JP6625464B2 - Welding point strength test jig - Google Patents

Description

  The present invention relates to a welding point strength test jig used for mounting a test piece to be measured on a shear measuring machine for measuring the welding point strength between reinforcing bars. More specifically, the present invention relates to a welding point strength test jig suitable for measuring a welding point strength between a linear reinforcing bar and a bent reinforcing bar in a reinforced concrete foundation beam, a foundation slab, or the like of a house.

  In a shear measuring machine that measures the strength of a welding point between reinforcing bars, a test piece is mounted using a test jig according to JIS G3551. The test piece for the shear test was obtained by welding two linear reinforcing bars in an orthogonal state, and the test jig had a cross-shaped recess for mounting and fixing the two welded linear reinforcing bars. It has. Patent Document 1 proposes an improvement for securely fixing a test piece in such a test jig.

JP-A-2007-278791

  As shown in FIG. 5A, the stirrups 101 bent in a U-shape are stitched to the upper main bar 102 and the lower main bar 103 at regular intervals, as shown in FIG. Cap tie method, etc., in which a unit bar with a strength welded structure is produced in a factory, carried into a construction site, installed, and arranged so that a cap tie 104 is bridged over the upper end opening of each U-shaped stirrup 101. It has been known. In such a construction method or in the rising portion of the foundation slab bar, the bent portion of the bent bar (for example, stirrup 101) is welded to the linear bar (for example, the lower main bar 103). The welding point 105 is, for example, a full strength welded portion welded with a welding strength higher than the yield point strength of the base material of the reinforcing steel.

  As shown in FIG. 5B, the measurement of the strength of the welding point between such a linear reinforcing bar and a bent reinforcing bar is performed by using a test specimen 110 having a welded portion having the same shape as shown in FIG. Attach and perform. The test piece 110 has a main bar 111 that is a linear bar and a stirrup 112 that is a bent bar that is bent at, for example, 90 degrees, and is fully-strength-welded at a corner of the bent portion 112 a of the stirrup 112. In the cage (weld point 113), the first reinforcing bar portion 112b linearly extends upward from the bent portion 112a of the stirrup 112, and the second reinforcing bar portion 112c extends linearly in the horizontal direction from the bent portion 112a. .

  No attention has been paid to a welding point strength test jig capable of mounting the test piece 110 including such a bent-shaped reinforcing bar in a simple and appropriate state on a shear measuring machine, and no proposal for that has been made. .

  In view of the above, an object of the present invention is to provide a welding point strength test jig capable of mounting a test piece having a bent portion to a shear measuring machine by a simple operation so that rotation or displacement does not occur. Is to provide.

In order to solve the above-described problems, the present invention provides a method of welding a test piece in which a straight reinforcing bar and a bent reinforcing bar are fully-strength-welded in a state where they are orthogonal to each other at a corner portion of a bent portion of the bent reinforcing bar. In order to measure, a welding point strength test jig used to attach the test piece to a shear tester,
A bearing portion having a bearing surface for supporting the linear reinforcing bar, and a mounting groove for mounting a first reinforcing bar portion linearly extending to one side from the bent portion of the bent reinforcing bar. When,
A chuck portion for chucking a second reinforcing bar portion linearly extending from the bent portion to the other side of the bent reinforcing bar;
Has,
The mounting groove extends in a direction orthogonal to the bearing surface, and one end is open to the bearing surface.
The chuck portion grips the second reinforcing bar from both sides in the direction of the width of the mounting groove.

  A test piece is attached and fixed to the welding point strength test jig attached to the shear measuring machine as follows. The first reinforcing bar portion of the bent reinforcing bar is mounted in the mounting groove so that the linear reinforcing bar of the test piece contacts the bearing surface of the supporting portion, and the second reinforcing bar portion is chucked by the chuck portion. Since the mounting groove extends in a direction orthogonal to the bearing surface, the linear reinforcing bar is pressed against the bearing surface, and the first reinforcing bar portion of the bent reinforcing bar is mounted in the mounting groove. Rotation in the direction perpendicular to the pressure surface is prevented. Further, since the second reinforcing bar portion of the bent reinforcing bar is chucked by the chuck portion from the width direction of the mounting groove, rotation and displacement of the linear reinforcing bar in the direction along the bearing surface are prevented.

  In this state, a tensile force is applied to the first reinforcing bar portion of the bent reinforcing bar of the test piece in the axial direction by the shear measuring machine, and the welding point strength is measured. As described above, since rotation and displacement of the linear rebar are prevented, the strength of the welding point can be accurately measured.

