JP2000355920A - Surface irregularity molding method for cast-in-place porous concrete, and its molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the surface irregularity molding method for cast-in-place porous concrete and its molding die, by which an irregular shape can be molded effectively on a cast-in-place porous concrete surface as the revetment of a river or the like. SOLUTION: Porous concrete 11 is placed on a ground surface 10 such as the bank slope-face or the like of a river in desired thickness, the surface irregularity molding die 1 in which a projecting mold member 3 for molding a recessed section is held to a netty material 2 having flexibility is held at a regular interval is laid downwards on the surface of porous concrete 11 before porous concrete cures, a style is raised by pushing the projecting mold member 3 to the porous concrete surface 11 by pushing from the surface of the molding die 1, and the molding die 1 is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast-in-place porous concrete for forming irregularities on a surface of a porous concrete when installing a porous concrete covering for protecting a dike slope of a river and promoting greening. The present invention relates to a method for forming surface irregularities and a molding die thereof.

[0002]

2. Description of the Related Art In recent years, "creation of rivers without concrete"
Or, with the aim of "creating a river where concrete cannot be seen", the creation of a multi-natural river is being actively promoted throughout the country. Against this background, the use of porous concrete, which allows plants to grow on the seawall concrete itself, has been increasing as a river bank protection method.

[0003] Porous concrete refers to a porous concrete having a continuous or independent void structure or a large amount of these two types of void structures. In many cases, a binder such as mortar is mixed with coarse aggregate such as crushed stone. Are formed by binding the surfaces of the coarse aggregates to each other while covering the surfaces with the binder.

[0004] When such porous concrete is used for revetment of rivers, the continuous voids inside allow free passage of water and air, so that the roots of plants penetrate the porous concrete and take root on the embankment. Vegetation is possible on the revetment. In porous concrete revetment, plants grow and are covered with greenery, so that they can have a space in which living things can live. It has the effect of accumulating sediment suspended in it and can promote the regeneration of nature.

At present, there are two types of revetment method using porous concrete: a method of laying a porous concrete block and a method of constructing porous concrete by casting in place. In the method of casting in place, a backhoe bucket is used. It is used for surface molding, and after pouring porous concrete on the embankment surface, the surface is pressed and pressed by the bucket for about 10 seconds to thereby flatten the surface.

On the other hand, when growing a plant on porous concrete, it is necessary that the space is filled with a filler such as soil. In the case of rapid greening, it is necessary to fill the voids with a filler and cover the surface with a covering material. There are two types of filling: artificial filling and natural filling and waiting for natural filling. There are cases where waiting for natural filling of suspended earth and sand, and cases where waiting for filling of soil covering material on the surface layer by gradually flowing into voids due to rainfall or the like. Especially when it is not necessary to rush the greening, it is left unattended.In this case, it is affected by the flooding situation and the surrounding vegetation, but generally it takes more than several years until the plants can grow. It takes years.

[0007]

In the above-mentioned conventional method for finishing a porous concrete surface by casting in place,
Undulation can be applied to the entire surface, but the finished surface must be a flat finished surface.

In such a conventional porous concrete revetment, when left in a natural state, the surface is uneven as a result of the aggregate, but the surface is flat as a whole. The flow velocity of the water is hardly reduced, and it is difficult for the suspended sediment in the flowing water to be filled in the voids. Further, even if the soil is on the surface of the porous concrete, there are few portions where the soil is caught, so that the soil is easily washed away by running water and vegetation is hardly fixed. In addition, it is difficult to fill the gap. Further, there is a problem that a person is liable to slip when walking and is difficult to get close to.

The present invention has been made in view of such conventional problems,
An object of the present invention is to provide a method for forming a surface irregularity of a cast-in-place porous concrete capable of effectively forming a concave-convex shape on a surface of a porous concrete cast in place for revetment of a river, and a mold for the same.

[0010]

The feature of the method of the present invention for solving the above-mentioned conventional problems and achieving the intended purpose is that porous concrete is desirably used on the ground surface such as a dike slope of a river. A surface unevenness forming die in which a convex member for forming a concave portion is held at a predetermined interval on a flexible mesh material on the porous concrete surface before the hardening is completed after being cast to a thickness of, Laying the convex member downward,
The object is to press the surface of the mold and press the convex member into the surface of the porous concrete to form a mold, and then remove the mold.

It is preferable that after laying the surface irregularity forming die on the porous concrete surface, the convex member is pressed while being vibrated, whereby the pressing of the convex member and the compaction of the porous concrete are simultaneously performed.

A feature of the molding die according to the present invention resides in that a convex member for molding a concave portion is held at a predetermined interval by a flexible mesh material.

The net-like material is formed by holding a net-like material obtained by knitting a band-like material vertically and horizontally, and forming the net-like material into a square shape, and forming the net-like material on one of two opposing sides. A rod-shaped material to which the hanging material is fixed is fixed, and the work of setting and removing the surface unevenness forming die is performed by lifting with the hanging material, and the ends of the mesh material are attached to the other two sides facing each other. It is preferable to use a surface unevenness forming die to which a reinforcing member composed of a large number of short rods connected in a freely bendable manner is fixed.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

FIGS. 1 and 2 show an example of a surface unevenness forming die used in the present invention. This forming die 1 is provided on one side surface of a flexible rectangular mesh material 2 with a convex portion for forming a concave portion. Are held at regular intervals.

The mesh member 2 has bar members 4 and 4 fixed to one of two opposing sides, and a suspending member 5 made of a wire is attached to each of the bar members. It is designed to be lifted with the whole being expanded.

Further, the other two opposing ones of the mesh member 2 are opposed to each other.
Reinforcing members 7, 7 in which short bar members 6, 6,... Are connected to each other in a freely bendable manner are fixed to the sides, and both edges are formed so that the entire molding die 1 can be folded with the bar member 4 as a core. Has been reinforced.

As the net material 2, besides a wire net, a flexible net using fibers made of an organic or inorganic material can be used, and as shown in FIG. 3, band members 8, 8 made of cloth or synthetic resin. .. Can be used by arranging them vertically and horizontally at an interval. In this case, the band material 8,
8 is preferably about 3 to 10 cm. The size of the mesh is appropriately selected according to the shape and size of the convex member 3 to be fixed.

As the material of the convex member 3, various materials such as metal such as wood, paper and iron, rubber, glass, concrete, foamed resin and other synthetic resins, and a combination of these materials can be used. In addition, the shape shown in FIGS. 1 and 2 is a trapezoidal cross section in which the plane is rectangular, that is, a trapezoidal pyramid, a rectangular cross section in the long side direction in which the plane is rectangular, and a triangular cross section in the short side direction. 4 and 5, truncated cone shape, as shown in FIG. 6, triangular truncated pyramid shape, other shapes such as elliptical shape, waveform, zigzag shape, combination of straight lines and curves, etc. And various shapes can be used. In addition, the convex member 3 preferably has a trapezoidal cross section with a thin protruding end side. This improves the press-in performance at the time of press-fitting, which will be described later, and also improves the releasability after molding.

Next, the molding of the surface of the porous concrete using the above-mentioned molding die 1 will be described. As shown in FIG. 15-30c
m, and the surface is roughly finished roughly flat. Next, before the porous concrete is hardened, the forming die 1 is lifted using a backhoe or a crane, and is placed on the surface of the poured porous concrete 11 with the convex member 3 facing downward.

Next, as shown in FIG. 8, the vibrating plate 12 and / or a vibrator is installed on the method-forming bucket of the backhoe from above the mesh member 2, and the convex member 3 is used.
Is pressed into the surface of the porous concrete 11 and the porous concrete 11 is vibrated and compacted.

After the press-fitting of the convex member 3 is completed over the entire area of the single molding die 1 as described above, as shown in FIG. 9, the hanging member 5 is moved by using a working machine such as a backhoe or a crane. The mold 1 is removed. Thereby, each convex member 3 is provided on the surface of the porous concrete 11.
Is formed.

This operation is repeated every time the porous concrete is cast to form an irregular shape on the surface of the porous concrete.

The arrangement of the recesses 13, that is, the arrangement of the convex members, is adjusted by adjusting the interval between the recesses so that the speed of the flowing water in the river is reduced and the suspended sediment in the flowing water is easily settled and deposited. Is preferred. The size of the mesh material 2 is as follows.
It is preferable that the area is such that the cast-in-place porous concrete can be transported and cast at one time, or the same size as a section divided into squares by vertical and horizontal joints.

EXAMPLE A coarse aggregate (No. 5 crushed stone), a fine aggregate (fine sand), cement and a special admixture were charged into a forced twin-screw mixer in accordance with the amounts shown in Table 1, and kneaded for about 30 seconds. did. Thereafter, water was added and the mixture was fully kneaded for about 3 minutes to knead the porous concrete. After kneading, load it on a dump truck and
It was transported for about 0 minutes and was unloaded on a steel plate laid on a high riverbed.

The low-water revetment of the river is preliminarily formed with a backhoe at an inclination of 1: 2.0, and an average diameter of 0.2 mm is formed on the soil surface.
And a nonwoven fabric made of chemical fiber having a thickness of 10 mm was laid as a suction-preventing material. In addition, partitions were provided on the low-water revetment slopes at intervals of 5 m in width and 2 m in length by blanking boards to separate the slopes.

The porous concrete unloaded on the iron plate was laid down in a section on the slope with a backhoe method forming bucket to a thickness of 25 cm, lightly tightened, and temporarily formed.
Immediately thereafter, for each section, a molding die using the stamping member shown in FIGS. 1 and 2 (the stamping member used was one obtained by processing and applying wood, or one obtained by processing polypencoacetal resin, iron, rubber, or the like. ) Were installed, and vibration and pressure were applied while moving the diaphragm from above the net-like material, and vibration molding was performed until the pressing die was completely embedded in the porous concrete. Immediately after the molding, the mesh material was pulled up, the pressing mold was released, and a curing agent was sprayed to cure.

In the revetment of the porous concrete having the irregular shape on the surface formed in this way, the irregular shape can be neatly and regularly applied in a relatively large area (one section), and the landscape is excellent. In addition, in the revetment after completion, the revetment of porous concrete with an uneven surface made it less slippery when walking than a section with a flat surface due to the uneven shape, and anglers could safely approach the waterside.

Further, as for the seawall of porous concrete having an uneven surface and the seawater of the porous concrete having no flat surface, the observation of the state of mud accumulation and greening was continued. After the flooding, in each of the porous concrete sections with irregular shapes on the surface, sediment accumulated in the recesses around each section, and invasion and growth of surrounding plants were observed.

In the places where the plants grew, more sediment was deposited on the downstream side from the plants, and sediment was deposited not only on the concave parts but also on the convex parts.

On the other hand, in the porous concrete section having a flat surface, almost no sedimentation was observed, and no invasion and growth of surrounding plants were observed at all. From this fact, it can be seen that in the cast-in-place porous concrete, the unevenness is applied to the surface to promote the accumulation of sediment on the surface and to accelerate the invasion and growth (natural recovery) of surrounding plants.

During the observation period, even when the surface was processed into an uneven shape, no chipping or cracking of the porous concrete at the protruding portion was observed at all, and there was no difference in quality from the case of the flat surface. Table 1 Formulation of cast-in-place porous concrete (1 m ³ ) Coarse aggregate size No. 5 crushed stone Cement 300 kg Water 70 kg Fine aggregate 150 kg Coarse aggregate 1403 kg Special admixture 10 kg to 50 kg

[0033]

As described above, according to the present invention, by using the net-like material, it is possible to adapt to the shape of the revetment slope and to form it with a continuous undulation. It can be formed continuously from the shoulder, the slope, the bottom, and the fastening. Furthermore, the state of vibration compaction can be observed through a mesh, and a decrease in the porosity in the porous concrete due to excessive compaction can be visually prevented. Furthermore, by using a flexible net-like material, it is easy to push in and remove the mold from the edge of the molding die, thereby improving workability.

Further, by performing the pressing of the convex member of the molding die while oscillating, the compaction of the porous concrete can be performed at the same time.

Further, by comprising the mesh material, it is possible to prevent the mesh material from being embedded in the porous concrete at the time of the press-in operation, and it is possible to cleanly finish the surface of the porous concrete after demolding.

Further, by fixing a rod-shaped member having a hanging member fixed to two opposing sides of the net-like member, it becomes possible to handle the rod-shaped member in a state where the forming die is expanded by lifting the rod-shaped member, and to handle the porous concrete surface. Removal of the mold after installation and pushing is facilitated.

Further, by forming irregularities on the surface of the porous concrete as described above, the speed of flowing water is attenuated by the irregularities, and the sediment floating in the flowing water is settled and easily deposited. The soil and the soil are held by the unevenness, and the voids in the porous concrete are filled at an early stage even in a natural state, and as a result, the regeneration of nature can be promoted.

[Brief description of the drawings]

FIG. 1 is a plan view of an example of a mold used in the method of the present invention.

FIG. 2 is a partially enlarged sectional view of the same.

FIG. 3 is a partial plan view of another example of a mold used in the method of the present invention.

FIG. 4 is a plan view of still another example of a mold used in the method of the present invention.

FIG. 5 is a partial longitudinal sectional view of the same.

FIG. 6 is a plan view of still another example of a molding die used in the method of the present invention.

FIG. 7 is a cross-sectional view showing an installation state of a forming die in an execution example of the method of the present invention.

FIG. 8 is a cross-sectional view showing a state in which the convex member is pressed in the same.

FIG. 9 is a cross-sectional view showing a mold release state of the above.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 molding die 2 mesh material 3 convex member 4 rod material 5 hanging material 6 short bar material 7 reinforcing material 8 band material 10 slope 11 porous concrete 12 vibration plate 13 recess

Claims (6)

[Claims] 1. A method of forming a concave portion in a flexible net-like material on a surface of a porous concrete surface after pouring the porous concrete to a desired thickness on a ground surface such as a dike slope of a river and before the hardening is completed. A convex-concave mold holding a convex member for use at a predetermined interval is installed with the convex member facing downward, and pressed from the surface of the mold to place the convex member on the porous concrete surface. A method for forming irregularities on the surface of cast-in-place porous concrete, characterized in that the molding is performed by pushing in and then the molding die is removed. 2. The method according to claim 1, wherein after the surface irregularity forming die is laid on the porous concrete surface, the convex member is pressed while being vibrated, whereby the pressing of the convex member and the compaction of the porous concrete are simultaneously performed. The method for forming surface irregularities of the cast-in-place porous concrete described above. 3. An in-situ cast-in-place porous concrete mold comprising a flexible net-like material and convex members for forming concave portions held at predetermined intervals. 4. The mold according to claim 3, wherein the reticulated material comprises a reticulated material formed by knitting a belt-like material vertically and horizontally. 5. A net-like material is formed into a square shape, and rod-like materials each having a hanging material fixed thereto are fixed to one of two opposite sides thereof, and can be moved in an unfolded state by being lifted with the hanging material. The surface irregularity forming die of the cast-in-place porous concrete according to claim 3 or 4. 6. A cast-in-place porous member according to claim 3, wherein a reinforcing member comprising a plurality of short rods whose ends are foldably connected to each other is fixed to the other two opposite sides of the mesh member. Concavo-convex mold for concrete surface.