JPH02490B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a dam equipped with a raised relief weir.

(Prior Art) Raising concrete dams has recently been reconsidered because it can increase the amount of water stored. The simplest means of raising the height of this high dam is to use an undulating weir made of a flexible material, for example rubberized cloth.

Generally speaking, a high dam has its foundation 1 as shown in Figure 1.
and seawall 2 (hobu). To install the undulating weir made of flexible material on this, first the foundation 1,
Anchor bolts 3 are driven into the seawall 2. When the main body carpet 4 forming the covering (bag-like body), that is, the undulating weir is fixed on the upstream and downstream sides with the anchor bolts 3 which have been driven, the main body carpet is attached and the undulating weir is formed. Note that in Figure 1, means for injecting and draining fluid (e.g., air, water, etc.), which is a pressure medium for expanding the envelope, are omitted. 48-3458).

(Problem to be Solved by the Invention) However, unlike the conventional case where the main body carpet 4 is installed horizontally in the undulating weir, how does it relate to the curved part of the dam foundation 1 in the part A in Fig. 1? The problem was whether to attach it.

As shown in Figure 3, conventional undulating weirs have horizontal foundations, so both the foundation and revetment parts can be bonded together without cutting the strength members of flexible membrane materials, especially the strength members in the flow direction. , it is possible to produce membrane materials for undulating weirs.

This method eliminates the need to create seams (bonds) in the membrane material in the flow direction, where the principal stress is applied.
This makes it possible to provide a membrane material with high strength and reliability.

Generally, the width of the flexible membrane material is limited, and the envelope (bag-like body) is manufactured by pasting these membrane materials together. This seam is 7 in FIG. 2. Further, the strength member of this flexible membrane material is a woven fabric such as a nylon fabric, and the direction of the threads thereof is generally parallel to and perpendicular to the seam 7 of the flexible membrane material. The direction parallel to this seam 7 is the flow direction, and the stress in the flow direction of the weir envelope is taken care of.
The direction perpendicular to this is responsible for the axial stress of the weir envelope.

Note that as described above, the stress in the flow direction is the principal stress.

(Means for solving the problem) As a result of examining the relationship with the basic curve, the present inventor found that it is better to make the shape of the weir more comfortable when it is collapsed than when it is expanded. Recognizing that this is a necessary condition, the present invention was completed.

That is, the present invention provides an envelope made of a flexible membrane material attached to a dam, and injecting fluid into the interior of the envelope to expand and raise the envelope, and expel fluid from the interior of the envelope to cause the envelope to contract and fall down. In order to ensure that the attachment shape of the envelope corresponds to the shape of the joining curve between the dam's revetment and the curved foundation when it is toppled, a flexible membrane material that will correspond to the joining curve when it is toppled is attached. This is done by pasting together the membrane material of the seawall part with the threads in the flow direction cut and the membrane material of the foundation part where the threads in the flow direction are not cut. Equipped with a raised relief weir characterized in that the length to the curve that corresponds to the joint curve when it is collapsed is equal to the length from the membrane material fixing point of the seawall to the joint curve corresponding to the above. It's a dam.

The present invention will be explained in detail below.

The present invention provides a method for installing a flexible membrane weir on a concrete dam with a curved foundation so that the weir can completely undulate on the concrete dam. This is a flexible membrane weir.

That is, as shown in FIG. 2, which is a detailed view of section A in FIG. That is, the mounting shape of the main body carpet 4 must be such that the curve 6 of the corner portion of the main body carpet 4 and the curve 5 of the dam foundation substantially coincide with each other when the main body carpet 4 is collapsed.

In order to achieve this shape, the carpet should be attached in the direction parallel to the flow in both the bank protection and the foundation parts, and the intersection line should be attached as shown in Figure 2.
The threads in the flow direction of the seawall are cut, and the carpet for the seawall part with the threads in the flow direction cut is pasted at the seam of this intersection line, and the carpet for the foundation part where the threads in the flow direction are not cut as before. Must match.

If the threads in the flow direction of the revetment section are not cut and the shape is not matched to the curve of the dam foundation at the seam of this intersection line, it will be It becomes sagging and protrudes.

The length from the fixed point of the carpet of the revetment part (a certain fixed point) to the curve 6 of the corner section is approximately the same as the length from the carpet fixed point of the dam revetment to the curve 5 of the dam foundation, which corresponds to the above. This is necessary to ensure that the envelope does not lift up during lodging.

In the case of a undulating weir made of membrane material with a curved foundation like this, in order to prevent sagging when it collapses, it is necessary to cut the threads in the flow direction at some point and attach the membrane materials of the foundation and revetment parts. However, it is better to place this pasted part away from the foundation where the tension is greatest, so it is pasted at the joint between the seawall and the foundation.

(Function) This shape has some problems when expanded (expanded shape), but it is unavoidable in order to reduce the resistance when water overflows during lodging.

(Effects of the Invention) In the present invention as described above, the undulating weir in the collapsed state does not serve as a protection against running water, and no abnormal force is applied to the undulating weir in the collapsed state.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of a dam equipped with a raised undulating weir according to the present invention, and FIG. 2 is an enlarged perspective view of a portion A circled in FIG. 1. In addition, FIG. 3 is a perspective view of a conventional general undulating weir. 1...Foundation of the dam, 2...Dam protection (hobu),
3... Anchor bolt, 4... Covering (body carpet), 5... Curve of dam foundation, 6... Curve, 7
...The seam of flexible membrane.

Claims (1)

[Claims] 1 In a case where an envelope made of a flexible membrane material is attached to a dam and a fluid is injected into the interior of the envelope to cause it to expand and stand up, and the fluid is discharged from the interior of the envelope to cause it to contract and fall down. In order to ensure that the attachment shape of the cover matches the shape of the joining curve between the dam's revetment and the curved foundation when it is toppled, the flexible membrane material that will be attached to the part that corresponds to the joining curve when it is toppled is attached using threads in the flow direction. This is done by pasting together the membrane material of the seawall part that has been cut and the membrane material of the foundation part where the threads in the flow direction are not cut. The length to the curve, which is the part corresponding to the curve, is
A dam equipped with a raised undulating weir, characterized in that the length is equal to the length from the membrane material fixing point to the joining curve of the seawall corresponding to the above.