  Here, the welding point strength test jig can be configured to include a jig housing provided with a concave portion having open ends on both sides. In this case, a support plate fixed to the jig housing at a predetermined height position in the recess can be used as the support portion, and the support surface is provided on the bottom surface of the recess in the support plate. It is formed on the opposite back surface. The mounting groove is open at an end face of the support plate facing one opening end of the concave portion, and is formed to extend linearly in a vertical direction of the concave portion. Further, the chuck portion is disposed in the jig housing at a position on the other open end side of the concave portion with respect to the support plate in the concave portion.

  In addition, the chuck portion may include, for example, a pair of wedge surfaces in which an interval in the width direction of the concave portion is gradually reduced toward the support plate along a length direction of the concave portion, and each of the wedge surfaces. A pair of inner chucks having a wedge shape slidable along the length of the recess along the length of the recess, and a groove extending in the length direction of the recess formed between the inner chucks. desirable. In this case, the groove width of the groove decreases when the pair of inner chucks slides in the direction toward the support plate along the length direction of the recess, and increases when the pair of inner chucks slide in the opposite direction.

  The second rebar portion of the bending rebar of the test piece is passed through the groove formed between the pair of inner chucks, and the pair of inner chucks is pushed along the wedge surface, whereby the second rebar portion is securely formed by the wedge effect. Can be chucked. Further, the second reinforcing bar portions of the bending bars having different outer diameters can be reliably chucked.

It is a perspective view showing a welding point strength test jig to which the present invention is applied. FIG. 2 is an AA cross section, a plan view, and a BB cross section of the welding point strength test jig of FIG. 1. FIG. 2 is a front view, a sectional view taken along line CC, and a sectional view taken along line DD of the welding point strength test jig of FIG. 1. FIG. 2 is a plan view and an outer side view showing an outer chuck of the welding point strength test jig of FIG. 1, and an inner side view, a plan view, and an outer side view showing an inner chuck. It is explanatory drawing which shows an example of the reinforcement of a foundation beam, and an example of a test piece to be measured.

  Hereinafter, embodiments of a welding point strength test jig to which the present invention is applied will be described with reference to the drawings. The welding point strength test jig according to the present embodiment is, for example, a test jig for arranging a reinforcing bar of a foundation beam by a cap tie method, and is used for welding a test piece 110 having a shape shown in FIG. This is for testing (measuring) the strength of the point 113.

  FIG. 1 is a perspective view showing a welding point strength test jig according to the present embodiment (hereinafter, simply referred to as “test jig”). FIG. 2A is a sectional view taken along line AA of the test jig 1 taken along the line AA, and FIG. 2B is a plan view of the test jig 1 and FIG. () Is a BB line sectional view showing a portion of the test jig 1 cut along the BB line. FIG. 3A is a front view showing a front end face of the test jig 1, and FIG. 3B is a cross-sectional view taken along a line CC of FIG. 2A. FIG. 3C is a sectional view taken along line DD of FIG. 2A, taken along line DD.

  As shown in these figures, the test jig 1 includes a jig housing 2, a support plate 3 (support portion) attached to the jig housing 2, and a chuck portion 4 also attached to the jig housing 2. It has. The jig housing 2 includes a rectangular bottom plate 6 that is long in the front-rear direction 5 indicated by the arrow, a left wall plate 7L, a right wall plate 7R, and a bottom plate 6 that are vertically fixed to the upper surfaces of the long left and right edges of the bottom plate 6. A fixing plate 8 extending vertically downward from the rear surface. The fixing plate 8 is a part to be attached to a shear measurement device (not shown).

  The bottom plate 6, the left wall plate 7L, and the right wall plate 7R form a recess 9 having a constant depth and a constant width, which opens upward and in the front-rear direction. The supporting plate 3 is arranged on the side of the opening 9b on the rear side in the recess 9. The support plate 3 is a rectangular plate having a constant thickness, and is horizontally hung between the left wall plate 7L and the right wall plate 7R at a predetermined height from the bottom plate 6. For example, as shown in FIG. 2B, the supporting plate 3 is provided with two fastening bolts 11L and 11R screwed from the outside of the left wall plate 7L and the right wall plate 7R, respectively. It is fixed to the plate 7R.

  The back surface of the support plate 3 is a horizontal support surface 3 a extending in the front-rear direction 5. As can be seen from FIGS. 2A and 3C, the main reinforcing bar 111, which is a linear reinforcing bar of the test piece 110, is pressed against the bearing surface 3a from below. Further, a mounting groove 3b extending in the vertical direction is formed at the central position in the width direction of the rear vertical end face facing the rear open end 9b of the support plate 3.

  2 (a) and 2 (b), the mounting groove 3b is open rearward, and its lower end 3c is open on the bearing surface 3a, and its upper end 3d is open on the upper surface 3e of the support plate 3. are doing. The mounting groove 3b is a groove of a constant width whose groove bottom surface 3f is a concave curved surface, for example, a semicircular curved surface. The mounting groove 3b is set to a groove width in which the stirrup 112 of the test piece 110 can be mounted.

