectively as the width to be optimized of the upper chord and lower chord sections of the main truss sheetAndand height to be optimizedAnd

will be provided withAndthe initial widths W of the sections of the upper chord and the lower chord of the first edge truss sheet are respectively taken as_{On the edge 1}And W_{Under the edge 1}And the initial width W of the cross section of the upper chord and the lower chord of the second edge truss piece_{On the edge 2}And W_{Under the edge 2}(ii) a And will beAndthe initial height H of the sections of the upper chord and the lower chord of the first side truss sheet is respectively taken as_{On the edge 1}And H_{Under the edge 1}；

According to the internal forces of the upper chord and the lower chord of the first edge truss piece, and W_{On the edge 1}，W_{Under the edge 1}，H_{On the edge 1}And H_{Under the edge 1}Obtaining the initial thickness D of the sections of the upper chord and the lower chord of the first edge truss piece_{On the edge 1}And D_{Under the edge 1}；

According to the internal forces of the upper chord and the lower chord of the second edge truss sheet, W_{On the edge 2}And W_{Under the edge 2}And the initial height H of the upper chord and the lower chord of the second edge truss piece_{On the edge 2}And H_{Under the edge 2}Obtaining the initial thickness D of the sections of the upper chord and the lower chord of the second edge truss piece_{On the edge 2}And D_{Under the edge 2}；

Judgment of D_{On the edge 1}And D_{Under the edge 1}And D_{On the edge 2}And D_{Under the edge 2}Whether a threshold value is exceeded;

if D is_{On the edge 1}Or D_{On the edge 2}Beyond the threshold, increaseAndrepeating the above steps until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{Under the edge 1}Or D_{Under the edge 2}Beyond the threshold, increaseAndrepeating the above steps until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to the threshold;

if D is_{On the edge 1}Or D_{On the edge 2}Less than the threshold, continue to decreaseAndrepeating the above steps until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{Under the edge 1}Or D_{Under the edge 2}Less than the threshold, continue to decreaseAndrepeating the above steps until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to said threshold value.

In some embodiments, the design method further comprises obtaining W_{Master and slave}And H_{Master and slave}The method comprises the following specific steps:

establishing an initial model of the steel truss girder, wherein an edge span area in the initial model comprises two edge truss sheets;

acquiring the width and the height of the cross section of the member of the edge truss sheet according to the internal force of the member of the edge truss sheet;

taking the width and the height as the initial width W of the section of the rod piece of the main truss sheet_{Master and slave}And an initial height H_{Master and slave}。

In some embodiments, the design method further comprises the step of obtaining an internal force of the bar elements of the first and second side rail pieces, specifically as follows:

establishing an optimization model of the steel truss girder, wherein an edge span area in the optimization model comprises two first edge truss pieces and a second edge truss piece;

according to the area of the cross section of the member of the edge truss piece, W_{Edge 1}And H_{Edge 1}And W_{Edge 2}And H_{Edge 2}Setting a preliminary thickness D 'of the bar member of the first side rail sheet and the second side rail sheet'_{Edge 1}And D'_{Edge 2}；

According to W_{Edge 1}、H_{Edge 1}、D'_{Edge 1}And W_{Edge 2}、H_{Edge 2}、D'_{Edge 2}And acquiring the internal force of the rod pieces of the first side truss piece and the second side truss piece.

In some embodiments, the design method further comprises the steps of:

obtaining the sectional areas of the two side cross beams according to the internal forces of the two side cross beams;

and obtaining the height of the side beam according to the sectional area.

