A mixed constraint wharf bridge crane three-span steel truss support optimization structure

Abstract

The utility model discloses a wharf bridge -type crane three -span steel truss support optimization structure of mixed constraint adopts three -span continuous steel truss form, and the supporting leg adopts mixed constraint connection mode with main truss, that is, adopts articulated constraint in longitudinal direction, adopts elastic constraint in transverse direction, adopts rigid constraint in vertical direction, and the foundation support adopts combined structure, and the upper part is spherical hinge support, the middle part is shock -absorbing rubber pad layer, and the lower part is anchor bolt group, and stiffened rib plate is arranged at each component connecting joint in structure, and the stiffened rib plate is radially arranged, and the node is provided with stiffened rib plate, the support optimization structure provided by the utility model can combine the constraint characteristics of different directions, improve the stability, the anti -seismic performance and fatigue life of structure, optimize truss stress distribution simultaneously, reduce the material consumption, to adapt to the long -term use demand under the complex working condition of port. It is suitable for large -span port bridge -type crane, and can significantly improve the safety and economy of equipment.

Description

Technical Field

[0001] This utility model relates to the field of dock equipment technology, and in particular to an optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints. Background Technology

[0002] In port loading and unloading operations, bridge cranes are widely used for lifting large cargo. The stability of their steel truss structure and the reliability of their supports directly affect the safety and service life of the equipment. Traditional dock bridge crane steel truss supports typically employ a single constraint method (such as fully rigid or fully hinged). Although the structure is simple, it presents the following technical problems in actual operation:

[0003] The constraint methods are limited and lack adaptability: fully rigid supports are prone to generating large additional stresses when the temperature changes or the foundation settles, leading to local cracking or deformation of the structure; although fully articulated supports can release some constraints, their lateral stiffness is insufficient, and they are prone to excessive swaying under wind loads or hoisting impacts, affecting the positioning accuracy of the crane.

[0004] Limited vibration damping performance of bearings: Traditional bearings mostly use rigid connections or simple rubber pads, which have poor ability to absorb dynamic loads during crane operation. Long-term use can easily lead to problems such as loose bolts and fatigue damage to the bearings.

[0005] Insufficient stress optimization of three-span continuous trusses: Existing three-span steel truss structures usually adopt a uniform height design, which fails to fully consider the difference in bending moment distribution between the mid-span and the legs, resulting in material waste or local stress concentration.

[0006] The nodes are simple in construction and prone to stress concentration: Traditional truss nodes mostly use ordinary welding or bolt connections, lacking optimized design. Under alternating loads, weld cracking or bolt loosening is likely to occur, affecting the durability of the structure.

[0007] Therefore, there is an urgent need for a three-span steel truss support structure for dock bridge cranes that can provide stability. Utility Model Content

[0008] In view of this, the purpose of this utility model is to provide an optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints. This support structure can combine constraint characteristics in different directions to improve the stability of the structure.

[0009] To achieve the above objectives, this utility model provides the following technical solution:

[0010] This utility model provides an optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints. The structure adopts a three-span continuous steel truss form, consisting of two side spans and one middle span. The truss height of each span gradually increases from the middle of the span towards the legs. The legs and the main truss are connected by a hybrid constraint method, including: hinged constraints in the longitudinal direction; elastic constraints in the transverse direction; and rigid constraints in the vertical direction. The foundation support adopts a combined structure, including: a ball joint support at the top; a shock-absorbing rubber pad layer in the middle; and an anchor bolt group at the bottom. Stiffening ribs are provided at the connection nodes of each component in the structure.

[0011] Furthermore, the span ratio of the side span to the middle span of the three-span continuous steel truss is 0.6-0.8:1, and the truss height variation gradient is 1:15-1:20.

[0012] Furthermore, the elastic constraint adopts a disc spring assembly with a stiffness coefficient of 500-800kN / mm and a pre-compression amount of 5-10mm.

[0013] Furthermore, the rotation angle of the ball joint support is designed to be ±3°, and the spherical pad is made of a self-lubricating composite material.

