JPH07158094A - Inversely driven beam construction method and form at side of driven beam - Google Patents

Abstract

PURPOSE:To eliminate a work for back filling an outbreak and overhauling a form, and provide a driven beam side form having high durability suitable for an inversely driven beam construction method and allowing easy use by placing levelling concrete to be removed at the time of the next excavation as a form on the lower side of a beam and under a slab, and using a driven beam side form of inorganic fiber mixed cement as a beam side form, regarding an inversely driven construction method. CONSTITUTION:Levelling concretes 3 and 4 are placed under slab on an excavated bottom 2 and on a beam bottom positioned one step lower than the slab, and a driven beam side form 8 having circular longitudinal cross section and formed out of inorganic fiber mixed cement slab is erected between the internal edge of the concrete 3 and the external edge of the concrete 4. Also, after concrete placed on the concrete 3 or 4 shows the required strength, the next excavation work is undertaken and both of the concretes 3 and 4 are removed during the work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse-beaming construction method in which backfilling is omitted in the reverse-placing construction method, and a driving beam side formwork used in the reverse-beaming construction method.

[0002]

2. Description of the Related Art A reverse striking method for constructing an underground skeleton one after another by repeating root cutting and skeleton construction down to the basement after constructing a mountain stopper and a true pillar is already well known. This method is excellent not only in the early construction of the underground skeleton but also in that it allows the construction of the above-ground skeleton to proceed at the same time, and is currently being actively carried out.

[0003]

In this reverse casting method, after assembling the beam and slab formwork under the beam bottom and slab at the root cutting bottom, the remaining overburden space is temporarily backfilled and the backfilled soil is refilled. Since each formwork is supported by, support work can be simplified.
However, it is necessary to temporarily refill the remaining extra dug space in order to support the assembled formwork even though it is removed at the next root cutting, which is a waste of time and effort, and sometimes, Inadequate backfilling can also lead to rework. Therefore, in the invention of the reverse beam construction method of the present invention, the waste concrete to be removed at the time of the next root cutting is placed, and this is used as the beam bottom and the formwork under the slab, and the beam is used. It is an object of the present invention to solve the above problems by using a driving beam side mold which is previously molded with inorganic fiber mixed cement for the side mold, and the driving beam side mold of claim 2 is the present invention. The purpose of the present invention is to provide an easy-to-use one suitable for the reverse beam construction method of No. 1.

[0004]

In order to achieve the above-mentioned object, the invention of the method for constructing a reverse striking beam according to claim 1 is a reverse striking method.
Between the slab of the root cutting bottom and the portion of the beam bottom that is one step lower than the bottom of the slab, waste concrete is cast, and between the inner edge of the beam bottom waste concrete and the outer edge of the slab lower waste concrete corresponding to the inner edge. In this method, a cast beam side formwork with an arcuate vertical cross section, which is a cement molded plate containing inorganic fibers, is erected, and the next concrete root cutting is performed after the specified strength is exhibited in the cast concrete on the beam bottom concrete or slab bottom concrete. At that time, it is characterized in that the concrete discarded at the bottom of the beam and the concrete discarded under the slab are removed.

Further, the invention of the driving beam side form according to the second aspect of the present invention is to form a plate body having an arcuate vertical cross section with an upper end being warped by an inorganic fiber mixed cement, and having a rib on the peripheral edge and a lower end surface. The present invention is characterized in that it has an engaging groove, and a cap nut is driven into an appropriate position of a rib on the warped upper surface and is formed into a series of arrangable forms.

[0006]

With the above construction, in the invention of the method for constructing a reverse beam according to claim 1, not only the beam bottom waste concrete and the slab lower waste concrete function as the beam bottom mold and the slab lower mold. , It is possible to remove together with the root cutting soil at the time of the next root cutting, and the driving beam side formwork makes it unnecessary to backfill the overburden space and is integrated with the concrete after the concrete is placed. , It is possible to leave it as it is. Therefore, each discarded concrete and driven beam side formwork becomes useless, except for the conventional work of dismantling the formwork after the next root cutting, and the use of wood, except for a very small amount of auxiliary use. To do.

