JPH0978852A - Method of earthquake-proof reinforcement of concrete stud by steel plate and member therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct an earthquake-proof reinforcement of studs safely and quickly by surrounding a stud with split steel plates, inserting connecting members therein from window parts provided at low positions, and connecting the seamed parts of the steel plates from the inside with the connect members. SOLUTION: The stud of a concrete post 1 is surrounded with split steel plates. At the low part of straight line seamed parts 5 of the steel plates, recesses are made for forming windows, and projections are provided over the entire length and along the inside of the seamed parts 5 except the recesses. Next, connecting members 7 are inserted one by one on the inside projections 6 from the window parts, and the seamed parts 5 of the split steel plates are connected from the inside by the connecting members 7. Then, the interstices confined between the wall surfaces of the concrete post and the steel plates are filled with a hardenable fluid material such as mortar. Besides, before or after filling of mortar, the window parts are blocked by welding the plates or the like method. This process dispenses with a welding and bolt tightening operation at a height, resulting in the completion of connecting steel plates by a simple and prompt operation at a low place.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for earthquake-proofing a concrete pedestal and a member used therefor.

As a result of recent large earthquakes, it has been considered in the field of civil engineering that weak concrete pedestals should be reinforced by wrapping steel plates. The specifications for winding the steel plate vary depending on the strength of the concrete pedestal, but one specification when the concrete pedestal is not so weak is that, due to variations in the accuracy of the concrete pedestal, for example, a gap of about 30 mm. With 6 mm
A method of covering with a steel plate having a thickness and filling the gap with mortar or the like later is adopted.

[0003]

2. Description of the Related Art To reinforce an existing pedestal with a steel plate, for example, a tubular member is vertically divided into two, for example, a steel plate member having a U-shaped cross section is applied around the concrete pedestal, The members are welded to each other or bolted together.

[0004]

However, many of the tops of concrete stilts, especially those requiring reinforcement, reach extremely high places, and the fall of workers causes fatal injury. When working, there is no choice but to risk or build a huge foothold. Since the number of on-site work performed on the steel plate surface without any scaffolding, such as welding of members and joining with bolts, which are used for conventional reinforcement, increases the work risk and is inefficient. There is also an economic disadvantage. Therefore, in order to reinforce bare concrete stanchions that require many reinforcements nationwide, it is essential to develop a safe and simple construction method that can reduce on-site work.

[0005]

Means for Solving the Problems As a result of various studies on the case of connecting steel plate members to cover and reinforce the periphery of a concrete pedestal, the present inventor has tried to seam a projecting portion whose cross section always has the same shape in the longitudinal direction. Provided on the inside of the steel plate member along the portion to be formed, a position where a portion to be seamed of the steel plate member, for example, preferably at the bottom, is provided with a notch for forming a window, and the steel plate member is applied around the concrete pedestal, One or more connecting members that engage with both protrusions are inserted into both protrusions through a window while engaging with both protrusions, and a curable fluid material, that is, a grouting material such as mortar or resin is cured. A safe and simple concrete leg that can reduce the site work by filling the gap between the steel plate and the concrete pedestal, and if necessary, by closing the window by welding the iron plate before or after filling. Steel plate winding construction method of reinforcement by the it was found that can be achieved.

The present invention further relates to a tubular article forming member formed of a steel plate for reinforcing concrete pedestals used in the above-mentioned construction method. The tubular object forming member has 1) a cross section that is a part of the cross section of a tubular object that can cover the periphery of the columnar object, 2) has a straight seam portion, and 3) along the straight seam portion. The projections are provided on the inner side and have the same shape in cross section in the longitudinal direction, and 4) the notches are provided at arbitrary positions of the straight seam portions of the steel plate member. The protrusion has an engaging surface for connecting with another tubular member forming member by meshing with the connecting member, and the notch portion has another notch for forming another tubular member at the straight seam portion. The size is such that when it is connected to a member, a window having a width larger than the width of the protrusion and the width of the connecting member and having a length sufficient to assist the insertion of the connecting member is formed.