[0014] Furthermore, the shock-absorbing rubber pad is a composite structure of natural rubber and lead core, with the diameter of the lead core being 1 / 3 to 1 / 2 of the thickness of the rubber pad.

[0015] Furthermore, the stiffening ribs are arranged radially, and the thickness of the ribs is 0.8-1.2 times the thickness of the thicker plate of the adjacent component.

[0016] Furthermore, the cross-sectional shape of the support leg is trapezoidal, with the width of the upper base being 0.8-1.2 times the width of the lower base, and the height being 1 / 10-1 / 15 of the span.

[0017] Furthermore, the connection node is constructed with a T-shaped reinforcing rib, the thickness of which is 1.2-1.5 times the thickness of the node plate, and a drainage hole is provided at the node.

[0018] Furthermore, the steel truss is made of corrosion-resistant high-strength steel with a yield strength of not less than 355 MPa, and its surface is coated with an epoxy resin anti-corrosion coating.

[0019] The beneficial effects of this utility model are as follows:

[0020] This utility model provides an optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints. It adopts a three-span continuous steel truss form, with the legs and main truss connected by a hybrid constraint method: hinged constraints in the longitudinal direction, elastic constraints in the transverse direction, and rigid constraints in the vertical direction. The foundation support uses a composite structure: a ball-joint support at the top, a damping rubber pad in the middle, and an anchor bolt group at the bottom. In the three-dimensional model of this structure, the connection nodes of each component can be parametrically modeled, and stiffening ribs are set at the nodes. The optimized support structure provided by this utility model can combine the constraint characteristics in different directions to improve the stability, seismic performance, and fatigue life of the structure, while optimizing the stress distribution of the truss and reducing material usage to meet the long-term use requirements under complex port conditions. It is suitable for large-span port bridge cranes and can significantly improve the safety and economy of the equipment. Through optimized design using hybrid constraints, composite supports, and variable cross-section trusses, it has the following characteristics: Improved stability: Hybrid constraints adapt to different working conditions and reduce additional stress. Enhanced seismic resistance: Elastic constraints + damping supports effectively absorb vibrations. Optimized stress distribution: Variable cross-section trusses reduce material usage and improve structural efficiency. Extended lifespan: Optimized joints reduce stress concentration and fatigue damage.

[0021] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0022] To make the objectives, technical solutions, and beneficial effects of this utility model clearer, the following drawings are provided for illustration:

[0023] Figure 1 Front view of the optimized structure for a three-span steel truss support.

[0024] Figure 2 Optimize the side view of the three-span steel truss support structure.

[0025] Figure 3 A three-dimensional diagram of the optimized structure of the support for a three-span steel truss.

[0026] Figure 4 This is the cross-sectional view of the main beam.

[0027] Figure 5 This is the internal structure of the top-level main beam.

[0028] Figure 6 This is a three-dimensional model of the main beam cross-section.

[0029] Figure 7 This is a cross-sectional view of the top-level main beam.

[0030] In the diagram, 1 is the superstructure, 2 is the cantilever end, 3 is the cantilever steel structure foundation; 11 is the diaphragm; 12 is the supporting structure; 13 is the angle steel; and 14 is the second track beam. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0032] like Figure 1 As shown in this embodiment, an optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints is provided. The structure adopts a three-span continuous steel truss form, consisting of two side spans and one middle span. The truss height of each span gradually increases from the middle of the span towards the legs. The legs and the main truss are connected by a hybrid constraint method, including hinged constraints in the longitudinal direction, elastic constraints in the transverse direction, and rigid constraints in the vertical direction. The foundation support adopts a composite structure, including a ball joint support at the top, a damping rubber pad in the middle, and an anchor bolt group at the bottom. Stiffening ribs are provided at the connection nodes of each component in the structure. The stiffening ribs are arranged radially, and the thickness of the ribs is 0.8-1.2 times the thickness of the thicker plate of the adjacent component.

[0033] The upper structure of the steel truss support provided in this embodiment is a box-type steel structure, which can be equipped with a double-span bridge crane system. Multiple legs are set at the lower part of the box-type steel structure to form a cantilever steel structure foundation. The box-type steel structure extends horizontally to form a cantilever end.

