JP2974654B2 - Construction method using mortar and concrete mixed with steel fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION

[0002] The present invention relates to a method of forming a slope using mortar or concrete.

[0003]

2. Description of the Related Art Moldings of mortar and concrete include a method frame to be constructed on a slope, a U-shaped groove, a mortar, a concrete building, a mortar, and a concrete road surface. In addition, as a method of applying mortar and concrete, a mortar and concrete spraying method, an in-situ frame method, a precast method, and the like are known. In the construction methods such as slopes, when using the spraying method, when the spraying site is far away, or because of its high adhesiveness to slopes with lots of rock, etc. It is increasingly used.

[0004]

Generally, mortar,
Concrete moldings are particularly rich in mortar with a high blending and high slump value, and concrete moldings have a problem that cracks are liable to be formed during curing shrinkage. The mortar and concrete spraying method has a problem in that the mortar and concrete sprayed in summer and winter, and especially on dry slopes, have cracks in the vertical and horizontal directions, resulting in poor strength mortar and concrete structures. . In the framing method, there is a problem that when mortar and concrete harden and shrink, there is a tendency for cracks to occur very frequently at the intersections of grid frames provided on the slopes, especially where cracks are formed at the upper part of the vertical beams, resulting in low-strength framing. Was.

When a mortar or concrete having a low slump value is used for the construction of mortar or concrete, especially when the slope is a dry bedrock, the sprayed mortar or concrete floats without adhering to the bedrock. There was a problem that a gap was formed between the slope and the mortar or concrete structure.

[0006] Generally, in the construction of mortar and concrete, in order to improve the strength of a molded product or a structure, a so-called rich mortar in which the mixing ratio of cement is increased by the mixing ratio of cement: sand or the like is used. Often. When constructing a structure such as a slope with a fluid such as a mortar having a rich blend and a high slump value, the distance between the compressor and the slope site tends to be long, and the mortar which is a fluid However, there is a problem that the concrete is separated in the pipe during the pumping, and is further clogged, so that the pumping pipe ruptures. That is, when using a long-distance fluid pumping device, even if cement, water, fine aggregate, etc. are mixed in advance, if the length of the pumping pipe exceeds 40 m, the fine bones are formed in the downstream pumping pipe after merging with air. Materials with a large unit volume, such as materials, are extruded first to receive more air pressure than water, etc. Materials with a small unit volume (or highly adhesive), such as cement, adhere to the inner wall of the pipe and collect. The phenomenon that it becomes an attachment appears. When the pressure becomes large and the pressure in the pressure feed pipe rises, a so-called air hammer occurs, and there is a problem that these masses of cement flow out at once.

[0007]

In order to solve these problems, a spiral shape made of a mortar or a concrete material having a high slump value and a rich mixture of a steel material having an expansion coefficient substantially equal to the expansion coefficient of the mortar or concrete is used. Steel fiber of length 15mm to 27mm, thickness 1.0m
A spiral rod having a width of about 2.5 mm is formed from a single flat bar having a width of about 2.5 mm to about 1.5 mm and a width of about 1.0 mm to 1.5 mm. The mortar, the fluid mixed with the adhesion enhancer for concrete, the air and the fluid are mixed using a fluid pumping device having an air fluid merging and pumping pipe, and the material separation of the fluid is performed. We propose a construction method using mortar and concrete mixed with steel-like fibers, characterized in that the mortar is mixed with steel-like fiber and is constructed by spraying it onto slopes while preventing it.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an embodiment of the present invention, and FIG. 1 is a partially sectional explanatory view of a mortar mixed with steel fibers and a concrete molding. FIG. 1 is an enlarged view of one spiral steel fiber. FIG. 2 is a front view, FIG. 3 is an explanatory diagram of a fluid pumping device used in the construction method of the present invention, and FIG. 3 is an explanatory diagram of a fluid pumping device of the fluid pumping device to an air fluid confluent pumping tube. This will be described with reference to FIG. 4, which is also a front cross-sectional view of the air-fluid merging and pressure-feeding pipe.

The mortar or concrete 10 containing steel fibers used in the embodiment of the present invention has a coefficient of expansion substantially equal to that of the mortar or concrete 100 in the mortar or concrete material 100 such as cement or sand. Spiral Shaped Steel Fiber 1 Made of Steel
01 and mortar, concrete adhesion enhancer 102
The mortar and the concrete fluid 10a are mixed and solidified and manufactured.

In this embodiment, the steel material having an expansion coefficient substantially equal to the expansion coefficient of the mortar or concrete material 100 is a spiral-shaped steel fiber 101 having a length of 1 mm.
5mm to 27mm, thickness 1.0mm to 1.5mm,
A flat bar with a width of 1.0 mm to 1.5 mm is formed into a spiral shape with a width of about 2.5 mm, and 80 kg to 100 kg is mixed with the mortar and concrete material 100 in an amount of 1 cubic meter. You. The mixture is further mixed with a mortar and a concrete adhesion enhancer 102 to form and manufacture.

