JPH0420442B2 - - Google Patents

Description

Claim 1: A method for forming a roadway protection wall having a duct, wherein a first frusto-conically shaped mold plug is placed in a concrete formwork, the first plug having a lower end. A second frusto-conically shaped mold plug having an edge portion is placed in the concrete formwork, said second plug being disposed co-linear with a lower edge portion of the first plug. having a lower edge portion, the first and second mold plugs are placed end-to-end to form a continuous mold for the duct, casting concrete into the concrete formwork, and curing the concrete. and removing the first and second mold plugs from the hardened concrete.

2 the first and second mold plugs are arranged parallel to the base of the formwork and aligned to form a duct having a straight lower portion extending between opposite ends of the protective wall; The method according to claim 1.

3. a projection is formed at the first end of the protective wall section, and the projection is configured such that a plurality of such protective wall sections are connected end-to-end to form a continuous protective wall. 2. The method of claim 1, further comprising the step of forming a corresponding recess in the other end of the guard wall.

4. The method of claim 1, further comprising the step of forming a drain in the side of the guard wall so that liquid can communicate between the side of the guard wall and the duct.

5. Generally formed as an elongated structure with a duct, the duct being formed having a first portion and a second portion, the first portion extending gradually from the first end to the central portion of the protective wall portion. the first portion of the duct further having a lower edge portion and the second portion having a narrowing cross-section;
The protective wall section is formed with a cross section that gradually narrows from the second end to the central part, and the second part of the duct is arranged in line with the lower edge of the first part of the duct. further comprising a lower edge portion,
The first and second portions are interconnected to form a continuous duct.

6. The lower edge portions of the first and second portions of the duct are parallel to the base of the protective wall, and
Claim 5 extends from the end of the claim 5 to the second end.
Protective walls for roadways as described in Section 1.

7. a base having a substantially planar lower surface, a tapered intermediate portion extending from the base, an upright portion extending from the intermediate portion, and a duct formed in the base, the duct comprising:
comprising a first portion and a second portion, the first and second portions tapering from the first and second ends of the protective wall portion toward the central portion; The lower edge portions of the duct sections are located on the same line with each other as roadway protection walls.

8. A guard wall according to claim 7, wherein the first and second portions are interconnected to form a continuous linear section extending from the first end to the second end of the guard wall.

9. A guard wall according to claim 8, wherein the first and second portions are frustoconical in shape.

10. The guard wall of claim 8, wherein the first and second portions are interconnected to form a continuous linear section extending from the first end to the second end of the guard wall.

BACKGROUND OF THE INVENTION This invention relates generally to protective walls or separation members suitable for blocking or separating roadways, and in particular to internal ducts and passageways for drainage and cables, such as electrical cables or telephone lines. The present invention relates to a protective wall with conduits for cables and to a method of constructing such a protective wall.

It has been conventional practice to use protective barriers to separate oncoming traffic lanes. Such barriers may be either permanently installed in medians between lanes or temporarily installed at specific locations, such as on the roadway and to divert traffic away from construction sites adjacent to the roadway. be. The barrier prevents motor vehicles from crossing into the roadway of traffic in the opposite direction, thus preventing head-on collisions. Typically, such barriers include a plurality of reinforced concrete sections placed end-to-end to extend a desired length, which may range from several feet to many miles.
Some guard walls include coupling means for securing adjacent ends together to form a continuous rigid structure.

Such barriers typically include a base portion having a generally rectangular or trapezoidal cross section, a tapered intermediate portion, and an upright portion that may be tapered. The base typically rests on or is embedded in the median between lanes. The lowest edge of the base is generally the widest part of the guard wall. The intermediate section tapers from the widest point at the top edge of the base to the widest point at the bottom edge of the upright section.

Although these traditional barriers have been successful in preventing vehicles from crossing from one lane to another, low points in the roadway collect water, waste rock, and other foreign matter, and We have run into problems that arise primarily from the fact that undesirable accidents occur to vehicle drivers due to the collected materials. Conventional practice is to provide external drainage systems such as open channels, grooved surfaces, etc. to direct water away from the roadway surface. Such practices have not been particularly successful due to the fact that there are still puddles and exposed water as it takes time to drain. Also, conventional barriers are not designed to accommodate electrical cabling, pipes, or other auxiliary equipment.

