JPH047417B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an anchor structure for the lower end reinforcement of a PC girder to a column.

(Prior art) Conventionally, in this type of anchor structure, as shown in FIGS. 5 and 4, the protruding end portion 1b of the lower end reinforcement 1b of the PC girder A is extended from the left and right into the anchoring zone of the column B. , curved upwards.

(Problem to be solved by the invention) At this time, if the lower end reinforcements 1b of the opposing PC girders A are arranged at the same position, they will interfere with each other, so the reinforcements are arranged so that they are shifted from each other by the minimum interval of the reinforcing bar diameter. has been done.

Therefore, it was necessary to manufacture the PC girder A so that its width was approximately 50 mm wider, and for this reason, extra lower end reinforcement was placed in the area with large cover as shown at 1a', and the stirrup 8 was also Processed to a slightly larger size.

As a result, the weight of the PC girder itself increases, making it difficult to transport and
There was a problem that it affected work at the site.

(Means for Solving the Problems) The present invention was proposed to solve the above problems, and the present invention is directed to a vertical thickness connected between the ends of a pair of lower end reinforcements on both sides of a PC girder. The ends of the U-shaped reinforcing bar to which the handle bar is attached and the intermediate lower end reinforcement sandwiched between the lower end reinforcements on both sides are respectively made to protrude into the anchoring zone of the column, and the tips of the intermediate lower end reinforcement are directed upward and bent. The present invention relates to an anchor structure for a column of a lower end reinforcement of a PC girder, which is characterized by:

(Function) In the present invention, unlike the conventional case, all the lower end reinforcements of the PC girder do not protrude from the left and right into the anchorage zone of the column, but instead a U-shaped shape is formed between the ends of the lower end reinforcements on both sides of the lower end reinforcements of the PC girder. Join the reinforcing bars and overlap the U-shaped reinforcing bars of the opposing PC girders vertically in the anchorage zone of the column. On the other hand, the end of the middle lower end reinforcement of the PC girder is made to protrude into the anchoring zone of the column and curved upward as in the conventional method, and the PC girder is anchored to the column by the U-shaped reinforcing bar. .

In this case, by using the U-shaped reinforcing bars, the anchoring length of the lower end reinforcement of the PC girder relative to the column anchoring zone is reduced compared to the conventional one; however, when attached to the U-shaped reinforcing bars, The vertical peduncle muscle can prevent the anchoring effect from decreasing.

(Effects of the Invention) As described above, in the present invention, the lower end reinforcements on both sides of the lower end reinforcements of a PC girder do not directly protrude into the anchoring zone of the column, and instead a U-shaped shape is formed between the ends of the lower end reinforcements on both sides. By joining the reinforcing bars and making the U-shaped reinforcing bars face into the anchorage zone of the column, in order to avoid interference between the protruding parts of the lower end reinforcements of the opposing PC girders as in the conventional anchor structure, This eliminates the need to shift the interval between the lower end reinforcements, prevents the width of the PC girder from becoming unnecessarily wide, and prevents unnecessary reinforcement from being placed in areas with large cover. Furthermore, it is possible to prevent the stirrup from increasing in size.

Therefore, according to the present invention, the weight of the PC girder and the number of reinforcing bars can be reduced, and a sufficient anchoring effect can be obtained by the thick vertical bars arranged on the U-shaped reinforcing bars.
This constitutes the anchor structure for the column of the lower end reinforcement of the PC girder.

(Example) The present invention will be described below with reference to the illustrated embodiments.

A is a PC girder, and at the ends of the lower end reinforcements 1a and 1a on both sides, vertical thick reinforcing bars 2 are driven into the PC pillar material, and the U-shaped reinforcing bars 3 installed integrally are connected to the gas They are joined by pressure welding or the like.

Then, the U-shaped reinforcing bar 3 of the PC girder A that faces the
3 to protrude so as to overlap vertically within the anchorage zone of pillar B, and each of the PCs
Tips 1b', 1 of intermediate lower end reinforcements 1b, 1b of girder A
b' protrudes into the anchorage zone of column B, the tips 1b' and 1b' of the lower end reinforcements are bent upward, and column concrete is poured to connect the lower end reinforcements of each PC girder A to column B. It is something that anchors.

In the figure, 4 and 4' are column bars, 5 and 5' are hoop bars, and 6 is
Joint concrete between PC girder A and PC floor slab C, 7
is the girder top reinforcement, 8 is the stirrup, and 9 is the width stop reinforcement.

According to the illustrated embodiment, the relative
Without making the lower end reinforcements 1a, 1a on both sides of the PC beams A, A directly protrude into the anchoring zone of the column B, the U-shaped reinforcing bars 3 are connected between the ends of the lower end reinforcements 1a, 1a on both sides of the PC girders A, A, and By making the U-shaped reinforcing bars 3, 3 of the PC girders A, A protrude so as to overlap vertically in the anchorage zone of the column B, the PC girders A, A facing each other can be Eliminates the need to shift the spacing of the bottom reinforcements to avoid interference with the protruding parts of the bottom reinforcements, suppresses the increase in the width of the PC girder A, and prevents the placement of extra reinforcing bars in areas with large cover. This is to prevent the stirrup 8 from increasing in size.

Therefore, it is possible to reduce the cross section and amount of reinforcing bars of the PC girder A, and furthermore, by the thick vertical reinforcing bars 2 arranged inside the U-shaped reinforcing bars 3, the column B of the lower end reinforcement of the PC girder A can be reduced. This can improve the anchoring effect for

Although the present invention has been described above with reference to embodiments, the present invention is, of course, not limited to such embodiments, and can be modified in various ways without departing from the spirit of the present invention. .

[Brief explanation of drawings]

FIG. 1 is a cross-sectional plan view showing an embodiment of the anchor structure for the column of the lower end reinforcement of the PC girder according to the present invention;
Figure 2 is a view taken from the direction of the arrow in Figure 1, Figure 3 is a slope view showing the end of a PC girder, Figure 4 is a vertical cross-sectional view showing the anchor structure of the conventional lower end reinforcement of a PC girder for a column, and Figure 5 The figure is a view taken from the arrow in FIG. 4. A...PC girder, B...column, 1a...bottom reinforcement on both sides, 1b...middle bottom reinforcement, 2...vertical thick stalk, 3
...U-shaped reinforcing bar.

Claims (1)

[Claims] 1 A U-shaped reinforcing bar with a vertical thick handle attached between the ends of a pair of lower end reinforcements on both sides of a PC girder, and an end of an intermediate lower end reinforcement sandwiched between the lower end reinforcements on both sides of the column, respectively. An anchor structure for a column of a PC girder bottom reinforcement, which projects into the anchorage zone and is formed by curving the tip of the middle bottom reinforcement in an upward direction.