Further, in this embodiment, the mortar and concrete material 100 have a high slump value in a rich composition with a high cement ratio. As the mortar and concrete adhesion enhancer 102, an alcohol-based emulsion, styrene butadiene rubber terrax, or the like is used. The mortar and concrete molding 10 are mixed with the above materials to form a mortar and a concrete fluid 10a, and the mortar and the concrete fluid 10a are sloped or walled by a spraying method, a precast method, a cast-in-place method or the like. Forming and repairing, reinforcement of concrete joints, etc.

Next, an embodiment of the present invention will be described in which a mortar or concrete mixed with steel fiber is used to construct a slope or the like. In this embodiment, the mortar to be used is a mortar to be used, and a fluid pumping device is used which pumps the concrete fluid 10a by several hundred meters and blows the mortar onto the slope, etc. , Mortar in concrete material 100,
A plurality of spirally shaped steel fibers 101 and mortar made of a steel material having an expansion coefficient substantially equal to the expansion coefficient of concrete, a mortar obtained by mixing a concrete adhesion enhancer 102, and a concrete fluid 10a are compressed air by a compressor 1. Is mixed with the mortar and the concrete fluid 10a in an air fluid confluent pressure feed pipe 32 provided in the middle of the fluid pressure feed path, and is fed by a fluid pressure feeder for preventing material separation of the fluid, and is sprayed on a slope or the like. Perform solidification.

A fluid pressure feeding device used in the method of constructing a slope will be described. The fluid pumping device includes an air compressor 1, a fluid pump 2, a pumping tube 3 including an air-fluid merging pumping tube 32, a fluid outlet 4, an air chamber 5, and the like. 6 is a slope. The pumping pipe 3 includes a compressor-side air pipe 30, a fluid pump pipe 31, an air-fluid merging pumping pipe 32, and a downstream pumping pipe 33. A fluid outlet 4 is provided at the tip of the pressure feed pipe 3. The downstream pressure feeding pipe 33 is a long-range blowing pipe 3 which is a flexible hose having a length of about 7 to 20 m at the downstream end.
3b and the long distance scattering tube 33a can be detachably changed according to the application. The long-range scattering tube 33a is 4-7
It consists of a straight pipe with a length of about m.

The compressor-side air pipe 30 has an upstream end connected to the air compressor 1 and a downstream end connected to a straight air main air compression pipe 34 of the air-fluid confluence feed pipe 32 through a compressed air hose connected to the upstream end. Become. An air valve 7 for pressure adjustment and a check valve 8 are provided at a connection portion with the main air compression pipe 34. 7a is a pressure gauge. The fluid pump pipe 31 has an upstream end connected to the fluid pump 2, and a downstream end connected to an upstream port of the fluid inlet pipe 37 of the air-fluid merging pump 32. An air chamber (pressure tank) 9 is provided in the middle of the fluid pump pipe 31. The air chamber 9 is provided with a lid 90 at an upper portion, and the lid 90 can be freely opened and closed for an operation such as cleaning. The air chamber 9 has an action of changing a waveform pressure generated from the fluid pressure pump 2 into a fluid such as mortar into a continuous stable pressure.

The air-fluid confluent pressure feed pipe 32 joins a straight main air compression pipe 34, a fluid feed pipe 37 that diagonally joins the main air compression pipe 34, and a fluid pipe 37 that diagonally joins the fluid feed pipe 37. A multi-branched pipe composed of a fluid air pipe 38 which flows. The main air compression pipe 34 is a cylindrical pipe having a straight shape and the outer diameter of the pipe does not change. The main air compression pipe 34 is connected to the check valve at the upstream inlet, and is connected to the downstream pressure feed pipe 33 at the downstream outlet. The main air compression pipe 34 has a first jet pipe 35 and a second jet pipe 36 provided therein.

The first jet pipe 35 is a partial conical pipe having a maximum diameter at the upstream inlet and a jet port having a minimum inner diameter at a position slightly upstream of the junction with the fluid feed pipe 37.
In this embodiment, the length is 300 mm, the maximum inner diameter is 50 mm,
The minimum inner diameter is 20 mm. The second jet pipe 36 is a partially conical pipe having a maximum diameter at a position slightly downstream from a position where the second jet pipe 36 merges with the fluid supply pipe 37 and a discharge port having a minimum diameter at the downstream outlet. In this embodiment, the length is 250 mm, the maximum inner diameter is 65 mm, and the minimum inner diameter is 42 mm. Second jet tube 4
6 is shorter and has a larger inner diameter than the first jet tube 45.