The beneficial effect that technical scheme that this application provided brought includes: the suspension bridge steel truss girder's of this application embodiment limit span district increases a truss piece, that is to say second limit truss piece, the second limit truss piece that increases has shared the internal force of two truss pieces originally in the limit span district, can reduce the internal force of every truss piece, consequently, can be with the little point of the member cross section contour dimension design of the first limit truss piece in limit span district and second limit truss piece, the member cross section contour dimension of the main truss piece in the span district that uses the member cross section of the truss piece in limit span district as the benchmark then also is less than conventional, consequently, the steel consumption of the main truss piece in the span district in can greatly reduced to reduce the steel consumption of full-bridge. Moreover, because the second edge truss piece is additionally arranged in the edge span area, the span of the edge beam of the edge span area is reduced, the transverse deformation of the edge beam is reduced, and the smoothness of the track is facilitated.

The embodiment of the application provides a wide bridge face variable truss type suspension bridge steel truss girder and a design method of truss sheets, wherein one truss sheet, namely a second side truss sheet, is added in a side span area of the suspension bridge steel truss girder in the embodiment of the application, the added second side truss sheet shares internal forces of two original truss sheets in the side span area, and the internal force of each truss sheet can be reduced, so that the rod section profile size of a first side truss sheet and a second side truss sheet in the side span area can be designed to be a small point, and the rod section profile size of a main truss sheet in a midspan area taking the rod section of the truss sheet in the side span area as a reference is smaller than that of a conventional one, so that the steel consumption of the main truss sheet in the midspan area can be greatly reduced, and the steel consumption of a full bridge is reduced; moreover, because the second edge truss piece is additionally arranged in the edge span area, the span of the edge beam of the edge span area is reduced, the steel consumption of the edge beam is reduced, the transverse deformation of the edge beam is reduced, and the smoothness of the track is facilitated.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic cross-sectional view of a midspan region of a steel truss girder of a wide deck variable truss sheet type suspension bridge provided by an embodiment of the application;

FIG. 2 is a schematic cross-sectional view of an edge span region of a steel truss girder of a wide deck variable truss type suspension bridge provided by an embodiment of the application;

FIG. 3 is a schematic structural view of a first side rail sheet provided in accordance with an embodiment of the present disclosure;

FIG. 4 is a schematic structural view of a second side rail sheet provided in accordance with an embodiment of the present application;

FIG. 5 is an enlarged view of a portion of FIG. 4 at A;

fig. 6 is a flowchart of a method for designing a truss sheet of a steel truss girder of a suspension bridge with a variable truss sheet type wide deck according to an embodiment of the present application.

In the figure: 1. a mid-span region; 10. a main truss sheet; 100. an upper chord; 101. a lower chord; 102. a web member; 11. a main cross beam; 110. a first main beam; 111. a second main beam; 2. an edge crossing region; 20. a first side gusset; 21. a second edge web; 22. a side cross member; 220. a first side beam; 221. and a second edge beam.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Example 1:

referring to fig. 1 and 2, an embodiment 1 of the present application provides a wide bridge deck variable truss sheet type suspension bridge steel truss girder, which includes a midspan region 1 and two side span regions 2, where the midspan region 1 includes two main truss sheets 10 arranged at intervals in a transverse bridge direction, and a main cross beam 11 arranged transversely between the two main truss sheets 10; the two side span areas 2 are respectively arranged at two ends of the middle span area 1 along the longitudinal bridge direction, each side span area comprises two first side truss pieces 20, a second side truss piece 21 and two side cross beams 22, and the two first side truss pieces 20 are arranged at intervals along the transverse bridge direction and respectively extend to be connected with the two main truss pieces 10 along the longitudinal bridge direction; the second side truss sheet 21 is positioned between the two first side truss sheets 20 and extends along the longitudinal bridge direction to be connected with the main cross beam 11; the two side beams 22 are respectively arranged between the second side beam piece 21 and the two first side beam pieces 20 transversely, and extend along the longitudinal bridge direction to be connected with the main beam 11.