Next, the chuck portion 4 is a portion for chucking the horizontally extending second reinforcing bar portion 112c of the stirrup 112, which is the bent reinforcing bar of the test piece 110, from both sides. The chuck portion 4 is arranged in the concave portion 9 at a position on the front opening end 9a side with respect to the supporting plate 3. The chuck section 4 includes a fixed plate 21, left and right outer chucks 22L and 22R, and left and right inner chucks 23L and 23R.

  The fixed plate 21 is a rectangular plate having a constant thickness, and is horizontally bridged between the left wall plate 7L and the right wall plate 7R at a position at a predetermined height from the bottom plate 6 in the concave portion 9. As can be seen from FIG. 2B, the fixing plate 21 is fixed to the left wall plate 7L and the right wall plate 7R by two fastening bolts 24L and 24R from both sides. The left wall plate 7L and the right wall plate 7R are formed with recesses 25L and 25R having a constant width extending in the vertical direction, and the fixing plate 21 is moved left so that the left and right ends are fitted into these recesses 25L and 25R. It is mounted and fixed between the wall plate 7L and the right wall plate 7R.

  Here, the depressions 25L and 25R of the left wall plate 7L and the right wall plate 7R are formed from their upper ends to the bottom plate 6, and as shown in FIG. Is formed. The depression 26 of the bottom plate 6 is formed up to the front end of the bottom plate. The left and right outer chucks 22L, 22R are attached to these recesses 25L, 25R, 26.

  4A and 4B are a plan view and an inner side view showing the outer chucks 22L and 22R, and FIGS. 4C to 4E are an inner side view and a plan view showing the inner chucks 23L and 23R. It is a figure and an outer side view.

  As can be seen from FIGS. 2C, 4A and 4B, the outer chucks 22L and 22R are rectangular plates having a wedge-shaped cross section whose thickness gradually increases from the front to the rear. Between the bottom plate 6 and the fixing plate 21 in the concave portion 9, the left outer chuck 22L is fitted and fixed in the depression 25L of the left wall plate 7L and the left end portion of the depression 26 of the bottom plate 6 continuous thereto. Similarly, the right outer chuck 22R is symmetrically fitted into the recess 25R of the right wall plate 7R and the right end of the recess 26 of the bottom plate 6 that is continuous with the recess. As a result, the inner surfaces of the left and right outer chucks 22L and 22R are wedge surfaces 27L and 27R in which the distance between them decreases from the front to the rear.

  As can be seen from FIGS. 2C and 4C to 4E, the left and right inner chucks 23L and 23R are rectangular plates having the same wedge-shaped cross section. As can be seen from FIG. 2C, between the bottom plate 6 and the fixed plate 21, the left and right outer chucks 22L and 23R are slidably mounted on the wedge surfaces 27L and 27R of the left and right outer chucks 22L and 23R. Since the wedge surfaces 27L and 27R of the outer chucks 22L and 22R and the inclined surfaces of the inner chucks 23L and 23R have the same inclination angle, a groove 28 having a constant width in the front-rear direction is provided between the inner chucks 23L and 23R. Is formed.

  When the left and right inner chucks 23L and 23R are slid in the front-rear direction along the left and right wedge surfaces 27L and 27R between the bottom plate 6 and the fixed plate 21, the width of the groove 28 between the inner chucks 23L and 23R is reduced. Can be increased or decreased. When the inner chucks 23L and 23R are slid backward, the groove width of the groove 28 decreases, and when the inner chucks 23L and 23R slide in the opposite direction, the groove width increases.

  A second reinforcing bar portion 112c extending horizontally in front of a stirrup 112, which is a bent reinforcing bar of the test piece 110, is passed through the groove. By sliding the left and right inner chucks 23L and 23R backward while passing through the second reinforcing bar portion 112c, the second reinforcing bar portion 112c can be chucked and fixed from both sides by the left and right inner chucks 23L and 23R.

  Here, as shown in FIGS. 4C and 4D, the inner side surfaces of the inner chucks 23L and 23R are provided with a reinforcing bar chuck surface 29 in which uneven portions extending in the vertical direction are formed at a constant pitch in the front-rear direction. Has become. The chucking force of the reinforcing bar is increased by the reinforcing bar chuck surface 29 having an uneven surface.

  A test piece 110 is mounted and fixed to the test jig 1 having this configuration as follows. As shown in FIG. 1, the horizontally extending second reinforcing bar portion 112 c of the stirrup 112 of the test piece 110 is moved from the opening end 9 b behind the concave portion 9 to the lower side of the support plate 3 and the groove 28 of the chuck portion 4. And put forward through. Then, the first reinforcing bar portion 112b extending above the stirrup 112 is mounted in the mounting groove 3b of the support plate 3 from behind, and the main bar 111 is pressed against the support surface 3a on the back side of the support plate 3 from below. In this state, the left and right inner chucks 23L and 23R of the chuck portion 4 are slid rearward from the front side, and the second reinforcing bar portion 112c of the stirrup 112 is chucked from both sides between them.

