Anti-fatigue ship deck strut

Abstract

The invention discloses an anti-fatigue ship deck strut which is an I-shaped strut composed of two panels and a web, the strut is arranged between an upper deck and a lower deck, a T-shaped profile is arranged below the decks, the upper end of the strut is connected with the panels of the T-shaped profile, the lower end of the strut is connected with the decks, and the panels of the T-shaped profile are connected with the webs. A web plate of the supporting column and a web plate of the T-shaped profile are oppositely arranged up and down, the upper ends and the lower ends of the two panels are both provided with bending parts which are bent in the direction away from the central axis of the supporting column, and the bending parts at the same ends of the two panels are arranged in a mirror symmetry mode. According to the anti-fatigue ship deck supporting column, the stress level value of a fatigue hot spot position can be effectively reduced through the supporting column with the folded angle type end portion, the specified fatigue life is easily achieved, and structural weight optimization can be achieved on the basis of calculation.

Description

Technical Field

[0001] The invention relates to the technical field of shipbuilding, and in particular to an anti-fatigue ship deck pillar. Background Art

[0002] In the hull structure design of the RoRo ship project, the end of the pillar is the hot spot stress area and is the key fatigue calculation point. Especially in the PCTC car RoRo ship project with a weak overall frame, the fatigue of the pillar end inside the PCTC cargo hold is difficult to calculate due to the weak lateral anti-roll structure, which becomes the most prominent difficulty in structural design and calculation.

[0003] To solve the fatigue problem at the ends of the pillars, considering the constraints such as vehicle loading rate and efficiency, the feasibility of implementing solutions such as overall strengthening of the hull's lateral strength or effectively reducing lateral acceleration and lateral load is relatively low. Therefore, studying and optimizing the structural form of the pillar ends has become one of the most critical solutions to solve the fatigue problem of ro-ro ships. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a fatigue-resistant ship deck pillar.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions: A fatigue-resistant ship deck pillar, the pillar is an I-shaped pillar composed of two panels and a web, the pillar is arranged between upper and lower decks, a T-shaped bar is arranged below the deck, the upper end of the pillar is connected to the panel of the T-shaped bar, the lower end of the pillar is connected to the deck, the web of the pillar and the web of the T-shaped bar are arranged opposite to each other up and down, the upper and lower ends of the two panels are provided with a bending portion bent in a direction away from the central axis of the pillar, and the bending portions at the same end of the two panels are arranged in a mirror-symmetrical manner.

[0006] Furthermore, internal horizontal supporting members are provided below the bent portion at the upper end of the support and above the bent portion at the lower end of the support, and the web of the support vertically penetrates the internal horizontal supporting members.

[0007] Furthermore, two internal vertical support members are provided at the upper and lower ends of the interior of the pillar, symmetrically arranged on both sides of the web and parallel to the web. The lower end of the upper internal vertical support member is connected to the internal horizontal support member at the upper part of the pillar, and the upper end of the lower internal vertical support member is connected to the internal horizontal support member at the lower part of the pillar.

[0008] Furthermore, the panel of the T-profile is provided with two middle sections of internal vertical support members which are symmetrically arranged on both sides of the web of the T-profile and parallel to the web of the T-profile. The middle sections of the internal vertical support members are arranged end to end opposite to the internal vertical support members in the opposite ends of the upper and lower pillars from top to bottom.

[0009] Furthermore, the thickness of the panel is a, the vertical distance between the bending line of the bending portion of the lower part of the pillar and the adjacent upper end surface of the deck is b, the vertical distance between the bending line of the bending portion of the upper part of the pillar and the lower end surface of the adjacent T-profile panel is b, the vertical distance between the end surface of the internal horizontal supporting member close to its adjacent bending line and the bending line is c, and the vertical distance between the inner sides of the two panels is d, wherein a<1 / 2d, a:b=1:3, c=15-50mm.

[0010] Furthermore, the bending angle β of the bending portion is 10°~15°.