The conventional suspension bridge steel truss girder also comprises a midspan region 1 and two side span regions 2, wherein the midspan region 1 comprises two truss sheets arranged at intervals along the transverse bridge direction, but the side span regions 2 only comprise two truss sheets arranged at intervals along the transverse bridge direction, and the section of a rod of the truss sheet of the midspan region 1 is based on the section of the rod of the truss sheet of the side span region 2, and the truss sheet of the side span region 2 is not supported by a sling, so that the internal force of the rod is large, the design of the section contour size of the rod of the truss sheet of the midspan region 1 is large, the steel consumption is large, the bridge construction cost is increased, and the waste of steel is caused.

Compared with the conventional suspension bridge steel truss girder, the suspension bridge steel truss girder of embodiment 1 of the present application has the advantages that one truss piece, that is, the second side truss piece 21, is added to the side span region 2, and the added second side truss piece 21 shares the internal forces of the two original truss pieces in the side span region 2, so that the internal force of each truss piece can be reduced, and therefore, the member section profile dimensions of the first side truss piece 20 and the second side truss piece 21 in the side span region 2 can be designed to be a small point, and then the member section profile dimension of the main truss piece 10 in the region 1 based on the member section of the truss piece in the side span region 2 is also smaller than that in the conventional one, so that the steel consumption of the main truss piece 10 in the middle span region 1 can be greatly reduced, and the steel consumption of the full bridge can be reduced. Moreover, because the second edge beam piece 21 is added to the edge span region 2 of embodiment 1, the span of the edge beam 22 of the edge span region 2 is reduced (the span of the edge beam of the edge span region 2 of two conventional beam pieces is the transverse distance between the two beam pieces, and the span of the edge beam of the edge span region 2 of embodiment 1 is the transverse distance between the first edge beam piece 20 and the second edge beam piece 21), so that the transverse deformation of the edge beam is reduced, and the smoothness of the track is facilitated.

Referring to fig. 2, further, a second side gusset 21 is positioned intermediate the two first side gusset 20.

The transverse distances between the second edge truss piece 21 and the two first edge truss pieces 20 are equal, so that the spans of the two edge cross beams 22 are also equal, and the smoothness and the stress stability of the steel truss beam are ensured.

Referring to fig. 3 and 4, further, the main girder segment 10, the first side girder segment 20 and the second side girder segment 21 each include: an upper chord 100 and a lower chord 101 provided at intervals in the height direction of the steel girder, and a plurality of web members 102 connected between the upper chord 100 and the lower chord 101.

The truss sheet of embodiment 1 of the present application is a truss structure in which the upper chord 100, the lower chord 101, and the web member 102 are driven, and the upper chord 100 and the lower chord 101 are assembled by splicing a plurality of member segments.

Referring to fig. 1 and 2, further, the main beam 11 includes a first main beam 110 and a second main beam 111, the first main beam 110 is disposed between the upper chords 100 of the two main truss pieces 10, and the second main beam 111 is disposed between the lower chords 101 of the two main truss pieces 10; the side member 22 includes a first side member 220 and a second side member 221, the first side member 220 is provided between the upper chords 100 of the first and second side members 20 and 21, and the second side member 221 is provided between the lower chords 101 of the first and second side members 20 and 21.

The suspension bridge steel truss of embodiment 1 of this application is double-deck track bridge, and first main beam 110 and second main beam 111 divide into two-layer from top to bottom, and first main beam 110 and second main beam 111 homoenergetic are driven a vehicle.

Referring to fig. 5, the second side gusset 21 extends a length distance toward the midspan region 1 at the main tower to facilitate the transition of forces within the second side gusset 21.

Example 2:

referring to fig. 6, embodiment 2 of the present application provides a method for designing a truss sheet of a steel truss girder of a wide bridge deck variable truss sheet type suspension bridge, which includes the following steps:

600: reducing the initial width W of the beam section of the main web 10_{Master and slave}And an initial height H_{Master and slave}To obtain the width to be optimizedAnd height

Initial section of the bar due to conventional main girder 10Width W_{Master and slave}And an initial height H_{Master and slave}Are designed with reference to the width and height of the beam section of the beam of only the side span 2 of the two beams, resulting in the initial width W of the beam section of the conventional main beam 10_{Master and slave}And an initial height H_{Master and slave}Too large, too small thickness, increasing steel consumption; therefore, in example 1 of the present application, the initial width W of the bar section of the main girder 10 is set to be smaller_{Master and slave}And an initial height H_{Master and slave}To reduce the amount of steel used for the main truss sheet 10.

