JPH0573870B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a snow melting device for the lower part of a transmission line tower, etc.
In particular, it relates to a snow melting device at the bottom of a steel tower that uses heat pipes and underground heat.

[Prior art and its problems] Due to snow accumulation, a downward force called a settling force and a horizontal force called a moving pressure act on the lower part of a steel tower. The settling force will be explained with reference to FIG.

There is a large amount of snow 6 in a place where there are horizontal or diagonal beams (structures), and when the snow 6 becomes compacted (settling), the beam becomes an obstacle and the snow layer becomes curved as shown in the diagram. As a result, a very large downward force is applied to the beam. This force is called settling force, and in the case of a horizontal beam, it reaches 3 to 4 tons per meter of snow when the snow is 5 meters deep. For this reason, the strength of steel towers in areas with heavy snowfall is increased by making the lowest horizontal member higher than the snow depth and also making the diagonal reinforcing members thicker.

Next, the moving pressure will be explained with reference to FIG. The snow pile 6 on the slope moves downward along the slope as time passes and the temperature rises, and if there is an obstacle such as the lower part of a steel tower on the way, a very large force acts on the snow pile 6 in the moving direction. For this reason, the lower part of the steel tower in areas with heavy snowfall,
In addition to thickening the members, the underground foundation has also become stronger.

In this way, steel towers in areas with heavy snowfall have increased strength to withstand the settling force and moving pressure exerted on the bottom by snow accumulation, and their construction costs are higher than those in snow-free areas. . Furthermore, if snowfall exceeds the design value, damage to components or even tilting of the steel tower may occur, so the design snowfall amount needs to be large enough to take safety into consideration.

[Object of the Invention] An object of the present invention is to provide a tower lower snow melting device that eliminates the drawbacks of the prior art described above and can take measures against snow damage in a simple manner.

[Summary of the Invention] The gist of the present invention is, first, to melt snow around members at the bottom of the steel tower using underground heat using heat pipes, and second, to dissipate heat between the members at the bottom of the steel tower and the heat pipe. By thermally separating the parts from each other, it is possible to protect the members from damage caused by snow accumulation with a small amount of heat.

[Embodiments of the Invention] To explain with reference to the drawings, the lower part of the steel tower shown in FIG. There, a heat pipe 1 is buried in the ground 8 near the main landing gear 5 with one end as a heat collecting part, and the other end as a heat dissipating part along the diagonal member 4 and in contact with the upper side of the diagonal member 4. arranged in the form.

In such a configuration, when the temperature around the steel tower becomes lower than the temperature underground in winter, the heat pipe 1 uses its heat transfer action to remove heat from the underground.
Heat dissipates above ground. Even if part or all of the above-ground part of the heat pipe 1 is covered with snow 6, the heat pipe 1 continues to radiate heat in the above-ground part.
A part of this heat is directly radiated to the snow 6, but most of it is transferred from the heat pipe 1 to the diagonal member 4.
Heat is radiated from the diagonal members 4 into the snow 6. As a result, the snow 6 around the diagonal member 4 is melted, and a snow cavity 7 is formed as shown in FIG. 2A. As the snow 6 settles or moves, an oblong cavity 7' as shown in FIG.

In this case, the heat of the diagonal members 4 is not only transmitted to the surrounding snowpack 6, but also to other members connected to the diagonal members 4, so some of the heat brought from underground , or much of it is consumed for purposes other than its intended purpose.

3 and 4 show an example of the present invention, which is designed to eliminate heat transfer to the diagonal members 4 and effectively utilize underground heat.

This example differs from the previous example in that the heat dissipation part of the heat pipe 1 attached to the diagonal material 4 does not come into contact with the diagonal material 4, but has an appropriate distance between it and the diagonal material 4. In other words, they are installed in a thermally isolated manner. As a method for such thermal isolation, it is possible to continuously or intermittently interpose a spacer with poor thermal conductivity.

By installing the heat pipe 1 in this manner, almost no heat from the heat pipe 1 is transmitted to the diagonal member 4, and is radiated directly to the snowfall 6. Therefore, the accumulated snow 6 around the heat pipe 1 is effectively melted, creating a large cavity 7 as shown in FIG. 4A. As the snow 6 settles or moves, the snow 6 melted by the heat pipe 1 becomes unidirectional, so as shown in FIG. As a result, almost no load from the snow 6 is applied to the diagonal members 4.

In the case of the present invention, the heat pipe 1 does not need to be a single piece, and the underground part or the above-ground part may be branched into a plurality of pipes. Also, in the previous example, soil heat was used as the heat source, but if surface water is available, it can also be used as the heat source. Objects to be protected from damage caused by snow accumulation include not only power transmission line towers, but also ski lifts and other towers.

[Effects of the Invention] According to the present invention, a heat pipe using underground heat as a heat source is placed along a member of the lower part of the steel tower to melt surrounding snow, so that no load due to snow is applied to the member, for example, a diagonal member. Since it has been made possible to eliminate or significantly reduce the load due to snow accumulation as the strength required for the member, there is an effect that the accounting burden on the member can be significantly reduced.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing an example of a snow melting device, Fig. 2 is an explanatory diagram showing its operation and effects, Fig. 3 is an explanatory diagram showing an embodiment of the device according to the present invention, and Fig. 4 is its operation. FIG. 5 is an explanatory diagram of the settling force due to snow accumulation, and FIG. 6 is an explanatory diagram of moving pressure due to snow accumulation. 1: heat pipe, 2: steel tower main column material, 3: steel tower horizontal material, 4: steel tower diagonal material, 5: steel tower main leg, 6: snowfall, 7, 7': hollow.

Claims (1)

[Claims] 1 One end of the heat pipe is buried in the ground near the steel tower, and the other end of the heat pipe is thermally separated from the member at the bottom of the tower where the load is applied due to snow accumulation. A snow melting device at the bottom of a steel tower.