The position of the window formed by the notch and
From the standpoint of size and number of operations, it is better to position the window at the bottom.
This is because, when inserting the connecting member through the window, the work efficiency is as low as possible. Further, when it is not possible to insert it into the smooth, it is easier to obtain a reaction force for pushing the connecting member onto the protrusion when the member is closer to the ground. If there is a window above, it will be difficult to deal with any trouble.

The size of the window is preferably larger than both the width and the length of the connecting member, but the length can be the same as that of the connecting member. Because there is a gap of about 30 mm between it and the concrete pedestal, the gap under the window can be used. Especially, if the vicinity of the end of the protrusion that contacts the window is thin, The connecting member can be easily inserted on the top.

It seems that one window is sufficient in many cases, but if necessary, it may be provided at a plurality of positions in order to insert the connecting member from a plurality of positions of the pedestal.

Cross-sections of protrusions and corresponding connecting members
The protrusions have the same sectional shape in the longitudinal direction so that the connecting member can be inserted from the window side end of the protrusion, and the adjacent protruding portions are firmly connected by the connecting member. The connecting member has an engaging surface for engaging with each other without being displaced in the direction of the center of the pedestal. Preferably, as shown in FIGS. 2 and 4, the protrusion has a cross-sectional shape in which two adjacent protrusions have an inverted trapezoidal cross section. However, sectional shapes as shown in FIGS. 5 to 7 are also possible.

Position where the seam portion can be provided The seam portion is, for example, as shown in FIGS. 1 to 3 (and FIGS. 4 to 6), a pedestal having a square or rectangular cross section.
It is preferable to extend along the longitudinal direction in the middle of two facing sides of a square or a rectangle having a square or rectangular cross section of the connected steel plate members. However, as shown in the embodiment of FIG. 7, there can be seams at opposite or adjacent corners of a square or rectangle. in this case,
The cross section of the protrusion and the connecting member has an arbitrary shape as shown in the sectional view of FIG. The seam portion can be provided not only in the vertical direction but also in the horizontal direction. At this time, notches are provided at two corners of the end of the tubular body having a square cross section that covers the pedestal to form a window. Further, the seam portion may be provided obliquely as long as it is a straight line.

Method of Inserting Connecting Member The connecting member is inserted upward and / or downward from the window formed in the connected tubular member of the steel plate member and, in the case of a plurality of members, successively on the protrusions. However, in the preferred embodiment, the window is at the bottom, so that the connecting member is inserted upwardly against the weight and onto the protrusion. Therefore, the connecting member to be inserted into the protrusion should be inserted into the upper part with good dimensional accuracy so that the inserted member can be pushed up and the next connecting member can be inserted into the protrusion from the window. It is preferable that the weight of the connecting member is supported as much as possible by the frictional force with the protrusion in the state of being lifted. But,
Even if the weight of the inserted connecting member cannot be supported by the frictional force with the protruding portion, for example, by providing a screw hole or the like that penetrates the steel plate and the protruding portion on the window, the stopper that hits the surface of the connecting member The weight of the inserted connecting member can be easily temporarily supported with screws or the like. Once the connecting members are all inserted on the protrusions, the connecting members can be retained in place by suitable means. For example, in the case of covering a window by welding an iron plate, the iron plate has a shape that can serve as a stopper,
Alternatively, before welding the lid of the iron plate, the end of the protrusion near the window can be deformed in advance to form a stopper, or a stopper can be provided on the protrusion.

When a plurality of connecting members are used, they are the same.
The end faces of the plurality of connecting members that the engineer contacts do not necessarily have to be perpendicular to the vertical direction. When multiple connecting members are used,
Since it takes more weight as it goes down, if the concrete pillar side of the end faces that contact each other is higher and the steel plate side is also slightly inclined, the connecting member will be pressed against the steel plate by the sliding of the contact surface, so a better tightening will be obtained. You can

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific example of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a concrete column 1 is surrounded by two tubular object forming members 2 formed of steel plates from both sides,
From the window 4 shown in FIG. 3 formed by the cutout portion 3, the plurality of connecting members 7 are pushed up while being inserted in order from the bottom to the top on the protrusion 6 provided on the seam portion 5. . The insertion procedure is as previously described. Seam part 5
When the protrusion 6 and the connecting member 7 are engaged with each other over substantially the entire length of the above, the connecting member 7 above the window 4 is treated so as not to fall down by an appropriate method as described above, and the concrete pedestal and the steel plate are separated from each other. Fill with mortar etc. A sufficient distance from the concrete, for example 6 mm, is necessary so that the protrusion and the connecting member do not hinder the flow of the mortar during filling. After the filling is completed, the iron plate is welded to the window to close the window.

