JPS6215183Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a container roof plate.

The roof plate of a container must be able to withstand the load of workers who ride on it when loading, unloading or cleaning the container. For this reason, a corrugated panel 1 as shown in FIG. 1 has generally been used for the roof of a container. In addition,
The corrugated panel 1 has peaks 2 and troughs 3 having a substantially trapezoidal cross-sectional shape arranged alternately, and these peaks 2 and troughs 3 are provided in parallel over the entire length of the panel 1. This is a so-called corrugated steel sheet. By the way, when the weight W of the worker acts on the central part of the corrugated panel 1 as shown in FIG. 2, the maximum bending moment M generated in the corrugated panel 1 is as follows: M=Wl/4. Here, if the section modulus of the loaded part is Z, then
The maximum bending stress σ at the loaded part can be expressed as σ=M/Z. If the value of σ is within the strength of the material used for the corrugate panel 1, the strength of the corrugate panel 1 is considered to be sufficient. however,
As a prerequisite for this, the buckling strength of the corrugated surface must be guaranteed.

The buckling strength of the corrugated surface can conveniently be calculated as elastic buckling due to a unidirectional compressive load, and can be expressed as σ _cr =k·π ² E/12(1−ν ² )(t/b) ² .

Here, σ _cr : Buckling stress E: Longitudinal elastic modulus of corrugated panel 1 ν: Poisson's ratio of corrugated panel 1 t: Thickness of corrugated panel 1 b: Width dimension of peaks 2 and troughs 3 of corrugated panel 1 k: Buckling stress coefficient.

If we rewrite the above equation, we get σ _cr = f[(t/b) ² ], so the buckling stress σ _cr is
It can be seen that it is proportional to the square of the ratio between the plate thickness t and the width b of the peak portion 2 or the valley portion 3. Here, if the thickness t of the corrugated panel 1 is constant, the buckling strength σ _cr is determined by the width b of the peaks 2 or troughs 3, so the width b
The maximum dimension was limited by itself, and it was not possible to make the width as large as desired. Therefore, a large number of peaks 2 and valleys 3 are required in the corrugated panel 1, which is disadvantageous in terms of material cost.

The present invention was devised to correct the above-mentioned defects, and it is possible to prevent sufficient buckling even if the width of the peaks or valleys of the corrugated panel is made wider or the thickness of the corrugated panel is made thinner. The purpose of the present invention is to provide a container roof sheet that provides strength.

An embodiment of the present invention will be described below with reference to FIG.

As shown in Fig. 3, the corrugated panel 1, which is a corrugated steel plate as explained in Figs. A concave ivy-shaped protrusion 4 is pressed. This protrusion 4 has peaks 2 and troughs 3.
are provided in the center of each. Further, the dimensions of the protrusion 4 are much smaller than the vertical width c of the peaks 2 and troughs 3.

Since the roof plate of the container is constructed as described above, the width dimension b of the peak portion 2 or the valley portion 3 is apparently b/2. Therefore, the buckling strength of the corrugated panel increases. Therefore, even if the width dimension b of the peak portions 2 or the valley portions 3 is increased, the corrugated panel 1 will not buckle. Further, even if the thickness t of the corrugated panel 1 is made thinner, buckling will not occur in the same way.

Although one embodiment of the present invention has been described above, the present invention is not limited to the structure shown in the above embodiment and can be modified in various ways. For example, the protrusion 4 may be pressed into a convex shape as shown in FIG.
Further, as shown in FIGS. 5 and 6, two protrusions 4 may be provided in each of the peaks 2 and troughs 3. In this case, the apparent width of the peaks 2 and troughs 3 is b/3, and the buckling strength further increases. Also, the protrusion 4 is 3
Of course, more than one book may be provided.

As mentioned above, the present invention has concave or convex protrusions pressed along the longitudinal direction of the peaks or valleys of the corrugated panel, so it has higher buckling strength than conventional corrugated panels. increase Therefore, it is possible to reduce the thickness of the corrugated panel while maintaining the same buckling strength as the conventional corrugated panel, and thus it is possible to reduce the material cost of the corrugated panel.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional corrugated panel.
Fig. 2 is an explanatory diagram for explaining the state when a load is applied to the same corrugated panel as above, Fig. 3 is a cross-sectional view of the corrugated panel showing an embodiment of the present invention, and Figs. 4 to 6 are It is a cross-sectional view of a corrugated panel showing a modification of the present invention. In addition, in the symbols used in the drawings, 1...corrugate panel, 2...peak, 3...trough, 4...
...It is a ridge.

Claims (1)

[Scope of utility model registration request] A container roof plate made of a corrugated panel in which peaks and valleys having a substantially trapezoidal cross-sectional shape are arranged alternately, and the peaks and valleys are parallel to each other over the entire length of the panel. In,
A roof board for a container, characterized in that concave or convex protrusions are pressed along the longitudinal direction of the peaks or valleys of the corrugated panel.