[0011] Furthermore, the thickness of the internal horizontal supporting member in the vertical direction is t1, the thickness of the internal vertical supporting member and the internal vertical supporting member of the deck is t2, and t1=t2.

[0012] Furthermore, on the upper surface of the deck, a Z-direction high-strength steel plate embedded plate is laid around the pillars.

[0013] Furthermore, the Z-direction high-strength steel plate embedding plate is arranged coaxially with the pillar.

[0014] The anti-fatigue ship deck pillar of the present invention can effectively reduce the stress level value at the fatigue hot spot position by adopting the pillar with angled end form, easily achieve the specified fatigue life, and realize structural weight optimization based on calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a partial cross-sectional schematic diagram of the fatigue-resistant ship deck support according to the present invention in use in a ro-ro cargo hold.

[0016] Figure 2 for Figure 1 Enlarged schematic diagram of part A.

[0017] Figure 3 for Figure 2 AA direction view.

[0018] Figure 4 for Figure 3 Middle CC direction view.

[0019] Figure 5 for Figure 2 BB direction view.

[0020] Figure 6 for Figure 2 DD direction view.

[0021] Figure 7 This is a schematic diagram of the end node of the fatigue-resistant ship deck pillar according to the present invention.

[0022] Figure 8 This is a schematic diagram of the stress at the end of the fatigue-resistant ship deck pillar according to the present invention according to the FEM analysis.

[0023] Fig. 9 Schematic diagram of the traditional pillar end node.

[0024] Fig.10 Schematic diagram of stress at the end of a traditional support for FEM analysis.

[0025] Among them, 1-panel; 2-web; 3-deck; 4-T-profile panel; 5-T-profile web; 6-internal horizontal supporting member; 7-internal vertical supporting member; 8-Z-direction high-strength steel plate embedded plate, 101-bending part. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] like Figure 1-Figure 6 As shown, a fatigue-resistant ship deck pillar is an I-shaped pillar composed of two panels 1 and a web 2, the pillar is arranged between upper and lower decks 3, a T-shaped bar is arranged below the deck 3, the upper end of the pillar is connected to the T-shaped bar panel 4, the lower end of the pillar is connected to the deck 3, the web 2 of the pillar and the T-shaped bar web 5 are arranged opposite to each other up and down, the upper and lower ends of the two panels 1 are provided with a bending portion 101 bent away from the central axis of the pillar, and the bending portions 101 at the same end of the two panels 1 are arranged in mirror symmetry.

[0028] The main function of the pillar is to support the deck 3 structure. For ro-ro ships, the vehicle deck 3 mainly bears the vertical load (weight and vertical acceleration) and transverse load (weight and vertical acceleration) generated by the deck 3's own weight and the loaded cargo. Under the action of the transverse dynamic load, the pillar bears the load that tilts to the port or starboard, which manifests as tensile stress and compressive stress at the root of the pillar. The tensile stress and compressive stress form the stress range ∆σ for fatigue calculation. When the panel 1 of the pillar is vertical, the tensile and compressive stress it bears can only be transmitted in the direction of the vertical deck 3 plate. In this embodiment, the panel 1 at the end of the pillar is partially modified to have a folded angle, and a part of the vertical tensile and compressive stress can be decomposed into the thickened plate embedded in the deck 3, thereby effectively reducing the tensile and compressive stress range value ∆σ at the end of the panel 1. Finite element analysis has verified that this solution is effective in solving the fatigue problem at the end of the pillar.

[0029] Furthermore, an internal horizontal support member 6 is provided below the bent portion 101 at the upper end of the pillar and above the bent portion 101 at the lower end of the pillar, and the web 2 of the pillar vertically penetrates the internal horizontal support member 6 .