[0015]

[Effect of the present invention]

1. Work such as welding and bolting at high places where there is no foothold can be eliminated, and since the connection of steel plates can be completed only by the work that can be performed simply and quickly at a low place, it is extremely safe and convenient. , Economical. 2. Also in terms of strength, it is possible to perform construction that is no worse than steel plate winding reinforcement by welding or bolt connection. 3. Since no bolts are exposed on the surface, painting is easy and the appearance is beautiful. 4. Since the joint is on the side of the pedestal, the steel plate and the grout material (mortar, resin, etc.) between the concrete pedestals are intimately bonded and strengthened.

[Brief description of drawings]

FIG. 1 is a schematic view of two facing members for forming a tubular article made of the steel sheet of the present invention.

FIG. 2 is a plan view of a tubular object, which is formed of steel plates connected to each other by the method of the present invention, located around a concrete pedestal.

FIG. 3 is a cross-sectional view showing the inside of the joined steel plates at the portions indicated by arrows 3 and 3 ′ in FIG.

FIG. 4 is a cross-sectional view showing a preferable cross-sectional shape of the protrusion and the connecting member in the portions indicated by 4 and 4 ′ in FIG.

5 is a cross-sectional view showing another cross-sectional shape of the protrusion and the connecting member in the portions indicated by 5 and 5'in FIG.

6 is a cross-sectional view showing another cross-sectional shape of the protrusion and the connecting member in the portion indicated by 6 and 6'in FIG.

FIG. 7 shows a case where the seam portion is at a corner portion of a quadrangle,
Sectional drawing which shows the cross-sectional shape of a protrusion part and a connection member.

Claims (3)

[Claims] 1. A method of reinforcing a periphery of a concrete pedestal with a steel plate member connecting article having a straight seam portion, wherein a projection having an engaging surface with a cross section always having the same shape in the longitudinal direction is formed by the straight line. Provided inside the steel plate member along the seam portion, at each arbitrary position of the seam portion of the steel plate member, a window having a length wider than both widths of the protruding portions adjacent to each other in a connected state is formed. At least one notch is provided per seam, and a plurality of the steel plate members are located at positions to be connected around the concrete stilt at a necessary distance from the wall surface of the concrete stilt. A respective engagement surface having a length that is not too long to be inserted through the window compared to the length of the window and a width that is narrower than the width of the window, and that engages with both of the adjacent protrusions. One of the connecting members that have A fluid material such as mortar that is inserted through the window onto the adjacent protrusions while engaging the engaging surfaces with each other, and hardens the gap between the wall surface of the concrete pedestal and the steel plate member. And filling the flowable material before or after filling the window, if necessary, by welding an iron plate or the like. 2. A cross section of a steel plate member connection is a quadrangle corresponding to a cross section of a concrete pedestal, a straight seam portion is present vertically at the center of two opposite sides of the quadrangle, and the window is at a low position. The method according to claim 1, wherein a large number of the connecting members are used. 3. A tubular article-forming member formed of a steel plate for reinforcing concrete pedestals, wherein the tubular article-forming member has 1) a cross section that can cover the periphery of the columnar article. 2) has a straight seam portion, 3) has a protrusion that is provided inside along the straight seam portion, and has a cross-section always having the same shape in the longitudinal direction, and ) At least one cutout portion is provided at each arbitrary position of the straight seam portion of the steel plate member, provided that the projection portion forms another tubular object by meshing with the connecting member. And a notch portion for connecting with another member for forming a tubular member at the straight seam portion, the width of the protrusion and the connecting portion Dimensioned to form a window wider than the width of the member and of sufficient length to aid in insertion of the connecting member That, members, wherein more.