[0034] In this embodiment, the span ratio of the side span to the middle span of the three-span continuous steel truss is 0.6-0.8:1, and the truss height variation gradient is 1:15-1:20. The elastic constraint adopts a disc spring assembly with a stiffness coefficient of 500-800kN / mm and a pre-compression of 5-10mm. The rotation angle of the ball joint support is designed to be ±3°, and the spherical pad is made of self-lubricating composite material. The damping rubber pad is a composite structure of natural rubber and lead core, and the diameter of the lead core is 1 / 3-1 / 2 of the thickness of the rubber pad. A three-dimensional model is constructed parametrically, and the stiffening ribs at the nodes in the model are arranged radially, with the rib thickness being 0.8-1.2 times the thickness of the thicker plate of the adjacent member.

[0035] like Figure 2As shown, this embodiment of the three-span steel truss consists of two side spans and one middle span, forming a continuous beam structure suitable for large-span port bridge cranes. The truss height gradually increases from the mid-span towards the legs, creating a variable cross-section truss to accommodate different bending moment distributions. The preferred span ratio between the side spans and the middle span is 0.6-0.8:1 to ensure balanced stress distribution. The truss height variation gradient is 1:15-1:20 to ensure a reasonable transition in stiffness. This variable height design optimizes truss stress distribution, reduces material usage, and minimizes stress concentration. Compared to traditional constant-height trusses, it can reduce steel usage by 10%-15% while improving bending and torsional stiffness.

[0036] In this embodiment, the outriggers employ a hybrid constraint connection, specifically including:

[0037] Longitudinal articulation constraint: Pin connections are used in the longitudinal direction (along the crane track) to allow the outriggers to expand and contract freely with temperature changes or foundation settlement. This releases longitudinal constraints and avoids additional structural stress caused by thermal expansion and contraction or uneven foundation settlement. It also reduces structural deformation and improves long-term stability.

[0038] Lateral elastic constraint: Disc springs with a stiffness coefficient of 500-800 kN / mm and a pre-compression of 5-10 mm are used in the lateral direction (perpendicular to the track direction). This provides controllable lateral stiffness, resisting wind loads and lifting impacts while absorbing vibration energy. Compared to traditional rigid constraints, lateral vibration can be reduced by 20%-30%, improving the smoothness of crane operation.

[0039] Vertical rigid constraint: High-strength bolts are used for vertical fixation to ensure no relative displacement between the outriggers and the main truss. This guarantees the vertical stability of the crane when lifting heavy objects. It also prevents the outriggers from settling or shifting under heavy loads, improving safety.

[0040] like Figure 3 As shown, in this embodiment, the foundation support adopts a three-layer composite structure, which includes, from top to bottom:

[0041] Spherical hinge bearing: Utilizing a self-lubricating composite material liner, it allows for a rotation angle of ±3°. It adapts to slight foundation inclinations, preventing excessive localized pressure on the bearing. Compared to traditional fixed bearings, it reduces stress concentration by 15%-20%, extending service life.

[0042] Vibration-damping rubber pad layer: Utilizing a composite structure of natural rubber and a lead core, the lead core diameter is 1 / 3 to 1 / 2 the thickness of the rubber layer. It absorbs the impact load from crane operation, reducing vibrations transmitted to the foundation. Compared to ordinary rubber pads, its vibration damping efficiency is increased by 30%-40%, reducing equipment fatigue damage.

[0043] Anchor bolt assembly: Employs high-strength prestressed anchor bolts for reliable connection to the concrete foundation. Provides stable foundation fixation and prevents support slippage. Enhances overall overturning resistance and is suitable for strong wind environments in ports.

[0044] In this embodiment, the truss nodes are modeled parametrically to ensure reasonable stress distribution, specifically including:

[0045] Stiffening ribs: Arranged radially, with a thickness 0.8-1.2 times that of the thicker plate of the adjacent member. They enhance joint stiffness and prevent local buckling. Compared to traditional joints, stress concentration is reduced by 25%-35%, improving fatigue life.