Further, in the invention of the driven beam side formwork according to the second aspect of the present invention, the shape of an arcuate vertical section with the upper end warped changes the bending stress originally generated in the side formwork into a compressive stress. The shape is maintained, and the strength due to the characteristics of the ribs and the material is combined with it to exert a large proof stress.In addition, its shape enables easy and strong assembly to the beam bottom abandoned concrete and the slab abandoned concrete. The engaging groove on the end face allows the flexibility of mounting by the mounting hardware, and the driven cap nut enables easy and strong support by the stopper for preventing opening. Therefore, the use in the reverse beam construction method according to the above-mentioned claim 1 is possible without any trouble.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show the embodiments according to the inventions of claim 1 and claim 2. Hereinafter, the reverse beam construction method and the driven beam side formwork illustrated in the figure will be sequentially described according to the procedure of construction.

(1) In consideration of the reverse driving method, a structure pillar (not shown) is driven into the ground, the surrounding mountain retaining wall 1 (FIG. 1) is constructed, and then necessary root cutting is performed. In this case, the root-cutting bottom 2 (FIGS. 3 and 4) forms the portion of the beam A / column B to be constructed in a groove shape which is deeper than the portion of the slab C and slightly wider than the width of the beam. -Before each part corresponding to a pillar and a slab, excess digging suitable for placing the beam bottom concrete 3 and the slab bottom concrete 4 to be constructed in the next step. The lower peripheral edge of the slab of the root-cutting bottom 2 is slightly lowered (FIGS. 3 and 4).

(2) A beam bottom concrete 3 and a slab bottom concrete 4 are placed on the root cutting bottom 2 (FIG. 3, FIG.
(Fig. 4). At this time, appropriate dams (not shown) are arranged at the ends of these discarded concretes to properly stop them and to secure a predetermined horizontal level. In addition, a wooden frame (not shown) for discarding concrete is disposed on the outer edge of the concrete 4 under the slab to make the outer edge recessed, and further the level adjusting bolts 7 are provided at required portions of the recess 5.
The cap nut 6 screwed in is driven (FIGS. 3 and 4).

(3) After the required strength is developed in the beam bottom concrete 3, the inner edge of the beam bottom concrete is
The marking corresponding to the lower part of the driving beam side mold 8 to be incorporated later and the marking of the beam position are performed, the steel beam 9 is installed, and the beam reinforcement 10
To arrange.

(4) A beam bottom edge cut material 11 such as a synthetic resin sheet and a slab lower edge cut material 12 are laid on the above-mentioned beam bottom waste concrete 3 and slab bottom waste concrete 4 (FIGS. 3 and 4), The hole-in anchors 13 are attached to the inner edges of the beam bottom concrete 3 at required places according to the marking for the driving beam side formwork, and the hole-in anchors support the fixed hardware 14 for the driving beam side formwork. (FIGS. 3 and 4). And
Arrange the required columns (not shown). The hole-in anchor 13 is equipped with a female screw anchor 15 to be fixed in the drilled hole provided in the beam bottom concrete 3, a bolt 16 screwed to the female screw anchor, and to fix the fixing hardware 14 to the bolt. It consists of a nut 17 and a washer 18 (Fig. 4). Further, as shown in FIGS. 14 and 15, the fixed hardware 14 is a rectangular steel plate and is fitted to the engaging groove 19 of the driving beam side frame 8 from the front edge of the horizontal mounting base 20. A pair of engagement projections 21 and a pressure-supporting piece 22 that abuts on the lower edge outer edge of the driving beam side form frame 8 between the engagement projections are erected, and the attachment base 20 is connected to the hole-in anchor 13. A pair of left and right loose through holes 23 for attachment are formed.

