JPH0751805B2 - Joining method for half precast concrete beam and half precast concrete beam - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to the incorporation of a half precast concrete beam (hereinafter referred to as “half PC beam”) into a half precast concrete beam (hereinafter referred to as “half PC beam”). Easy-to-use and easy-to-install, half PC that can completely satisfy design strength and structural regulations by regulations
The present invention relates to a method for joining a small beam and a half-PC large beam.

[Prior Art] In recent years, in construction of a building, a method of converting a large beam and a small beam into half PCs and combining them with a half PC slab has become widespread as one means for reducing a construction period and a construction cost.

Therefore, if both the large beam and the small beam are made of half-PC, the half-PC small beam is joined to the half-PC large beam, but the girder under the small beam does not receive tensile force. By forming ribs in three directions to receive, placing a beam on this rib, and placing slab concrete on the upper surface of the half PC girder and half PC girder, without fixing the bottom beam of the girder to the girder , A method of joining a half-PC girder to a half-PC girder has been proposed.

[Problems to be Solved by the Present Invention] However, in the method of joining the half-PC beam and the half-PC beam which do not fix the underbeam of the beam to the beam, the beam of the beam is fixed to the beam. It would violate the structural regulations of the current legislation that regulates. Therefore, in order to satisfy the current laws and regulations, in the same way as in the conventional method, when extending the fixing extra length of the stirrups from the small PC beam's edge and fixing it to the girder, the half PC beam will be When installing in a large beam, the fixing extra length of the bottom rib of the above half PC small beam hits the upper rib of the big beam, so the upper rib should be moved to one side or the lower rib should be bent. However, the construction was very troublesome.

In view of the above-mentioned present situation, the present invention is a half-PC girder, which is very easy to install the girders with each other and has good workability, and further, the half-PC girder and the half-PC girder that can completely satisfy the current regulations. The object is to provide a joining method.

[Means for Solving the Problems] In order to solve the above problems, a technical means adopted by the present invention is to join a side surface of a half precast concrete girder having a groove cross section with a larger cross section than a small cross section of the half precast concrete girder. An opening is formed, and a small precast concrete beam with a groove having a predetermined depth is formed in the joint opening. The post-insertion bottom bar is arranged from the concave groove of the half precast concrete beam to the middle groove of the half precast concrete beam, and then the slab concrete is post-cast to join the half precast concrete beam and the half precast concrete beam. It is characterized by doing so.

[Operation] Therefore, according to the present invention, since the extra fixing length of the streak does not extend to the stoma of the half-PC beam, the half-PC beam can be easily incorporated into the half-PC beam without any hindrance. It is possible to fix the streaks under the half-PC beam to the half-PC beam.
Since the reinforcement is performed after the reinforcement is done by arranging from the concave groove formed in the small PC small beam to the middle groove of the half PC large beam of groove shape in cross section, the current law that defines the fixation of the lower beam of the small beam to the large beam is required. You can be completely satisfied.

Moreover, the joint opening of the half PC girder is
By making the cross section of the beam smaller than the cross section of the beam, the joint opening becomes a construction clearance when suspending the half PC beam, and it is easy to assemble. By arranging a gap on the left and right side surfaces and the lower surface, and by incorporating it slightly, the side surface and the lower surface of the half PC beam do not become a bad opening, and the post-cast slab concrete is the groove of the half PC beam, Not only does it reach the middle groove of the half-PC girder, but it also goes into the gap between the edge of the half-PC girder and the joint opening of the half-PC girder, so the joining of the two beams becomes even more reliable.

[Embodiment] The present invention will be described in detail below based on an embodiment shown in the drawings.

FIG. 1 is a cross-sectional view taken along the line II of the plane cross-sectional view taken along the line I-I in FIG. 2 before the post-casting concrete is placed after joining the half-PC large beam and the half-PC small beam constructed by the method of the present invention. Is a plane sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a sectional view of FIG.
FIG. 4 is an end view of the half-PC beam, taken along the line III-III in FIG.