601: will be provided withAndinitial width W of a bar section as a first side girder piece 20_{Edge 1}And an initial height H_{Edge 1}(ii) a And will beInitial width W of a member section as the second side girder piece 21_{Edge 2}；

Since the edge span region 2 of the embodiment 2 has three truss pieces, compared with the conventional steel truss girder, one truss piece is added, so that the initial width W of the member section of the first edge truss piece 20_{Edge 1}And an initial height H_{Edge 1}Can be reduced appropriately, thereby reducing the initial width W of the bar section of the first side girder piece 20_{Edge 1}And an initial height H_{Edge 1}With the width of the main web 10 to be optimizedAnd heightDesigned for reference, the initial width W of the member section of the first side truss sheet 20 is reduced_{Edge 1}And an initial height H_{Edge 1}Meanwhile, the width and the height of the member bars of the truss sheets of the mid-span region 1 and the side-span region 2 of the full bridge can be kept basically consistent.

Furthermore, due to the bridge deckThere is a slope, the second side girder piece 21 is located between the two first side girder pieces 20, then the height of the member section of the second side girder piece 21 is higher than that of the first side girder piece 20, and the height of the member section of the second side girder piece 21 is known, only the width of the main girder piece 10 to be optimized needs to be adjustedInitial width W of a member section as the second side girder piece 21_{Edge 2}And (4) finishing.

602: according to the internal force of the bar member of the first side girder piece 20 and the second side girder piece 21, W_{Edge 1}，H_{Edge 1}，W_{Edge 2}And the initial height H of the bar section of the second edge beam piece 21_{Edge 2}Obtaining an initial thickness D of the cross section of the bar member of the first side girder piece 20 and the second side girder piece 21_Edge；

Knowing the loads of the bar members of the first side girder piece 20 and the second side girder piece 21, and combining the internal forces of the bar members of the first side girder piece 20 and the second side girder piece 21, the sectional area of the bar members of the first side girder piece 20 and the second side girder piece 21 can be obtained, thereby obtaining the initial thickness D of the section of the bar members of the first side girder piece 20 and the second side girder piece 21_Edge。

603: judgment of D_EdgeWhether a threshold value is exceeded;

due to the initial width W of the beam section of the main girder 10_{Master and slave}And an initial height H_{Master and slave}The more the reduction, the initial thickness D of the bar section of the first side rail piece 20 and the second side rail piece 21_EdgeWill be larger, but D_EdgeThe threshold value can not be exceeded, and the performance indexes of the rod piece can be reduced if the threshold value is exceeded.

604: if greater than the threshold, increaseAndand repeating the steps 601-603 until D_EdgeSubstantially equal to the threshold;

threshold value of embodiment 2 of the present applicationSet to 50 mm. If D is_EdgeGreater than 50mm indicates an initial width W of the bar section of the first side rail piece 20_{Edge 1}And an initial height H_{Edge 1}Too small, then it needs to be increasedAndto increase the initial width W of the bar section of the first side girder piece 20_{Edge 1}And an initial width height H_{Edge 1}And the initial width W of the bar section of the second edge beam piece 21_{Edge 2}The initial thickness D of the cross-section of the bar member of the first side rail piece 20 and the second side rail piece 21 can be reduced_EdgeUp to D_EdgeSubstantially equal to 50mm, for example 48-52 mm.

605: if less than the threshold, continue to decreaseAndand repeating the steps 601-603 until D_EdgeSubstantially equal to the threshold value.