U.S. Pat. No. 4,105,353, issued August 8, 1978, to Bork et al. A protective wall having an internal drainage duct is disclosed. The duct is suitable for use in a drainage system for passing water. Both ducts and passageways are suitable for carrying telephone lines, electrical wires, and the like. When used in a drainage system, the duct has side openings extending to the external surface of the protective wall to allow water to flow into the duct.
The guard wall has a male end and a female end such that an interconnected guard wall line is formed.

The barrier disclosed in U.S. Pat. No. 4,105,353 prevents vehicles from crossing oncoming lanes of traffic;
and is fully functional to provide a conduit or cable for drainage. However, significant problems are encountered when producing such protective walls. The duct is cylindrical, which means that a cylindrical mold must be incorporated into the formwork used for molding and curing the concrete forming the protective wall.
To maintain its shape while unsupported,
After the concrete is fully cast and hardened,
The cylindrical mold must be recovered from the concrete, leaving a cylindrical passage or duct. Even if oil or other suitable substance is coated on the external surface of the cylindrical mold before pouring the concrete, it is difficult to remove the mold due to friction between the mold and the surrounding concrete. extremely difficult. Therefore, removing the mold from the concrete is time consuming and expensive, resulting in a loss of productivity of workers and equipment. An alternative method for removing the mold is to incorporate a pipe of the desired length and diameter into the protective wall section. Since modern roadway configurations require a large number of protection wall sections, which should be manufactured as economically as possible, the incorporation of pipes into the protection wall is generally a step away from the protection wall. It is not considered a clearly economical alternative method for removing.

Therefore, this technology includes an improved roadway protection wall, and a longitudinal mold that is conveniently and easily removed from the protection wall after the concrete has sufficiently cured to allow the mold to be removed. A configuration method that provides for ducting is required.

SUMMARY OF THE INVENTION The present invention overcomes the problems associated with fabricating roadway barriers with ducts or conduits. The method of the invention uses a pair of tapered mold plugs, each approximately half the length of the guard wall.
The mold plugs are joined together, forming the central portion of the duct. Significant frictional forces are only experienced during the first movement during retrieval of the mold plug from the guard wall.

The shaped plug is preferably frustoconical;
Alternatively, the mold plug is formed in such a way that only the upper part of the duct has a narrowing taper from the end of the protective wall towards the center, in order to provide the duct with a flat and horizontal bottom. In order to form a horizontal bottom in the duct using a frusto-conical mold plug, the narrower end of the mold plug connects to provide a continuous mold so that concrete does not enter the area where the duct is. It must be formed like this.

This invention is more economically constructed than previous protection walls, while performing the same functions as previous protection walls, i.e. safely and effectively separating traffic lanes, while also being useful for drainage or for passing cables. Provide a protective wall for installing ducts.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a central protective wall of precast concrete according to the invention.

FIG. 2 is a partial cross-sectional view of the guard wall of FIG. 1 showing the ducts and drains;

FIG. 3 is a cross-sectional view taken along line 3--3 in FIG.

Figure 4 shows details of the joints of the protective wall.
2 is a cross-sectional view taken along line 4-4 of FIG. 1. FIG.

5 is a perspective view of a mold plug used to form a drain in the guard wall of FIG. 1; FIG.

6 is a perspective view showing details of one interior end of the mold plug of FIG. 5; FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, the guard wall section 10 includes a base 12, a midfoot section 14, and an upright section 16. The base 12, midfoot 14 and upright 16 are preferably integrally formed, but are referred to as separate parts for ease of explanation only. Guard wall 10 further includes a protrusion 18 at end 20 and a corresponding recess 22 , duct 26 , and a plurality of drain holes 28 at opposite end 24 .

Referring to FIG. 2, duct 26 preferably has a bottom surface 30 that is parallel to the longitudinal axis of base 12, such that base 12 and bottom 30 of duct 26 are at the same angle with respect to the horizontal. Take.
The duct 26 has a pair of sections 32 that are mirror images of each other.
and 34.