In the figure, 1 is a half-PC large beam with a groove section in which a middle groove 1a is formed in the beam direction. The inner surface of the middle groove 1a serves as a mold for precasting, and a rib lath 1c is used to improve the adhesion of post-cast concrete. Has become. In the middle groove 1a, girder upper braces 2, girder lower braces 3, girder stirrup 4, auxiliary reinforcements 5 are arranged, and auxiliary reinforcements 6 are embedded in the lower part of the half PC concrete. A joint opening 1b having a cross section that is appropriately larger than the small cross section of the half PC beam 7 is formed at the joint.

Half PC beam 7 is a groove with a certain depth length
7a is formed, and the inner surface of the concave groove 7a is also used as a mold for precasting, and is a rib lath 7b to improve the adhesion of the post-cast concrete. The girder bottom streak 8 is embedded without extending the fixing length from the girder forehead surface, and the girder stirrup 9 is a loop-shaped part of the full PC half girder 7 as well as the conventional one. At least part of the groove 7a is of a split type in which U-shaped stiffeners 9a and 9b are combined vertically, and the upper parts of the beam girder stirrup 9 and girder stirrup 4 are fixed to the slab concrete 10 to be stamped. Therefore, it is exposed above the upper surfaces of both beams 1 and 7 as appropriate.

Two inserts 11 are embedded in each of the left and right sides of the edge of the half-PC beam 7 in the direction of the beam, and a three-way form 12 as shown in FIG. It is designed to be installed by. The three-sided frame 12 is a three-sided surface 12a that surrounds the left and right side surfaces and the lower surface of the edge of the half-PC beam 7.
And a U-shaped flat surface 12b that is in contact with the peripheral surface of the joint opening 1b of the half-PC girder 1 that is orthogonal to the half-PC girder 1, and can be moved back and forth in the longitudinal direction of the half-PC girder 7 by the long hole 12c on the side surface. There is.

Half PC girder 7 and half PC girder 1 are joined by half PC
The three-sided form 12 is retracted from the forehead surface and attached in advance to the beam 7, and the gaps 14 are arranged on the left and right side surfaces and the lower surface of the window, and the half PC beam 7 is connected to the joint opening 1b of the half PC girder 1.
Support it with a built-in support 15 with a slight intrusion. And from the concave groove 7a of the half PC beam 7 to the middle groove 1a of the half PC beam 1.
The half 16 PC beam 7 is rearwardly inserted and the bar 16 is arranged.
The rear reinforcement 16 can be easily arranged without any hindrance by removing the upper U-shaped line 9a of the groove 7a of the half PC beam 7.

The embodiment shown in FIGS. 1 to 3 is a case where the half PC beam 7 is continuous on both sides of the half PC beam 1 and the depth of the concave groove 7a of the half PC beam 7 is relatively shallow. Therefore, the rear insertion / removal streak 16 forms a bent rising portion having hooks at both ends to satisfy the structural strength and the structural regulation.

FIG. 6 shows that in the half PC beam 7 that is continuous on both sides of the half PC beam 1, the depth of the groove 7a of the half PC beam 7 is deepened to about 30 times the muscle diameter of the streak. When inserted, the streak 16 shows an example of a straight line with hooks at both ends.
In the half-PC beam 7 that ends on one side of the half-PC girder 1, the post-insertion bottom streak 16 has an L-shape with hooks at both ends.

Continuing from the above, the upper beam 17 of the beam is arranged, the upper U-shaped line 9a of the split beam girder stirrup 9 of the groove 7a is inserted, and the three-sided formwork is also used.
Move the 12 forward and move the front U-shaped plane 12b to the half PC girder 1
The gap 14 between the joint opening 1b and the half PC girder 7 forehead is closed by abutting on the peripheral surface of the joint opening 1b, and then slab concrete 10 is cast, and the star lap of the half PC girder 1 is lapped. The upper part of 4 and the upper stirrup 2, the upper part of the stirrup 9 of the half PC beam 7 and the upper stirrup 17 are buried, and slab concrete is used for the concave groove 7b of the half PC beam 7 and the middle groove of the half PC girder 1. 1a Spread it over, harden and cure the concrete, and remove it with the three-way form 12, support 15, etc.