If D is_EdgeLess than 50mm indicates the initial width W of the bar section of the main girder 10_{Master and slave}And an initial height H_{Master and slave}Can continue to be reduced, and then is reduced againAndto reduce again the initial width W of the bar section of the first edge beam piece 20_{Edge 1}And an initial height H_{Edge 1}And the initial width W of the bar section of the second edge beam piece 21_{Edge 2}Up to D_EdgeApproaching 50 mm.

Referring to fig. 3 and 4, further, the main girder segment 10, the first side girder segment 20 and the second side girder segment 21 each include: an upper chord 100 and a lower chord 101 provided at intervals in the height direction of the steel girder, and a plurality of web members 102 connected between the upper chord 100 and the lower chord 101.

The truss sheet of embodiment 2 of the present application is a truss structure in which the upper chord 100, the lower chord 101, and the web member 102 are driven, and the upper chord 100 and the lower chord 101 are assembled by splicing a plurality of member segments.

Furthermore, the design method specifically comprises the following steps:

700: the initial width W of the sections of the upper chord 100 and the lower chord 101 of the main truss 10 is reduced_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}And respectively as the width to be optimized of the sections of the upper chord 100 and the lower chord 101 of the main truss 10Andand height to be optimizedAnd

due to the initial width W of the cross-section of the upper chord 100 and the lower chord 101 of the conventional main girder 10_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}Are designed based on the width and height of the upper chord 100 and lower chord 101 sections of the webs only in the side span region 2 of the two webs, resulting in the initial width W of the upper chord 100 and lower chord 101 sections of the conventional main web 10_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}The thickness is too small, and the steel consumption is increased; therefore, in the embodiment 2 of the present application, the initial width W of the cross section of the upper chord 100 and the lower chord 101 of the main truss 10 is set_{On the main}And W_{Under main}And an initial height H_{On the main}And H_{Under main}Are all reduced toThe amount of steel used for the main truss web 10 is low.

701: will be provided withAndthe initial width W of the cross section of the upper chord 100 and the lower chord 101 of the first side truss sheet 20_{On the edge 1}And W_{Under the edge 1}And the initial width W of the cross section of the upper chord 100 and the lower chord 101 of the second edge truss piece 21_{On the edge 2}And W_{Under the edge 2}(ii) a And will beAndthe initial height H of the cross section of the upper chord 100 and the lower chord 101 of the first side truss sheet 20_{On the edge 1}And H_{Under the edge 1}；

The width and height of the cross section of the upper chord 100 of the first side truss piece 20 and the second side truss piece 21 in embodiment 2 of the present application are determined by the cross section of the upper chord 100 of the main truss piece 10Anddesigning for a benchmark; the width and height of the lower chord 101 section of the first side truss piece 20 and the second side truss piece 21 are determined by the section of the lower chord 101 of the main truss piece 10Anddesign for benchmark.

702: according to the internal forces of the upper chord 100 and the lower chord 101 of the first side truss piece 20, and W_{On the edge 1}，W_{Under the edge 1}，H_{On the edge 1}And H_{Under the edge 1}Obtaining the initial thickness D of the cross section of the upper chord 100 and the lower chord 101 of the first side truss piece 20_{On the edge 1}And D_{Under the edge 1}；

Knowing the loads of the upper chord 100 and the lower chord 101 of the first side truss piece 20 and combining the internal forces of the upper chord 100 and the lower chord 101 of the first side truss piece 20, the cross-sectional areas of the upper chord 100 and the lower chord 101 of the first side truss piece 20 can be obtained, and thus the initial thickness D of the cross-section of the upper chord 100 and the lower chord 10 of the first side truss piece 20 can be obtained_{On the edge 1}And D_{Under the edge 1}。

703: according to the internal forces of the upper chord 100 and the lower chord 101 of the second edge truss piece 21, W_{On the edge 2}And W_{Under the edge 2}And the initial height H of the upper chord 100 and the lower chord 101 of the second edge truss panel 21_{On the edge 2}And H_{Under the edge 2}Obtaining the initial thickness D of the cross section of the upper chord 100 and the lower chord 101 of the second side truss piece 21_{On the edge 2}And D_{Under the edge 2}；