The fluid feed pipe 37 has a straight upstream portion,
The downstream portion is a curved cylindrical tube, and merges obliquely in the straight air main air compression tube 34 in the traveling direction of air. The fluid feed pipe 37 is bent while gradually reducing its diameter until it joins the main air compression pipe 34 at the downstream portion thereof. The fluid air pipe 38 joins the fluid inlet pipe 37 at an upstream position from the junction with the main air compression pipe 34, that is, at a curved tubular portion which is a downstream portion, obliquely in the traveling direction of the fluid. .

In this embodiment, the fluid air pipe 38 comprises a downstream fluid air pipe 38a and an upstream fluid air pipe 3a.
8b, and the downstream fluid air pipe 38a
Is provided with a relatively large inner diameter. The two fluid air pipes 38a and 38b are connected to the air compressor 1, respectively. The fluid air pipe 38 may be a single fluid pipe, or may be two or more fluid air pipes. The greater the number, the greater the effect of pushing out the fluid to the downstream side.

The inner diameter of the fluid air pipe 38 provided further downstream is made thicker. In this embodiment, the downstream fluid air pipe 38a is about 16 mm, and the upstream fluid air pipe 38b is about 12 mm. The inside diameter of the fluid air pipe 38 is smaller than that of the fluid inlet pipe 37. Each of the fluid air pipes 38a and 38b is provided with an air tank 38c for pressure adjustment, an air valve 38d for pressure adjustment, and a pressure gauge 38e on the way. The main air compression pipe 34 is connected to the compressor side air pipe 30 communicating with the air compressor 1 at the upstream inlet, and the fluid such as mortar from the fluid pressure pump side pipe 31 communicating with the fluid pressure pump 2 is supplied. It is a multi-branched tube that joins. Air fluid confluent pressure feed pipe 3
The method of constructing the slope 6 by using the fluid pumping device having the step 2 will be described.

First, a material 100 such as cement, water and fine aggregate, a steel fiber 101, a mortar adhesion enhancer 102 (styrene,
A mortar hardening rate retarder such as butadiene rubber latex or polyvinyl alcohol liquid) is mixed to prepare a mortar fluid 10a having a high blending ratio and a high slump value. In this embodiment, the mortar fluid 10a having a rich blend and a high slane value is rich with a high slump value of 18 cm or more. This high slump mortar fluid 1
Oa is sent directly to the tank or the like of the fluid pressure pump 2 to be fed.

When spraying mortar, concrete or the like on the slope 6, first, the air compressor 1 is operated to feed compressed air to the compressor-side air pipe 30 of the pressure feeding pipe 3. At about the same time, by operating the fluid pump 2, the fluid 10 a such as mortar or concrete is pumped through the fluid pump pipe 31, and air is pumped through the compressor-side air pipe 30. Are respectively fed to the air-fluid confluence and pressure-feeding pipe 32 and merged.

The air from the air compressor 1 passes through the compressor-side air pipe 30, enters the main air compression pipe 34 of the air-fluid merging / pumping pipe 32 from the upstream inlet, and enters the large-diameter inlet of the first jet pipe 35. . Here, the air is compressed to increase the pressure and speed, so that the jet port 35 of the first jet pipe 35
Injected from a. Jet port 35a of first jet tube 35
Is slightly upstream of the merging position of the fluid inlet pipe 37 of the air fluid merging and pressure feeding pipe 32, and the fluid 10a merging obliquely from the fluid inlet pipe 37 in the air traveling direction is
It mixes with air from the jet port 35 a of the first jet pipe 35 and subsequently enters the second jet pipe 36. The mixture of air fluids is further compressed by a second jet tube 36,
By increasing the pressure and speed, the jet port 36a of the second jet pipe 36 is increased.
Is ejected from the downstream pumping pipe 33 to the downstream pumping pipe 3 as it is.
3 is blown out from the fluid outlet 4 to the slope 6.

The mixture of the air fluid ejected from the second jet pipe 36 becomes small and stable aggregates due to the strong linear flow of air. At the confluence of the main air compression pipe 34 and the fluid feed pipe 37, the pressure of the first jet pipe 35 and the pressure of the second jet pipe 36 are backflow pressures (Pascal's principle).
As a result, pressure is applied to the fluid supply pipe 37, but due to the air pressure of the fluid air pipes 38a and 38b, the fluid 10a overcomes the backflow pressure and smoothly flows downstream. In addition, the fact that the diameter of the fluid feed pipe 37 is gradually reduced from the upstream side to the confluence position also reduces the backflow pressure and increases the flow rate of the fluid 1.
The ejection pressure is increased to 0a.