[0030] It is understandable that the purpose of setting the end of the pillar panel 1 in an angled form is mainly to reduce the tensile and compressive stresses at the weld between the panel 1 and the deck plate, thereby increasing the fatigue life of the connection position. The main principle is that the original stress between the panel and the deck can be decomposed into a part of horizontal stress. Since the assumed background is the vehicle deck area of ​​the ro-ro ship, in order to avoid affecting the operation of the vehicle, the restriction condition of a<1 / 2d is defined. Studies have found that within the range of the angle of 45 degrees, the greater the angle, the greater the force shared in the horizontal direction, and the longer the fatigue life of the connection between the pillar and the deck. The panel 1 of this structural connection form will inevitably generate lateral force at the angle. In order to support the resultant force at the angle position (the force synthesized by the angle panel and the vertical panel), an internal horizontal support member 6 needs to be added near the bending part of the two panels 1 of the pillar to support the force at the angle, so as to achieve effective support between the components.

[0031] Furthermore, the thickness of the panel 1 is a, the vertical distance between the bending line of the bending portion 101 at the lower part of the pillar and the upper end surface of the adjacent deck 3 is b, the vertical distance between the bending line of the bending portion 101 at the upper part of the pillar and the lower end surface of the adjacent T-profile panel 4 is b, the vertical distance between the end surface of the internal horizontal supporting member 6 close to its adjacent bending line and the bending line is c, and the vertical distance between the inner sides of the two panels 1 is d, wherein a<1 / 2d, a:b=1:3, and c=15-50mm.

[0032] Furthermore, the bending angle β of the bending portion 101 is 10°~15°.

[0033] In some embodiments, the pillars of the present invention are applied to the cargo holds of car roll-on / roll-off ships, which are used for loading cars. Although the fatigue problem of the ends of the pillars is solved by setting the ends of the pillar panel 1 to an angled form, if only the angled form of the end face of the panel 1 is improved, it is found through analysis that the bending angle needs to be no less than 45° to ensure the stability of the pillar. However, if the angle is too large, it will inevitably affect the use of the cargo hold and the loading of the car. In order to solve this technical problem, the bending angle of the bending portion 101 is controlled to 10°~15° by specially setting the above-mentioned structural dimensions to avoid the width of the bottom of the pillar affecting the loading of the vehicle.

[0034] Furthermore, two internal vertical support members 7 are provided at the upper and lower ends of the interior of the pillar, which are symmetrically arranged on both sides of the web 2 and parallel to the web 2. The lower end of the upper internal vertical support member 7 is connected to the internal horizontal support member 6 at the upper part of the pillar, and the upper end of the lower internal vertical support member 7 is connected to the internal horizontal support member 6 at the lower part of the pillar.

[0035] In order to further reduce the tensile and compressive stresses at the weld between the panel 1 and the deck plate, internal vertical support members 7 are added at 150 mm from the web on both sides of the pillar. The main principle is to increase the connection area at the bottom of the pillar, which can effectively reduce the stress level at the end of the pillar and improve the fatigue life of the welding position. If the fatigue life is further improved, brackets can be added in the direction where the ends of the pillars bear tensile and compressive stresses.

[0036] It can be understood that in order to ensure the stability of the pillar when the bending angle of the end of the pillar panel 1 is 10°~15°, internal vertical support members 7 are set in the bending sections at both ends of the pillar panel 1 to increase the connection area between the pillar and the deck 3 and the T-profile panel 41.

[0037] Furthermore, two internal vertical support members 7 are symmetrically arranged on both sides of the T-profile web 5 and parallel to the T-profile web 5 on the T-profile panel 4. The internal vertical support members 7 are arranged opposite to the internal vertical support members 7 in the opposite ends of the upper and lower pillars from top to bottom.

[0038] It is understandable that adding an internal vertical support member 7 between the T-profile panel 4 and the deck 3 can help the deck 3 and the T-profile panel 4 to withstand the force from the pillars.

[0039] Furthermore, the thickness of the internal horizontal supporting member 6 in the vertical direction is t1, and the thickness of the internal vertical supporting member and the internal vertical supporting member of the deck 3 is t2, and t1=t2.

[0040] Furthermore, on the upper surface of the deck 3, a Z-direction high-strength steel plate embedded plate 8 is laid around the pillars.