(5) The height of each level adjusting bolt 7 is adjusted to build and arrange a required number of driving beam side molds 8 (FIG. 1). Most of the driving beam side molds 8 are used for the intermediate portion of the beam A shown in FIGS. 5 to 10, but some are for corners shown in FIGS. 11 to 13. These are inorganic fiber-mixed cement molded plates that are factory-produced in advance, and each of them has a plate body having an arcuate vertical cross section with an upper end warped, a rib 24 at the peripheral edge, and an engaging groove in the material length direction at the lower end surface.
19 with cap nuts 25 in place on both sides of the warped top ribs
And is compression-molded into a series of arrayable shapes. Incidentally, the inorganic fibers used in the inorganic fiber-containing cement molded plate may be existing ones such as stainless fiber, steel fiber, carbon fiber, glass fiber, for example, in the case of steel fiber, length 20 ~ 30 mm, diameter 0.5. Mix it in a volume ratio of 0.5 to 2.0% as a thing of about mm. In these driving beam side molds 8, the lower end is connected to the fixed metal piece 14, that is, the engaging groove 19 at the lower end is engaged with the pair of engaging projections 21 of the fixed metal piece, and the outer edge of the lower end is formed. The pressure bearing piece 22 of the fixed metal object is brought into contact, and the warped upper end lower surface is placed on each of the level adjusting bolts 7. Then, each level adjustment bolt 7 is finally adjusted, and each fixed metal piece 14
Adjust the position of and tighten the nut 17 to fix it. Next, the L-shaped inter-plate joint metal fittings 26 are fixed to the cap nuts 25 of the ribs with bolts 27, and the inter-plate joint metal fittings 26 are welded at their ends to the steel beam 9 to prevent the separator 28 from opening. Tighten the tip of the nut with the nut 29 to fix it (FIGS. 3 and 4). Further, the dent 5 is filled with mortar 30, and a joint bar 31 is applied to the inner corner portion between the mortar and the end face of each driving beam side mold 8 to fix it (FIGS. 3 and 4).

(6) Thereafter, the concrete slab is discarded 4
Slab reinforcement (not shown) is applied in the upper or driving beam side form 8 and concrete of beams A, pillars B and slabs C is cast and hardened with a certain degree of curing, and the cast concrete is given a predetermined size. When strength appears, the next root cutting is performed.
At the time of this root cutting, each of the driven beam side molds 8 to the opening prevention separator 30 is driven and left as it is, the beam bottom discard concrete 3, the slab bottom discard concrete 4, the beam bottom edge cutting material 11,
Lower slab cutting material 12, cap nut 6, level adjustment bolt 7,
Hole-in anchor 13, fixed hardware 17, mortar with 5 recesses
Remove all 30 and joint bars 31 (Fig. 2).

[0015]

According to the invention of the reverse beam construction method of claim 1, in addition to the driven beam side formwork, the beam bottom discard concrete and the slab bottom discard concrete work as the beam bottom formwork and the slab bottom formwork. Therefore, the conventional wooden formwork becomes unnecessary, and the backfilling process for backfilling the excess dug space for supporting the assembled formwork as in the past can be omitted, and the time and labor for that can be eliminated. It is possible to eliminate the need for rework resulting from insufficient backfilling. Moreover, not only can the casting beam side formwork be left as it is, but the beam bottom waste concrete and slab bottom concrete can be easily removed together with the root cutting soil at the next root cutting. It is possible to eliminate troublesome formwork dismantling work. Therefore, the construction period can be shortened and the cost can be reduced. In addition, the surface has a finish similar to that of exposed concrete, which can improve quality and can also support the flexibility of the shape of the design. In addition, since no wooden formwork is required, the use of wood can be significantly reduced, which in turn reduces industrial waste.