When the long distance scattering pipe 33a is connected to the downstream side outlet of the main air compression pipe 34, the downstream pressure feeding pipe 33 has the second jet pipe 36 because the long distance scattering pipe 33a is linear about 5 m. The mixture of the air fluid from the air is completely converted into small stable aggregates at a high speed, and the backflow pressure from the downstream pumping pipe 33 on the further downstream side is suppressed. Downstream pressure pipe 3
When 3 is changed to a straight long-distance scatter pipe 33a having a length of 5 to 7 m, the fluid 10a passing therethrough under pressure becomes an agglomerate, and has a high compressed air pressure by the same action as an air gun. And scatters from the exit of the long distance scattering tube 33a to a height (distance) of 15 to 20 m.

Thus, for example, the slope can be constructed even on a slope which cannot be approached due to a high risk of a crushed rock, a slope with weathered cracks, or the like. Furthermore, a high slump-like fluid 10
Because it is a, pour deep into the cracks in the ground
In addition, it enters into places that cannot be accommodated by low-slump mortar, such as the backside of boulders, crushed stones, small rock fragments, etc., and coats the sprayed adhesive layer that is integrated with the high strength ground.

[0026]

Thus, according to the construction method using cement or concrete containing steel fiber of the present invention, the mixed steel fiber becomes entangled like cotton at the time of hardening shrinkage after construction. In the gaps, fine aggregate, coarse aggregate, and cement are mixed, and furthermore, they are firmly bonded by a polyvinyl alcohol-based adhesive, which is an adhesion enhancer.
Since the expansion coefficient of the steel fiber is almost equal to the expansion coefficient of mortar and concrete, there is no crack in expansion or contraction of mortar or concrete.

Further, by spraying these mortars and concretes on mortar structures, concrete structures and cracked structures which have been deteriorated, the deterioration can be suppressed and the hardness can be improved. it can. In particular, by spraying the mortar and concrete of the present invention to the joint of mortar and concrete, the strength can be improved, which is effective.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional explanatory view of a mortar and a concrete molding mixed with a spiral steel fiber.

FIG. 2 is an enlarged front view of one spiral shaped steel fiber.

FIG. 3 is an explanatory view of a fluid pumping device.

FIG. 4 is an explanatory view from a fluid pressure pump to an air fluid confluence pressure pipe;

FIG. 5 is a front cross-sectional view of the air-fluid confluent pressure feed pipe of the present invention.

[Explanation of symbols]

Reference Signs List 10 Molded product such as mortar, concrete, etc. 10a Mortar, concrete fluid 100 Cement, sand, fine aggregate, etc. mortar, concrete material 101 One spiral shaped steel fiber 102 Mortar, concrete adhesion enhancer 1 Air compressor 2 Fluid pressure pump 3 Pressure pipe 30 Compressor side air pipe 31 Fluid pump pipe 32 Air fluid confluence pressure pipe 33 Downstream pressure pipe 33a Long distance scattering pipe 33b Long distance spraying pipe 34 Main air compression pipe 35 First jet pipe 35a First jet pipe jet port 36 Second jet pipe jet port 36a Second jet pipe jet port 37 Fluid feed pipe 38 Fluid air pipe 38a, 38b Fluid air pipe 38c Air tank (for pressure adjustment) 38d Air valve (for pressure adjustment) ) 38e Pressure gauge 4 Fluid outlet 5 Stirrer Cement or mixer truck 6 slopes 7 air valve 8 check valve 9 air chamber

────────────────────────────────────────────────── (5) Continuation of the front page (51) Int.Cl. ⁶ identification code FI C04B 24:26 14:48) (56) References JP-A-58-9866 (JP, A) JP-A-1-122942 (JP) JP-A-57-33911 (JP, A) JP-A-54-122330 (JP, A) JP-A-53-23327 (JP, A) JP-A-59-196114 (JP, A) 7-309652 (JP, A) JP-A-7-118079 (JP, A) JP-A-54-120631 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C04B 28/02 -28/08 C04B 14/48 C04B 24:26 C04B 14:48

Claims (1)

(57) [Claims] 1. A spiral shaped steel fiber made of a steel material having a coefficient of expansion substantially equal to that of mortar or concrete in a mortar or concrete material having a high slump value in a rich composition and having a length of 15 mm to 27 mm. , Thickness 1.0 mm to 1.5 mm, width 1.0 mm to 1.5
mm is a spiral rod with a width of about 2.5 mm. The mortar and concrete material are mixed in an amount of 80 kg to 100 kg per cubic meter. Using a fluid-feeding device with an air-fluid converging / pumping pipe where the air and the fluid merge, the mixed fluid is pumped while preventing material separation of the fluid, and sprayed onto the slope etc. Mortar mixed with steel-like fibers, characterized in that
Construction method using concrete.