[0041] Furthermore, the Z-direction high-strength steel plate embedding plate 8 is arranged coaxially with the pillar.

[0042] Due to the large tensile and compressive stresses at the ends of the car roll-on / roll-off ship's pillars, the ends of the pillar panel 1 are modified into angled pillars. On this basis, the force along the horizontal direction is increased, and the force direction becomes complicated. In order to reduce the risk of laminar tearing, Z-direction high-strength steel embedded plates are used to improve the ability to resist fatigue damage.

[0043] like Figure 7 and Figure 8 As shown in FIG. 1 , the compressive stress at the connection position between the end of the angled support panel 1 and the deck 3 is -99.05Mpa and -101Mpa; Fig. 9 and Fig.10 As shown in the figure below, the compressive stress at the connection position between the end of the vertical panel 1 type pillar panel 1 and the deck 3 plate is -398.84Mpa and -160.28Mpa. It can be seen that under the same load, the compressive stress levels are quite different, and the tensile stress results are consistent.

[0044] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A fatigue-resistant ship deck pillar, the pillar is an I-shaped pillar composed of two panels and a web, the pillar is arranged between upper and lower decks, a T-shaped bar is arranged below the deck, the upper end of the pillar is connected to the panel of the T-shaped bar, the lower end of the pillar is connected to the deck, the web of the pillar and the web of the T-shaped bar are arranged opposite to each other in the upper and lower directions, characterized in that: The upper and lower ends of the two panels are both provided with bending parts bent in a direction away from the central axis of the pillar, and the bending parts at the same end of the two panels are arranged in mirror symmetry.

2. The fatigue-resistant ship deck pillar according to claim 1, characterized in that: Internal horizontal supporting members are provided below the bent portion at the upper end of the support and above the bent portion at the lower end of the support, and the web of the support vertically penetrates the internal horizontal supporting members.

3. The fatigue-resistant ship deck pillar according to claim 2, characterized in that: Two internal vertical support members are provided at the upper and lower ends of the interior of the pillar, which are symmetrically arranged on both sides of the web and parallel to the web. The lower end of the upper internal vertical support member is connected to the internal horizontal support member at the upper part of the pillar, and the upper end of the lower internal vertical support member is connected to the internal horizontal support member at the lower part of the pillar.

4. The fatigue-resistant ship deck pillar according to claim 3, characterized in that: The panel of the T-profile is provided with two middle sections of internal vertical support members which are symmetrically arranged on both sides of the web of the T-profile and parallel to the web of the T-profile. The middle sections of the internal vertical support members are arranged end to end opposite to the internal vertical support members in the opposite ends of the upper and lower pillars from top to bottom.

5. The fatigue-resistant ship deck pillar according to claim 4, characterized in that: The thickness of the panel plate is a, the vertical distance between the bending line of the bending part of the lower part of the pillar and the adjacent upper end surface of the deck is b, the vertical distance between the bending line of the bending part of the upper part of the pillar and the lower end surface of the adjacent T-profile panel is b, the vertical distance between the end surface of the internal horizontal supporting member close to its adjacent bending line and the bending line is c, and the vertical distance between the inner sides of the two panels is d, wherein a<1 / 2d, a:b=1:3, c=15-50mm.

6. The fatigue-resistant ship deck pillar according to claim 5, characterized in that: The bending angle β of the bending portion is 10°~15°.

7. The fatigue-resistant ship deck pillar according to claim 6, characterized in that: The thickness of the internal horizontal supporting member in the vertical direction is t1, and the thickness of the internal vertical supporting member and the internal vertical supporting member of the deck is t2, t1=t2.

8. The fatigue-resistant ship deck pillar according to any one of claims 1 to 7, characterized in that: The fatigue-resistant ship deck pillar is characterized in that a Z-direction high-strength steel plate embedded plate is laid around the pillar on the upper plate surface of the deck.

9. The fatigue-resistant ship deck pillar according to claim 8, characterized in that: The Z-direction high-strength steel plate embedding plate is arranged coaxially with the support column.

Images