Knowing the loads of the upper chord 100 and the lower chord 101 of the second side truss piece 21 and combining the internal forces of the upper chord 100 and the lower chord 101 of the second side truss piece 21, the sectional areas of the upper chord 100 and the lower chord 101 of the second side truss piece 21 can be obtained, so as to obtain the initial thickness D of the section of the upper chord 100 and the lower chord 10 of the second side truss piece 21_{On the edge 2}And D_{Under the edge 2}。

704: judgment of D_{On the edge 1}And D_{Under the edge 1}And D_{On the edge 2}And D_{Under the edge 2}Whether a threshold value is exceeded;

705: if D is_{On the edge 1}Or D_{On the edge 2}Beyond the threshold, increaseAndand repeating steps 701-704 until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{On the edge 1}Or D_{On the edge 2}Exceeding the threshold value indicates the initial width W of the section of the upper chord 100 of the main girder 10_{On the main}And an initial height H_{On the main}Too small, then it needs to be increasedAndto increase the W of the cross-section of the upper chord 100 of the first side rail piece 20_{On the edge 1}And H_{On the edge 1}And the initial width W of the cross section of the upper chord 100 of the second edge truss piece 21_{On the edge 2}The initial thickness D of the cross-section of the top chord 100 of the first side rail piece 20 and the second side rail piece 21 can be reduced_{On the edge 1}And D_{On the edge 2}Up to D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold value.

706: if D is_{Under the edge 1}Or D_{Under the edge 2}Beyond the threshold, increaseAndand repeating steps 701-704 until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to the threshold;

if D is_{Under the edge 1}Or D_{Under the edge 2}Exceeding the threshold value indicates the initial width W of the section of the lower chord 101 of the main girder 10_{On the main}And an initial height H_{On the main}Too small, then it needs to be increasedAndto increase the W of the cross-section of the lower chord 101 of the first side girder piece 20_{Under the edge 1}And H_{Under the edge 1}And the initial width W of the cross section of the lower chord 101 of the second edge truss piece 21_{Under the edge 2}The initial thickness D of the cross-section of the lower chord 101 of the first side rail piece 20 and the second side rail piece 21 can be reduced_{Under the edge 1}Or D_{Under the edge 2}Up to D_{Under the edge 1}Or D_{Under the edge 2}Is substantially equal to the threshold value。

707: if D is_{On the edge 1}Or D_{On the edge 2}Less than the threshold, continue to decreaseAndand repeating steps 701-704 until D_{On the edge 1}And D_{On the edge 2}Substantially equal to the threshold;

if D is_{On the edge 1}Or D_{On the edge 2}Less than the threshold value, it indicates the initial width W of the section of the upper chord 100 of the main girder 10_{On the main}And an initial height H_{On the main}Can continue to be reduced, and then is reduced againAndto reduce again the initial width W of the cross-section of the upper chord 100 of the first edge truss panel 20_{On the edge 1}And an initial height H_{On the edge 1}And the initial width W of the cross section of the upper chord 100 of the second edge truss piece 21_{On the edge 2}Up to D_{On the edge 1}And D_{On the edge 2}The threshold is approached.

708: if D is_{Under the edge 1}Or D_{Under the edge 2}Less than the threshold, continue to decreaseAndand repeating steps 701-704 until D_{Under the edge 1}And D_{Under the edge 2}Substantially equal to the threshold value.

If D is_{Under the edge 1}Or D_{Under the edge 2}Less than the threshold value, it indicates the initial width W of the cross section of the lower chord 101 of the main truss 10_{On the main}And an initial height H_{On the main}Can continue to be reduced, and then is reduced againAndto reduce again the initial width W of the cross-section of the lower chord 101 of the first edge truss panel 20_{Under the edge 1}And an initial height H_{Under the edge 1}And the initial width W of the cross section of the lower chord 101 of the second edge truss piece 21_{Under the edge 2}Up to D_{Under the edge 1}And D_{Under the edge 2}The threshold is approached.