  As a result, as shown in FIG. 2A, the main bar 111 is pressed against the bearing surface 3a of the pressure plate 3 from below, so that the vertical rotation of the main bar 111 is prevented. Further, as shown in FIG. 2C, the second reinforcing bar portion 112c of the stirrup 112 is chucked from both sides in the width direction by the chuck portion 4, and the first reinforcing bar portion 112b of the stirrup 112 is vertically attached to the mounting groove. Since the main bar 111 is pressed against the bottom surface 3f of the main bar 3b, the main bar 111 is prevented from rotating in the front-rear direction and being displaced in the front-rear direction. In this state, a tensile force is applied to the first reinforcing bar portion 112b extending above the stirrup 112 in the axial direction by a shear measuring machine (not shown), and the strength of the welding point 113 is confirmed. (Measured). Since the main bar 111 is securely fixed so as not to move, the strength of the welding point 113 can be confirmed (measured) accurately.

REFERENCE SIGNS LIST 1 test jig 2 jig housing 3 supporting plate 3 a supporting surface 3 b mounting groove 3 c lower end 3 d upper end 3 e upper surface 3 f groove bottom 4 chuck portion 5 front-back direction 6 bottom plate 7 L left wall plate 7 R right wall plate 8 fixing plate 9 recess 9 a front side Opening end 9b Rear opening end 11L, 11R Fastening bolt 21 Fixing plate 22L, 22R Outer chuck 23L, 23R Inner chuck 24L, 24R Fastening bolt 25L, 25R Depression 26 Depression 27L, 27R Wedge surface 28 Groove 29 Rebar chuck surface 110 Test Piece 111 Straight bar (main bar)
112 Folded reinforcing bars
112a Folded portion 112b First reinforcing bar portion 112c Second reinforcing bar portion 113 Welding point

Claims (4)

In order to measure the welding strength of a test piece that has been fully-strength welded so that a straight reinforcing bar and a bent reinforcing bar are orthogonal to each other at a corner portion of the bent portion of the bent reinforcing bar, the test piece is subjected to a shear tester. A welding point strength test jig used for attaching to a
A bearing portion having a bearing surface for supporting the linear reinforcing bar, and a mounting groove for mounting a first reinforcing bar portion linearly extending to one side from the bent portion of the bent reinforcing bar. When,
A chuck portion for chucking a second reinforcing bar portion linearly extending from the bent portion to the other side of the bent reinforcing bar;
Has,
The mounting groove extends in a direction orthogonal to the bearing surface, and one end is open to the bearing surface.
The welding point strength test jig, wherein the chuck portion grips the second reinforcing bar portion from both sides in a direction of a groove width of the mounting groove. In claim 1,
It has a jig housing with a concave part whose both sides are open ends,
The supporting portion includes a supporting plate fixed to the jig housing at a predetermined height position in the concave portion,
The bearing surface is formed on a back surface facing a bottom surface of the concave portion in the bearing plate,
The mounting groove is open on an end surface of the support plate facing one open end of the concave portion, and extends in a vertical direction of the concave portion,
The welding point strength test jig, wherein the chuck portion is fixed to the jig housing at a position on the other open end side of the concave portion with respect to the supporting plate in the concave portion. In claim 2,
The chuck section includes:
A pair of wedge surfaces, in which the interval in the width direction of the concave portion gradually decreases toward the support plate along the length direction of the concave portion,
A pair of inner chucks having a wedge shape slidable along the length of the recess along each of the wedge surfaces;
A groove extending in the length direction of the concave portion formed between the inner chucks,
With
A welding point strength test jig wherein the groove width of the groove decreases when the pair of inner chucks slides in the direction toward the support plate along the length direction of the recess, and increases when the pair of inner chucks slide in the opposite direction. In claim 3,
The jig housing includes a bottom plate, and a left wall plate and a right wall plate fixed to both side edges of the bottom plate,
The concave portion is formed between the bottom plate, the left wall plate, and the right wall plate,
The support plate is fixed to the left wall plate and the right wall plate in a state of being bridged between the left wall plate and the right wall plate,
The chuck section includes:
In a state of being bridged between the left wall plate and the right wall plate, a fixed plate fixed to the left wall plate and the right wall plate,
A pair of outer chucks fixed to the left wall plate and the right wall plate between the bottom plate and the fixing plate, and the wedge surface is formed,
With
A welding point strength test jig, wherein the pair of inner chucks are mounted between the bottom plate and the fixing plate so as to be slidable in the length direction of the recess along each of the wedge surfaces.

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