JPH0711641A - Anchoring - Google Patents

Abstract

PURPOSE:To provide an economical anchoring which disperses the adhesion stress of an anchor and the surrounding ground and does not bring about the spot suffering from a large concentrated stress. CONSTITUTION:A plurality of tension members are integrated, shifting the respective positions of peeled-off parts 2 of the front end of a covered steel cable, by use of the tension members 1 in the peeled-off state. This group of tension members is inserted in an anchor hole, letting the peeled-off part 2 position at the front end and the peeled-off part is fixed in the hole by a solidifier. Then a tension is forced at the tail end of the peeled-off part 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor construction method.

[0002]

2. Description of the Related Art A wire rod in which the front end side of a coated steel wire is peeled off is used, and a plurality of wire rods are assembled with the positions of the peeling portions aligned, and this wire rod group is anchored with the peeling portion side as the tip. There is an anchoring method in which the peeling portion is fixed in the hole by a solidifying agent and a tension is applied to the tail end side of the covering portion.

[0003]

[Problems to be Solved by the Invention] The conventional anchor construction method described above has the following problems.

<A> As shown in FIG. 4, when a tension P is applied to the tension member a, the stress is transmitted to the anchor body. Then, since the peeling portion b of the tension material a is constrained by the grout c around the periphery, the displacement amount of the tension material peeling portion b is maximum at the fixing base end (the hole mouth side of the peeling portion) and is directed toward the hole bottom. Decrease.
The distribution of stress (left in the figure) is also the same, and it is considered that the stress is transmitted up to the range where the tension force P introduced into the tensile material a and the adhesive force between the tensile material a and the grout c are balanced. Therefore, when the peeled portion b is relatively long, it is possible that no stress is applied to the bottom of the hole. In addition, the stress distribution of the anchor body (right in the figure) also has a distribution concentrated near the anchorage base end, and the stress transmitted from the anchor body to the surrounding ground is considered to be the same distribution.

<B> The tensile force acting on the tensile member a is opposed by the frictional force between the ground and the anchor body. However, since the stress distribution is concentrated on a part as described above, a larger tensile force acts, and when the stress becomes larger than the frictional resistance, the stress distribution moves to the hole bottom side. (I to III in the same figure) It is considered that the ultimate strength of the anchor body is when the area of the distribution type of the frictional stress becomes maximum. From a microscopic point of view, the frictional resistance on the fixing base end side is in a yielding state, which means that the anchor body is being destroyed.

<C> For this reason, in the case where the conventional anchor body has a small ground frictional resistance force, there is a case where the anchor body strength cannot be obtained even if the fixing length is increased to increase the overall frictional resistance. There was a problem. <D> When a plurality of tensile members a are further arranged and all the peeling portions b are aligned, the apparent adhesion area is reduced, and the destruction of the anchor body causes the anchor to progress. In some cases, the body was stretched and the yield strength was not stable.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and is an economical method that disperses the adhesion stress between the anchor body and the surrounding ground and does not generate a large stress concentration point. The purpose is to provide an anchor construction method.

[0008]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the anchoring method of the present invention uses a tensile member in which the tip side of a coated steel wire is peeled off, and a plurality of tensile members are used. Are assembled by shifting the position of the peeling part, and the tensile material group is inserted into the anchor hole with the peeling part side as the tip, and the peeling part is fixed in the hole by the solidifying agent, and the tail end side of the covering part. It is characterized by giving tension to the person.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. <A> Member to be used The tensile member 1 in a state where the tip side of the coated steel wire is peeled off is used. And in particular, the tensile member 1 used in the construction method of the present invention is
Several kinds of tensile members 1 group having different lengths of the peeled portion 2, that is, the position of the exposed portion of the steel wire are prepared.

<B> Assembly of Tensile Material 1 A plurality of tensile materials 1 are assembled and assembled to manufacture an anchor body. In this case, in particular, the peeling portions 2 of the tensile member 1 are displaced in position and assembled. Therefore, the tip of the peeling portion 2 of the second tensile member 1 is located at the boundary between the covering portion 3 and the peeling portion 2 of the most up-to-date tensile member 1 which is located closest to the bottom of the hole. The tip of the peeling portion 2 of the third tension member 1 is located at the boundary between the covering portion 3 and the peeling portion 2.

In this way, the periphery of the covering portion 3 is sequentially covered with the peeling portion 2
Is configured so as to be surrounded by. Further, the group of tension members 1 is surrounded by a sheath 4 to protect the peeling portion 2 from permeation of groundwater or the like. The sheath 4 is a tubular body made of a flexible and water-impermeable material having a predetermined tensile strength.

<C> Insertion into the anchor hole The group of tension members 1 thus constructed is inserted into the anchor hole with the peeling portion 2 side as the tip. The hole is filled with the solidifying agent after the insertion or before the insertion. The solidifying agent is also filled inside the sheath 4. Therefore, a dedicated pipe for supplying the solidifying agent may be provided in the sheath 4. Thus, after a certain period of time, the peeling portion 2 of the tensile member 1 is fixed in the hole by the solidifying agent, but since the peeling portion 2 is located around the covering portion 3, the peeling portion as in the prior art is concentrated. Unlike the structure in which the solidifying agent is present, the solidifying agent can sufficiently rotate around the peeling portion 2 and be fixed securely.

<D> When tension solidification is completed and constant strength can be obtained,
A jack is arranged on the tail end side of the covering portion 3 to apply tension to complete the construction.

[0014]

Since the anchor construction method of the present invention is as described above, the following effects can be obtained. <A> The fixing portion where the adhesiveness can be obtained by the solidifying agent, that is, the peeling portion 2 of the tensile member 1 is not concentrated in one place but is dispersed in a plurality of places. Therefore, the adhesion stress from the tensile member 1 to the anchor body and the ground is dispersed in a small amount as shown in FIG. 3, and does not act largely in one place unlike the conventional case.
Therefore, it is possible to construct an anchor having a large proof stress even on the ground having a small frictional resistance.

<B> Further, since the stress corresponding to the adhesion force of the ground acts in a dispersed manner, the frictional resistance between the anchor body and the ground does not yield, the displacement of the tensile member with respect to the load is small, and the yield strength is stable. It is highly likely.

[Brief description of drawings]

FIG. 1 is an explanatory view of a tensile member used in the method of the present invention.

[Fig. 2] Illustration of the construction status

FIG. 3 is an explanatory diagram of a stress distribution state.

FIG. 4 is an explanatory diagram of a stress distribution state in the conventional construction method.

Claims (2)

[Claims] 1. A tensile member in which the tip side of a coated steel wire is peeled off is used, and a plurality of tensile members are assembled by shifting the position of the peeling part, and this tensile material group is tipped on the peeling part side. Then, insert it into the anchor hole, fix the peeling part in the hole with a solidifying agent, and apply tension to the tail end side of the covering part. 2. A state-of-the-art tensile member in which a plurality of tensile members are assembled by shifting the positions of the peeling parts, using a tensile member in which the tip side of the coated steel wire is peeled off, The tip of the peeling portion of the second tensile material is positioned at the boundary between the covering portion and the peeling portion of the material, and the third peeling portion of the tensile material is located at the boundary between the covering portion and the peeling portion of the second tensile material. The tensile member group is inserted into the anchor hole with the peeling part side as the tip, and the peeling part is fixed in the hole by the solidifying agent, and the tension force is applied to the tail end side of the covering part. Anchor construction method