Further, the initial width W of the bar section of the main girder 10 in step 600_{Master and slave}And an initial height H_{Master and slave}The method comprises the following steps:

800: establishing an initial model of the steel truss girder, wherein an edge span area 2 in the initial model comprises two edge truss sheets;

the initial model here is a conventional suspension bridge steel truss, also comprising a mid-span zone 1 and two side-span zones 2, the mid-span zone 1 comprising two truss sheets spaced apart along the transverse bridge direction, but the side-span zones 2 comprising only two side truss sheets spaced apart along the transverse bridge direction.

801: acquiring the width and the height of the section of the rod piece of the edge truss piece according to the internal force of the rod piece of the edge truss piece;

the load of the member bar of the side truss sheet is known, and the width and the height of the section of the member bar of the side truss sheet can be obtained by combining the internal force of the member bar of the side truss sheet.

802: the width and height are used as the initial width W of the section of the bar member of the main truss 10_{Master and slave}And an initial height H_{Master and slave}。

The width and height of the cross section of the member of the side girder piece are used as the initial width W of the cross section of the member of the main girder piece 10_{Master and slave}And an initial height H_{Master and slave}。

Further, the internal force of the bar member of the first side truss panel 20 and the second side truss panel 21 in step 602 is obtained according to the following steps:

900: establishing an optimization model of the steel truss girder, wherein an edge span area 2 in the optimization model comprises two first edge truss sheets 20 and two second edge truss sheets 21;

the optimized model of the steel truss girder is the model of the wide bridge deck variable truss piece type suspension bridge steel truss girder in the embodiment 1 of the application.

901: according to the area of the cross-section of the member of the edge truss_{Edge 1}And H_{Edge 1}And W_{Edge 2}And H_{Edge 2}The preliminary thickness D 'of the bar member of the first side rail sheet 20 and the second side rail sheet 21 is set'_{Edge 1}And D'_{Edge 2}；

Since the constant load of the bar member varies due to the addition of the second side gusset 21, the present application example 2 is made by assuming that all the bar members of the first side gusset 20 are the same thickness and D'_{Edge 1}And assuming that all the bar members of all the second side rail pieces 21 are the same in thickness and are D'_{Edge 2}。

902: according to W_{Edge 1}、H_{Edge 1}、D′_{Edge 1}And W_{Edge 2}、H_{Edge 2}、D′_{Edge 2}The internal force of the bar member of the first side girder piece 20 and the second side girder piece 21 is obtained.

Taking the first side web 20 as an example, according to W_{Edge 1}、H_{Edge 1}、D′_{Edge 1}Equivalent to the known structure of the first side girder piece 20, the internal force of each bar of the first side girder piece 20 can be obtained, and the corrected thickness of each bar of the first side girder piece 20 is obtained according to the internal force of each bar of the first side girder piece 20, and then is obtained according to W_{Edge 1}、H_{Edge 1}And correcting the thickness to obtain a corrected internal force of each bar member of the first side truss panel 20, and then obtaining an optimized thickness of each bar member of the first side truss panel 20 according to the corrected internal force. The desired or optimized thickness of each bar of the first side gusset 20 can be obtained in substantially two iterations.

Further, the design method further comprises the following steps:

606: obtaining the sectional areas of the two side beams 22 according to the internal forces of the two side beams 22;

607: the height of the side rail 22 is obtained from the sectional area.

Due to the addition of the second side girder pieces 21, the internal force of the two side girders 22 is reduced compared with the internal force of a conventional girder, and the sectional area of the side girders 22 is also reduced, so that the height of the side girders 22 can be reduced, and the steel consumption of the side girders 22 is saved.

In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

It is noted that, in the present application, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.