[0046] In this embodiment, the main beams of the truss are horizontally arranged at the bottom of the truss, serving as the core load-bearing beams. They bear the lifting loads of the crane and the self-weight of the equipment, and transmit vertical forces to the outriggers. They resist mid-span bending moments and prevent truss sagging deformation. The use of box-section or I-section design improves bending stiffness and stability.

[0047] The steel pipe cable-stayed structure connects the main beam to the top structure at an incline, and consists of a front cable-stayed structure and lateral cable-stayed rods. The front cable-stayed structure resists the forward tilting moment of the crane and prevents the front end of the main beam from sinking. The lateral cable-stayed rods provide lateral stability and resist lateral forces caused by wind loads and eccentric loading during hoisting. The hollow steel pipe structure reduces its self-weight while ensuring compressive / tensile strength. The inclination angle is designed to be 45°-60° to optimize the force transmission path.

[0048] The top-floor beams are horizontally arranged at the top of the truss and connect to the upper end of the cable-stayed structure. They integrate the upper anchoring points of the cable-stayed structure, forming a closed load-bearing system. This system bears the loads of the equipment platform (such as drive mechanisms and control cabinets) and distributes them to the main beams. The truss-type beam design reduces weight and improves torsional resistance.

[0049] The top-floor connection point links the cable-stayed structure to the top-floor beam. This efficiently transfers the tension / compression forces from the cable-stayed structure to the top-floor beam. Stiffening ribs prevent local buckling at the joint. Radial ribs, 1.0-1.2 times the thickness of adjacent members, are welded to the joint area, significantly reducing stress concentration.

[0050] In this embodiment, the superstructure is mainly a box-type steel structure, consisting of 8 supporting columns and a horizontal frame. The horizontal frame includes two main bridge crane beams and front and rear end beams. The main beams span land and water. QU120 steel rails are laid on the upper flange of the main beams, and a 1000-ton bridge crane runs on the main beams. QU80 rails are laid on the trapezoidal structure extending from the lower flange of the main beams, and a 100-ton bridge crane runs on the rails above the trapezoidal structure.

[0051] The main beam is a thin-walled box girder structure with two types of cross-sections: a rectangular section of 4800×2000mm on the left and a rectangular section of 1000×940mm on the right. The main beam is surrounded by four thin-walled steel plates, with two different shapes of transverse diaphragms inside. Angle steel is welded between the diaphragms, and the spacing between the ribs is unequal, shortening at connections with other components.

[0052] The diaphragm consists of a left diaphragm and a right diaphragm. The left diaphragm contains three steel pipes connected in an isosceles triangle. The right diaphragm is a 10mm thick irregularly shaped steel plate. During modeling, the missing areas of the diaphragms need to be filled in and fixed to the angle steel.

[0053] The main beam is a thin-walled box girder structure with two types of cross-sections: a rectangular cross-section of 4800×2000mm on the left and a rectangular cross-section of 1000×940mm on the right. Figure 4 As shown, Figure 4 Main beam cross-section diagram. The main beam is surrounded by four thin-walled steel plates, with two different shaped transverse diaphragms inside. Angle steel is welded between the transverse diaphragms. The transverse diaphragms improve the overall stiffness of the beam cross-section; the internal supporting structure of the transverse diaphragms improves their stiffness; the angle steel connects the various transverse diaphragms, improving overall integrity and increasing structural stiffness; a second track beam can also be installed as the track foundation for a small crane.

[0054] The empty areas around the diaphragms are pre-reserved welding points for the angle steel during assembly. These empty areas will be filled with angle steel after welding and fixed together. The components are then assembled after stretching the cross-section. The orange diaphragm structure is more complex, featuring a 12mm thick cladding plate in the middle of a 20mm rib, with three hollow cylinders forming an isosceles triangle connected inside the cladding plate. The yellow diaphragm on the right is a 10mm thick irregularly shaped steel plate.

[0055] Angle steel is welded between the ribs. The spacing between the ribs is unequal, and the spacing between the transverse diaphragms at the connections with other components is also shortened. For example... Figure 5 As shown, Figure 5 Two types of transverse diaphragms are evenly distributed between the columns.

