JPH0367861B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to tendons used for prestressed structures, ground anchors, and the like.

More specifically, the present invention relates to a case where a fiber-reinforced resin composite arranged and bundled in the longitudinal direction is used as a tendon material.

[Conventional technology and problems]

Traditionally, the tension materials used in prestressed structures and ground anchors include steel wire for prestressed concrete, steel bars, and stranded wire (hereinafter referred to as PC steel wire).
These PC steel wires, PC steel bars, and PC stranded wires are widely used.
Stranded wire has the risk of rusting, and once rust develops and corrosion progresses, there is a risk of serious structural problems such as reduction or disappearance of prestress. Attempts are being made to use fiber-reinforced resin composites reinforced with continuous filaments arranged and bundled in the longitudinal direction.

Various methods have been proposed for tensioning and fixing this fiber-reinforced resin composite tendon, but all of them involve tensioning and fixing a single fiber-reinforced resin composite tendon. The capacity was small and insufficient for practical tension capacity.

The reason for this is that tendons made of fiber-reinforced resin composites are often manufactured by the pultrusion method, but tendons made of fiber-reinforced resin composites with a large cross-sectional area tend to have voids inside, and are also heated. There are manufacturing problems such as difficulty in curing, and fiber-reinforced resin composite tendons with large cross-sectional areas have a small ratio of surface area to cross-sectional area, making it difficult to cure conventional tension materials.
The fixing method has a problem in that the high tensile strength of the fiber-reinforced resin composite tension material cannot be fully utilized.

[Means for solving problems]

Therefore, as a result of intensive studies to solve these problems, the present inventors have found that the above problems can be solved by using a tension material in which a plurality of fiber reinforced resin composites are integrally fixed using a specific method. We have arrived at the heading Invention.

That is, an object of the present invention is to fully utilize the inherent strength of a fiber-reinforced resin composite reinforced with continuous filaments arranged and bundled in the longitudinal direction, which is a tendon material used in prestressed structures and ground anchors, and to provide a large-capacity material. The purpose is to provide tendons.

The object is a fiber-reinforced resin composite tendon made by bundling and integrating a plurality of fiber-reinforced resin composites reinforced with continuous filaments, and at least one of the fiber-reinforced resin composites constituting the tendon. This can be easily achieved by using a tendon made of a fiber-reinforced resin composite, which is characterized in that the end portions of the fiber-reinforced resin composite are expanded through spacers, and then the expanded portions are impregnated with resin and cured to be integrally fixed.

The present invention will be explained in more detail below.

Examples of the continuous long fibers used in the present invention include carbon fibers, aramid fibers, and glass fibers, but it is preferable to use carbon fibers or aramid fibers from the viewpoint of physical properties such as tensile strength.

A fiber-reinforced resin composite using such continuous long fibers as a reinforcing material can be easily manufactured by using a thermosetting resin such as an epoxy resin or an unsaturated polyester resin as a matrix resin and using a conventional method, for example, a pultrusion method. I can do it.

The tension material of the present invention is produced by bundling a plurality of the above fiber-reinforced resin composites in parallel, expanding at least one end via a spacer, and impregnating and hardening the expanded part with an epoxy resin or the like. It is important to fix it in one piece.

The spacer to be used is not particularly limited as long as it can maintain the expanded shape at the end of the composite, for example, a plate-shaped spacer with the same number of holes as the number of bundled pieces expanded at the end. This is done by pushing a wedge-shaped body in the direction of the fiber axis using a product, a plurality of them, or a plurality of them bundled together.

In addition, although any one end of the tendon material of the present invention may be fixed integrally as described above, both ends may be fixed in the same manner as necessary.

Furthermore, to explain the present invention more specifically using drawings, the fiber-reinforced resin composite tendon of the present invention is produced by bundling a plurality of fiber-reinforced resin composite tendons 1 as shown in FIG. Tensile material 1 made of fiber reinforced resin composite is inserted through spacer 2 and spacer 3 (having through hole 4 as shown in FIGS.
It has a widened shape at the end. In this example, a case of five is shown, but the number can be arbitrary. Spacers are shown in Figures 4 and 5.
It can also have a shape as shown in the figure.

Since the fiber-reinforced resin composite tension material of the present invention has a shape that expands at the end of the fiber-reinforced resin composite tension material 1 via the spacers 2 and 3, this portion is hardened with resin or the like. As a result, when embedded in concrete or mortar, it exhibits an anchor effect and can obtain high pull-out strength.

In addition, when the fiber-reinforced resin composite tension material of the present invention is used as a tension material in a ground anchor, as shown in Figure 6, the fiber-reinforced resin composite has excellent corrosion resistance, so it can be used permanently. (5 is the anchor head, 6 is the anchor body).

〔Effect of the invention〕

As explained above, in the fiber-reinforced resin composite tendon material of the present invention, a plurality of fiber-reinforced resin composite tendon materials are bundled, the ends are spread through spacers, and the spread portions are hardened with resin. This allows it to be shaped into any shape, and this part can be used to easily perform tensioning and fixing work, and the original strength of the fiber-reinforced resin composite reinforced by continuous filaments arranged and focused in the longitudinal direction is maintained. It can be fully utilized and can be used in cases where a large tension capacity is required.

Furthermore, by using the fiber-reinforced resin composite tendon material of the present invention in the fixed end portion of the tendon material used in prestressed structures and ground anchors, the fixed end portion can be made sufficiently safe against tension loads.

[Brief explanation of drawings]

Figure 1 shows fiber-reinforced resin composite tendons and spacers, Figure 2 shows spacers with through holes (small),
Figure 3 shows a spacer with through holes (large), Figures 4 and 5 show other shapes of spacers with through holes, and Figure 6 shows an example of the tension material made of fiber reinforced resin composite of the present invention. ground anchor). 1... Tension material made of fiber reinforced resin composite, 2... Spacer with through hole (small), 3... Spacer with through hole (large), 4... Through hole, 5... Anchor head, 6... Anchor body.

Claims (1)

[Claims] 1 A tendon material made of a fiber-reinforced resin composite made by bundling and integrating a plurality of fiber-reinforced resin composites reinforced with continuous long fibers, in which at least one end of each fiber-reinforced resin composite constituting the tension material is 1. A tendon made of a fiber-reinforced resin composite, characterized in that it is expanded through a spacer and then fixed integrally by impregnating the expanded portion with resin and curing it.