The upper parts 32 and 34 are connected to the bottom part 3 of the duct 26.
upper edges 36 and 3 tapered in the direction of 0;
8, the duct 26 is therefore narrower at the central portion 40 where the portions 32 and 34 meet than at the ends 20 and 24. , the portion 32 has an opening 42 at the end 22 of the protective wall 10. The opening 42 is located in the central portion 40 of the duct 26 in the portion 32.
has a larger cross-sectional area than the ends of. Similarly, portion 34 has an opening 44 at end 24 . Opening 42
and 44 are of substantially the same dimensions, and opening 4
2 and 44 are the protrusion 46 extending from the end 20 around the aperture 20 and the recess 48 extending into the end 24. The protective wall part 10 is
When connected to an end similar to end 24 of another guard wall (not shown), protrusion 46
It fits into a similar recess as 8.

Referring to FIGS. 1 and 4, opening 42,
44 are a male key 52 and a female key 5, respectively.
Contains 4. The male key 52 and the female key 54 are
Any configuration suitable for interconnecting a pair of end-to-end guards, such as guard wall 10, may be used. As shown in FIG. 1, male key 52 and female key 54 are octagonal in cross section, with the sides of male key 52 being slightly smaller than the sides of female key 54. Male key 52 and female key 5
The dimensions of the 4 sides are such that the male key 52 can easily pass through the female key, as shown in FIG.
When the guard walls 10 and 60 are suitably connected to form the joint 57, the end 56 of the male key 52 abuts the end 58 of the second guard wall 60. When surfaces 56 and 58 abut each other, male key 52 has a pair of surfaces 62 and 58 parallel to and slightly spaced apart from a pair of corresponding surfaces 66 and 68 on female key 54. It has 64. A suitable sealant (not shown) can be applied to surface 6.
2, 64 and surfaces 66, 68 to prevent moisture from flowing to or from the joint 57 between the protective walls 10 and 60.

1, 2 and 3 illustrate details of the drain 28. As shown in FIGS. 1 and 2, the drain 28 includes a generally rectangular opening 70.
A rectangular opening 70 leads to a duct 72, as best shown in FIG. Duct 7
2 intersect the duct 26 such that water flows through the opening 70 and the duct 72 into the duct 26. Although the barrier 10 is shown as having two drain ports 28, it may incorporate any desired number of similar drain ports.

The preferred method of forming barrier 10 is to attach a pair of tapered mold plugs 76 and 78 to conventional concrete formwork. The mold plugs 76 and 78 are frustoconical as shown in FIG. 5, but may also be trapezoidal in cross-section with a lower edge forming the desired flat bottom portion of the duct 26. The preferred embodiment thus provides a straight line with no low points where water can collect and stagnant.
It is an object of the present invention to provide a method for forming protective walls that are placed end-to-end for incorporating horizontal ducts.

If mold plugs 76 and 78 are frustoconical, mold plugs 76 and 78 must have surfaces 80 and 82 formed at their smaller ends, respectively, with surfaces 80 and 82 mating together. to form a continuous mold. The taper of the mold plug is typically only about 1-3 inches in diameter and 10 feet long. The duct 26 therefore has only a slight deviation from the cylindrical duct (not shown) incorporated into the previous protective wall.

In order to form a smooth internal surface on the duct 26,
Ends 80 and 82 must be formed to fit snugly together. As best shown in FIG. 6, the end 80 of the mold plug 76 is
Generally flat, making a small acute angle to the vertical. Each mold plug 76 and 78 has a second
, with the second ends 84 and 86 being perpendicular to the longitudinal axis. Therefore, the end 82 of the mold plug 78 must be formed to abut the end 80 of the mold plug 76, so there is no gap therebetween.

The mold plugs 76 and 78 are tapered to facilitate their removal from the concrete barrier 10. Unlike a cylindrical mold plug, which experiences substantial frictional resistance to retrieval along its entire length, it is only during the initial movement of the mold plug that significant resistance is encountered.