[0056] The top-level main beam is a thin-walled box girder structure with two different cross-sections, measuring 2400×1238mm and 1800×1234mm respectively. The structure is relatively simple, with thin-walled steel plates on all sides and reinforcing transverse diaphragms at varying intervals in the middle. The treatment of these transverse diaphragms is the same as that of the main beam transverse diaphragms.

[0057] The transverse diaphragms inside the top-level main beam are hollow steel plates (10mm thick on the left and 8mm thick on the right), each surrounded by a 10mm thick cladding plate. The spacing between the transverse diaphragms at the connection between the top-level main beam and the columns is reduced. The columns are connected to the top-level main beam, and the transverse diaphragm treatment for the remaining box-type thin-walled beams is the same as that for the main beam and the top-level main beam.

[0058] The main girder is 181230mm long and is a rectangular box girder structure with a cross-section consisting of two rectangles: one large (4800×2000mm) and one small (1000×940mm). The box girder contains several transverse diaphragms of varying spacing. Each diaphragm is encased in a 12mm thick cladding plate, which is composed of three ∅95×6 steel pipes forming an isosceles triangle. Angle steel is welded between the transverse diaphragms. Figure 6 As shown, Figure 6 This is a 3D model of the main beam cross-section. The top-level main beam is a thin-walled box girder structure with two different cross-sections, measuring 2400×1238mm and 1800×1234mm respectively. The structure is relatively simple, with thin-walled steel plates around the perimeter and reinforcing diaphragms at varying intervals in the middle. Figure 7 As shown, Figure 7 This is a cross-sectional view of the top-level main beam.

[0059] The structure provided in this embodiment is particularly suitable for large-span port bridge cranes, achieving an optimal balance between material usage and load-bearing capacity while ensuring rigidity.

[0060] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A mixed constraint wharf bridge crane three-span steel truss support optimization structure, characterized in that: The structure adopts a three-span continuous steel truss form, consisting of two side spans and one middle span. The truss height of each span gradually increases from the middle of the span towards the legs. The legs and the main truss are connected by a hybrid constraint method, including: hinged constraints in the longitudinal direction; elastic constraints in the transverse direction; and rigid constraints in the vertical direction. The bottom of each leg is provided with a foundation support. The foundation support adopts a composite structure, including: a ball joint support at the top; a damping rubber pad in the middle; and an anchor bolt group at the bottom. Stiffening ribs are provided at the connection nodes of each component in the structure.

2. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The three-span continuous steel truss has a side span to middle span ratio of 0.6-0.8:1 and a truss height variation gradient of 1:15-1:

20.

3. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The elastic constraint uses a disc spring assembly with a stiffness coefficient of 500-800 kN / mm and a pre-compression of 5-10 mm.

4. The optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints as described in claim 1, characterized in that: The spherical hinge support is designed to rotate at an angle of ±3°, and the spherical pad is made of a self-lubricating composite material.

5. The optimized structure for a three-span steel truss support of a dock bridge crane with hybrid constraints according to claim 1, characterized in that: The shock-absorbing rubber pad is a composite structure of natural rubber and lead core, with the diameter of the lead core being 1 / 3 to 1 / 2 of the thickness of the rubber pad.

6. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The stiffening ribs are arranged radially, and the thickness of the ribs is 0.8-1.2 times the thickness of the thicker plate of the adjacent component.

7. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The support leg has a trapezoidal cross-sectional shape, with the width of the upper base being 0.8-1.2 times the width of the lower base, and the height being 1 / 10-1 / 15 of the span.

8. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The connection node is constructed with T-shaped reinforcing ribs, the thickness of which is 1.2-1.5 times the thickness of the node plate, and drainage holes are provided at the node.

9. The hybrid restrained wharf bridge crane three-span steel truss support optimization structure according to claim 1, characterized in that: The steel truss is made of corrosion-resistant high-strength steel with a yield strength of not less than 355MPa and is coated with an epoxy resin anti-corrosion coating.

Images