According to the invention of the driven beam side formwork of claim 2, the bending stress originally generated in the side formwork can be changed to the compressive stress from the form of the arcuate vertical cross section having the upper end warped. In addition to the strength of the ribs and the material, which exerts a large yield strength, it is possible to obtain tremendous strength. Furthermore, its shape enables easy and strong assembly to beam bottom concrete and slab bottom concrete. West,
Especially, the engaging groove on the lower end surface allows flexibility of mounting with the mounting hardware, and the driven cap nut enables easy and strong support with the stopper etc., so it is suitable for the reverse beam construction method. It is possible to provide products that have high durability, are easy to use, and have no hindrance.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view showing an embodiment according to the invention of the reverse beam construction method of claim 1 during construction.

FIG. 2 is a vertical sectional side view showing a state after construction of the same example.

FIG. 3 is an enlarged vertical sectional side view of a main part showing the main part of the same example during construction.

FIG. 4 is an enlarged vertical sectional side view of a main part showing the main part in FIG. 3 in a further enlarged manner.

FIG. 5 is a plan view showing an embodiment of a straight-portion formwork in the middle of the beam according to the invention of the driven-beam side formwork of the present invention.

FIG. 6 is a front view of the same example.

FIG. 7 is a side view of the same example.

FIG. 8 is a sectional view taken along the line YY of FIG.

FIG. 9 is an enlarged side view of a main part of the same example.

FIG. 10 is an enlarged cross-sectional view of the main part of FIG. 7X-X of the same example.

FIG. 11 is a plan view showing an embodiment of a mold for a corner portion of a beam according to the invention of the driven-beam side mold according to claim 2 of the present invention.

FIG. 12 is a front view of the same example.

FIG. 13 is a side view of the same example.

FIG. 14 is a side view of a fixed metal object for fixing the driving beam side mold.

FIG. 15 is a plan view of the same fixed hardware.

[Explanation of symbols]

A ... Beam B ... Pillar C ... Slab 1 ... Mountain stop wall 2 ... Root cut bottom 3 ... Beam bottom discard concrete 4 ... Slab bottom discard concrete 5 ... Dimple 6 ... Cap nut 7 ... Level adjustment bolt 8 ... Implant beam side formwork 9 ... Steel beam 10 ... Beam reinforcement 11 ... Beam bottom edge cutting material 12 ... Slab lower edge cutting material 13 ... Hole-in anchor 14 ... Fixing hardware 15 ... Female thread anchor 16 ... Bolt 17 ... Nut 18 ... Washer 19 ... Engagement groove 20 … Mounting base 21… Engagement protrusion 22… Pressure support 23… Through hole 24… Rib 25… Cap nut 26… Plate joint hardware 27… Bolt 28… Stopper separator 29… Nut 30… Mortar 31… Joint bar

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ichiro Tomura 21-21 Ginza, Chuo-ku, Tokyo Stock company Takenaka Corporation Tokyo Main Store (72) Inventor Masayuki Ogata, 21-chome, Ginza, Chuo-ku, Tokyo No. 1 Incorporated Takenaka Corporation Tokyo Main Store (72) Inventor Yasuyuki Shibata 8-21-1 Ginza 8-chome, Chuo-ku, Tokyo Incorporated Takenaka Corporation Tokyo Main Store

Claims (2)

[Claims] 1. In the reverse casting method, waste concrete is placed in the slab of the root cutting bottom and in the portion of the beam bottom that is one step lower than the bottom of the slab, and at the inner edge portion and the inner edge portion of the beam bottom waste concrete. An inorganic fiber-mixed cement molding plate is installed between the corresponding slab bottom abandoned concrete and a cast beam side formwork with an arcuate longitudinal section is erected, and the beam bottom abandoned concrete or the slab abandoned concrete is placed on the concrete. After the predetermined strength is developed, the next root cutting is performed, and at that time, the concrete discarded at the bottom of the beam and the concrete discarded at the bottom of the slab are removed. 2. An inorganic fiber-mixed cement is used to form a plate member having an arcuate vertical cross-section with an upper end protruding, a rib on a peripheral edge, an engaging groove on a lower end surface, and a rib on an upper surface in an appropriate position. A driving beam side formwork characterized in that a cap nut is driven into and molded into a series of arrangable forms.