JPH0749651B2 - Steel parent pile for prestress pile - Google Patents

Description

TECHNICAL FIELD The present invention relates to a steel main pile for prestressing cliffs.

"Problems to be Solved by Conventional Techniques and Inventions" Mountain stoppers using steel parent piles such as H steel are already well known.

In order to stop this mountain, as shown in FIG.
Vertical holes are excavated at appropriate intervals using an auger machine, a soil auger machine, or the like, and the main piles 1 of H steel or the like are dropped (I), then root cutting is performed, and the dam 2 is inserted. hand,
While supporting it on the main pile, the uprising members 3 ... and the burrs 4 ... are appropriately assembled in the middle portion of the main pile to provide support work (II).

In this case, the parent pile 1 ...
As shown in the figure, the bending moment M is generated stepwise. In other words, in addition to the upper part facing slightly forward, most of the part faces rearward, and a bending moment M, the value of which reaches the maximum value (M · MAX) at the lower part, is generated.

Therefore, the main piles 1 are required to have a proof stress R larger than the maximum value (M · MAX), and a steel material having a considerably large cross section is required, which is very uneconomical.

The present invention seeks to eliminate such conventional drawbacks.

"Means for Solving Problems" The present invention is to attach a plate projecting to the back to the upper and lower ends of a steel parent pile, and lay a PC steel wire between both plates to make it tension, It consists of introducing prestress to the main pile.

With the above-mentioned structure, the PC steel wire may be positioned rearward and used in the same manner as the conventional method for mountain stopping, and the parent piles thus used have the same distribution state as the conventional one. Bending moment is generated, but the prestressing by the PC steel wire behind moves the bending moment forward.
As a result, the parent pile can be made reasonably small and the intended purpose can be achieved.

"Embodiment" FIGS. 1 to 3 show an embodiment of the present invention.

In the parent pile 1 made of H steel for mountain cleat, a horizontal plate 11 protruding rearward is provided at the upper end, and a lower plate is provided at the lower end.
A vertical plate 12 protruding rearward is provided, and two steel wire fastening means 13, 13 are provided on the horizontal plate 11 on the left and right, and a pin 14 is fixed to the vertical plate 12 by penetrating and fixing the same.
Between the left end of 14 and the steel wire fastening means 13 on the left side, and between the right end of the pin 14 and the steel wire fastening means 13 on the right side, PC steel wires 15 and 15 are respectively laid, and the upper end is tightened with a jack or the like to tighten the steel. The wire fastening means 13 and 13 are activated to introduce prestress. The degree of prestress is selected in consideration of the bending moment generated in the main pile 1.

In order to stop the mountain, vertical holes are drilled at appropriate intervals using an auger machine, a soil hoger machine, etc., and the main piles 1 ... are dropped with the PC steel wires 15 and 15 positioned rearward, respectively. Then, root cutting is performed, the weir board 2 is inserted to be supported by the main pile 1, and the brackets 5, 5 are attached at appropriate positions on the back surface of the middle portion of the main pile. Uprising material 3 and shavings 4 through filling concrete 6,6
... is incorporated, and support work is performed.

In this case, before the root cutting, the bending moment M generated in the main pile 1 has a uniform distribution state toward the front as shown in FIG. 3I, and finally, FIG. As shown in Fig. 1, the one with the same distribution as the conventional PC steel wire 1
It will be in a state of being pushed forward by the prestress of 5,15.

The amount of movement of this extrusion may be set so that the integral values of the positive region a and the negative region b are equal, and prestress may be introduced to meet this.

The number of PC steel wires is not limited to two as long as it is suitable for the prestress required for calculation. The same applies to the thickness and the like.

[Advantages of the Invention] According to the present invention, since the parent pile can be used in a rational and dynamic manner, the cross-sectional shape of the parent pile can be made small, and the uprising member and the shavings can be reduced, so that the iron The amount can be greatly reduced, the cost can be reduced, and resource saving can be realized.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a side view of a state of use, FIG. 2 is a rear view, and FIGS.
Is a bending moment diagram, FIGS. 4 and 5 show a conventional example, FIGS. 4 and 5 are process explanatory diagrams, and FIG. 5 is a bending moment diagram. 1 ... Parent pile, 2 ... Weirboard 3 ... Rising material, 4 ... Cutter, 5 ... Bracket, 6 ... Backfill concrete 11 …… Horizontal plate, 12 …… Vertical plate 13 …… Steel Wire fastening means, 14 …… pin 15 …… PC steel wire

Claims (1)

[Claims] Claims: 1. A plate projecting to the rear is attached to the upper and lower ends of a steel parent pile, and a PC steel wire is installed between both plates to make them tensioned, and prestress is introduced to the steel parent pile. Steel parent pile for prestressed mountain stop, which is characterized by.