[Effects of the Invention] In summary, the present invention forms a joint opening of a larger cross section than the small cross section of a half precast concrete beam on the outer surface of a half precast concrete girder having a grooved cross section, and a predetermined opening is formed in this joint opening. From the groove of the above half precast concrete beam to the half precast concrete beam with the groove of the depth is formed in the edge of the beam of the half precast concrete beam with the space on the left and right sides and the lower surface. The half PC pre-beam is designed to join the half pre-cast concrete beam and the half pre-cast concrete beam by post-injecting the slab concrete after placing the post in the middle groove. Since the extra length of streak below the beam does not extend to the edge of the
Assembling a small beam into a half PC large beam can be done easily without any hindrance, and the workability is greatly improved.
Fixing of the PC girder under beam to the half PC girder is done by arranging from the concave groove of the half PC girder to the middle groove of the half PC girder, and then inserting and inserting the girder. It can completely satisfy the current regulations that regulate the fixation.

Moreover, the joint opening of the half PC girder is
By making the cross section of the beam smaller than the cross section of the beam, the joint opening becomes a construction clearance when suspending the half PC beam, and it is easy to assemble. By arranging a gap on the left and right side surfaces and the lower surface, and by incorporating it slightly, the side surface and the lower surface of the half PC beam do not become a bad opening, and the post-cast slab concrete is the groove of the half PC beam, Not only does it reach the middle groove of the half-PC girder, but it also goes into the gap between the edge of the half-PC girder and the joint opening of the half-PC girder, so the joining of the two beams becomes even more reliable.

Furthermore, a brim-shaped three-sided form is provided on the side of the fore edge of the half PC beam so that it can move back and forth in the beam longitudinal direction, and it is retracted when the half PC beam is assembled into the half PC beam, and when slab concrete is placed. By moving forward and closing the gap between the small PC beam and the half PC beam connection opening,
Conventionally, after assembling the beam girder in the joint of the girder, in order to close the gap of the construction clearance between the girder mouth and the girder joint, hit the veneer formwork to the beam with Kunkreit nails, etc. A separator was provided, but the three-sided formwork can close the gaps on three sides at once, and it can be joined by simply retracting it from the front face when installing a half PC beam and advancing it when placing concrete. It becomes possible to set the formwork of the part, and overall, it is possible to satisfy the structural regulations, improve the workability, and reduce the construction cost.

[Brief description of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a cross-sectional view of FIG. 2 before the post-casting concrete is placed at the joint between the half-PC large beam and the half-PC small beam constructed by the method of the present invention.
-I fold line arrow side plan sectional view, FIG. 2 is a II-II fold line arrow sectional plan view of FIG. 1, FIG. 3 is a III-III line longitudinal sectional view of FIG. 1, and FIG. An end view of a half-PC beam, FIG. 5 is a perspective view of a three-sided formwork, and FIG. 6 shows another embodiment of the post-insertion bottom streak when the half-PC beam is continuous on both sides of the half-PC beam. A side view and FIG. 7 are side views showing an embodiment of a post-insertion bottom stirrup in the case where the half PC beam is terminated on one side of the half PC beam. 1 ... Half precast concrete girder, 1a ... Medium groove, 1b ... Joining opening, 7 ... Half precast concrete girder, 7a ... Recessed groove, 10 ... Slab concrete, 12 ... Three-way form, 14 ... … Gap, 16 …… Straight after inserting.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Haruhiko Umazume, Inventor 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Yusuke Yamazaki 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (56) References JP-A-57-21642 (JP, A)

Claims (2)

[Claims] 1. A concave groove having a predetermined depth depth formed in a side surface of a half-precast concrete girder having a grooved cross section, the joining opening having a larger cross section than the small cross section of the half precast concrete girder. A small precast concrete beam with a small edge is inserted with a gap on the left and right sides and the lower surface, and is inserted into the small precast concrete beam to the middle groove of the half precast concrete beam. Half-precast concrete beam and half-precast concrete beam are characterized by connecting the half-precast concrete beam and the half-precast concrete beam with post-casting of slab concrete. How to join. 2. A brim-shaped three-way form is provided on the side of the fore edge of the half precast concrete beam so as to advance and retract in the longitudinal direction of the beam, and is retracted when the half precast concrete beam is assembled into the half precast concrete girder. The half precast beam and the half precast according to claim 1, characterized in that the gap between the edge of the half precast concrete beam and the joint opening of the half precast concrete beam is advanced by advancing at the time of placing the slab concrete. How to join concrete girders.