JPS5827992B2 - Mortar and concrete spraying method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for spraying mortar and concrete.

With the improvement of tunnel construction methods and the development of ground support technology using Anchor Pol I, a method of spraying mortar or concrete onto the surface of excavated ground has come to be frequently used in recent years.

Spraying methods conventionally used are broadly divided into dry spraying methods and wet spraying methods, each of which has advantages and disadvantages.

The dry spraying method transports dry mixed cement and sand or cement, sand and coarse aggregate using compressed air, and sprays the mixture with pressurized water near the discharge nozzle. This method involves adding water and wet-mixing cement and sand, or cement, sand, and coarse aggregate, and transporting them using a squeeze ponzo, etc., and blowing them with compressed air, etc. near the discharge point 'J'.

Wet spraying is superior to dry spraying, but compared to dry spraying, wet spraying requires shorter transportation distances, requires larger machinery, and is more expensive due to construction costs. In most cases, dry blowing machines are used.

However, the dry spraying method has major drawbacks, such as a lot of dust and a lot of sleeve-splashing.
, C. A semi-wet spraying method using concrete 5 is beginning to be used.

Figure 1 is an example of a flow diagram showing the S, E, C blowing concrete method.

In this method, water W1 and cement C are added to a part of sand S whose water content has been adjusted using a sand controller i (thus, water W1 and cement C are mixed in a mixer, water W2 and admixture material Ad are further added to this, S, E , C mortar is made and transported by a pump to a mixing device near the discharge port, while the remaining sand is kneaded with gravel G, and the admixture Ad is added to this to make dry mixed aggregate. In this method, the material is sent to a mixing device using a dry sprayer, mixed with S, E, and C mortars, and then sprayed.

This method eliminates dust and reduces splashing, but it requires a sand controller to adjust the moisture content of the sand, and while the S, E, and C mortars are pumped to the mixing device near the discharge port, the dry The equipment became very complicated, as the mixed aggregate had to be sent to the mixing device using a dry spraying device, and the most important feature of the dry spraying method, which was that the equipment was compact and simple, was lost. The wet spraying method is more efficient and economical.

The present invention has been made to solve the above problems, and uses a dry spraying device to achieve efficient spraying without dust and with little splashing, which covers the shortcomings of the conventional dry spraying method. It provides a construction method.

The present invention will be explained below based on the embodiment shown in FIG.

FIG. 2 shows the flow of the spraying method according to the present invention.

First, water W1 equivalent to 5 to 15% of the sand weight is added to the air-dried sand SD, and the mixture is mixed using a concrete spraying method, and then cement c1, which is approximately 50% of the designed amount, is added and further mixed. Knead.

Next, this poorly blended mortar is transferred to a rotating plate or a swinging type granulator, and while granulating, the remaining half of the cement C2 is sprinkled from the top to produce a strong and uniform pellet-like mortar.

This pelleted mortar is transferred by a dry spraying machine,
The design mix remaining amount of water W after dissolving the quick setting agent Ac near Idehi
Spray while adding 2.

This is the mortar spraying method according to the invention.

In addition, after mixing this pelleted mortar with coarse aggregate in a concrete mixer, it is transferred to a dry spraying device.
Design mixture remaining amount of water W after dissolving the quick-setting material Ac near the discharge port
If you spray while adding 2, it becomes a concrete spraying method.

According to the present invention, mortar with a very low water content is granulated into uniform and solid pellets by the pelletizing machine, so it can be used as pellet mortar alone or as a mixture with coarse aggregate. Also, it can be easily transported over long distances using a dry spraying machine, and there is no possibility of dust being trapped near the dry spraying machine as in the conventional dry method.

In addition, the mortar granulated into pellets is easily mixed with the remaining amount of water in the design mix added at the discharge section, so there is no need for a mixer and no separation of the sprayed material occurs, so the amount of rebound is small. It has the advantage of being very small.

In other words, the present invention is an efficient concrete or mortar spraying method that eliminates the drawbacks of dry spraying methods and takes advantage of their advantages, and is a method that eliminates the drawbacks of dry spraying methods and makes the most of their advantages. This spraying method is much more economical and has good workability compared to the semi-wet spraying method of et al.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing a method for spraying S, E, and C mortars, and FIG. 2 is a flowchart showing a method for spraying according to the present invention. S, SD...°...°Sand, Wl, W2...°Water, C, CI. C2... Cement, G... Gravel, Ad
...Admixture material, AC...Quick setting material.

Claims (1)

[Claims] 1. 5 to 15% of the sand weight in air-dried washed concrete sand.
After adding and kneading water equivalent to 1.0% of the designed amount, approximately 1. /2 cement was added and further kneaded,
Transfer this mortar to a dotenura or rocking type granulator, and while giving it rotation or rocking motion, sprinkle the remaining 1/2 of the cement of the 3V mixture to hold the mortar in a pellet shape. This pellet-shaped mortar is then transported through the pipe using a dry spraying device, mixed with the remaining amount of water in the design mix in which the quick-setting agent has been dissolved near the discharge port, and then sprayed onto the target object. Mortar and conch featuring the following! Spraying method of J-1-. 2 Second wheel on air-dried concrete washing sand: ■: 5~
After adding water equivalent to 15% and kneading, approximately 1/2 of the designed amount of cement is added and further kneaded, and this mortar is transferred to a rotary or rocking granulator. Then, while rotating or rocking motion Lj, sprinkle the remaining 1/2 of the designed amount of cement to granulate the mortar into a beretsu I shape, and then add the designed amount of cement to this pelleted mortar. Coarse aggregate is mixed, transferred into the pipe by a dry spraying device, and then sprayed onto the object near the leaf outlet with 1 liter of water mixed with the designed mix remaining amount of water in which the quick-setting agent has been dissolved. A mortar and concrete spraying method characterized by: