JPH011861A - Spraying method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention is used for spraying concrete or mortar in tunnel construction, cut slope construction, etc. to prevent weathering and stabilize the ground. The spraying is related to construction methods.

<Conventional technology> Conventionally, when constructing the ground around tunnels and slopes such as roads and railways, spraying methods with good mobility have been used without using formwork to prevent weathering and stabilize the ground. Equipment is often used to spray materials such as concrete or mortar onto the ground or slope.

However, during construction, the material is ejected from a nozzle using compressed air, and the speed of the material in the pipe is slower as it approaches the inner wall of the pipe, and in the injection state as it approaches the outer periphery. Small particles become more dispersed toward the outer periphery and scatter as mist-like dust, deteriorating the working environment.

On the other hand, the present applicant has proposed a construction method for spraying that injects a water film around the material to prevent the scattering of dust. This has already been proposed in Publication No. 57-473854.

<Problems to be Solved by the Invention> However, in the conventional spraying method, a large amount of water is sprayed onto the construction surface, and some of the mortar adhering to the slope surface is washed away.・There were problems such as an increase in cement ratio and a decrease in developed strength.

This invention was made by focusing on such conventional problems, and the spraying method injects shield-like bubbles around the material when the material is injected, thereby reliably reducing the scattering of dust. The purpose of this invention is to provide a spraying method that does not cause deterioration of the construction surface or decrease in strength of the material.

<Means for Solving the Problems> The spraying method according to the present invention is such that when spraying materials such as concrete, a foam nozzle that injects shield-shaped foam is provided around the nozzle, and the above spraying is performed by injecting foam from the nozzle. The material is covered with a shield-like foam ejected from the foam nozzle. Here, the shield-like bubbles include surfactant aqueous solutions, resin soaps,
Possible causes include protein bubbles. Further, the shield-shaped foam may be ejected from the inner periphery of the nozzle or from the outer periphery.

Function> The foam nozzle of the present invention injects shield-shaped foam into, for example, a cylinder during the spraying operation, and injects the material and its mist into the shield-shaped pond. It acts to trap dust, and by making some of this dust adhere to the shield-like bubbles, it effectively suppresses the scattering of the dust.

<Embodiment of the Invention> An embodiment of the invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram of the main parts showing the spraying method of this invention. In the figure, reference numeral 1 denotes a nozzle that injects concrete, mortar, etc., and the properly kneaded and hydrated spray material is pumped by a pump or the like. 2 is a foam nozzle installed on the outer periphery of the tip of the nozzle 1. An aqueous solution of a foaming agent is pumped into the foam nozzle 2 by a transfer pump, and this aqueous solution is converted into a shield-shaped foam 4 during injection. The above-mentioned spraying is injected around the material 3.

5 is a construction surface such as a tunnel wall or an embankment slope where construction is performed.

FIG. 2 is a perspective view showing the structure of the tip of the spray nozzle 1, which has a normal pipe structure. In addition, the foam nozzle 2 is separated from the material injection part 7 by a plurality of duct members 6 attached to the periphery of the nozzle 1, that is, the inner periphery of the nozzle end, and the inside of each of these duct members 6 is is in communication with a foaming material supply pipe 8 connected to the nozzle 1. The foam nozzle 2 injects the foaming agent aqueous solution supplied from the foaming material supply pipe 8 as a shield-shaped foam from its tip.
For spraying other than concrete and mortar, material 3 is injected from the material injection section 7.

FIG. 3 is a perspective view showing another embodiment of the structure of the tip of the spray nozzle 1. This is a foaming material that has a normal pipe structure, and a plurality of foam nozzles 9 (four in this case) are attached to the outer periphery of the nozzle 1 end, and an aqueous solution of foaming agent is supplied to each of these foam nozzles 9. It consists of a supply tube 10 connected in branches.

In order to spray the concrete or mortar material 3 onto the construction surface 5 using the nozzle 1, the concrete or mortar that has been appropriately kneaded and hydrated and is pumped by a pump or the like is sprayed. is injected from one end of the nozzle.

At the same time or somewhat earlier, an aqueous solution of the foaming agent is injected from the foam nozzle 2 or 9 through the foam supply pipe 8 or the foam tube 1°. Through each of these injections, a shield-shaped foam 4 made of foamed aqueous foaming agent is injected from the foam nozzle 2 or 9, and this shield-shaped foam 4 is sprayed onto the injected concrete or mortar. Surround the material 3. Therefore, during this spraying, the scattering of the atomized dust in the material 3 is suppressed by the shield-like foam 4, and the deterioration of the working environment due to this dust can be reduced. Further, a part of the atomized dust is sprayed onto the construction surface while being wrapped in the shield-like bubbles 4, and directly adheres to the sprayed mortar or the like.

Although not shown, the injection amount of the shield-shaped foam 4 and the spray material 3 can be adjusted arbitrarily by adjusting valves provided in the foaming material supply pipe 8 and the spray nozzle 1, respectively.・〈Effects of the Invention〉 As detailed above, according to the present invention, when spraying concrete or mortar, a foam nozzle that injects shield-shaped foam is provided at the periphery of the nozzle. In the above spraying, the material is injected from the nozzle.In the above spraying, the material is injected so as to be covered by the shield-like foam, so when the material is sprayed on the construction surface, the material is injected from the nozzle. Spraying can effectively suppress the scattering of atomized dust among the materials, and also make it easier for some of it to adhere to the construction surface, and as a result, it is possible to effectively prevent deterioration of the construction environment. Effects such as this can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory view showing the spraying method of the present invention, and FIGS. 2 and 3 are partially cutaway perspective views showing the tip structure of the spray nozzle and foam nozzle, respectively. 1. Spraying with nozzle, 2. Foam nozzle, 3. Spraying with material, 4. Shield-shaped foam.

Claims (1)

[Scope of Claims] 1) When the spray material is being injected from the spray nozzle, a shield-like shield is formed from the foam nozzle connected to the spray nozzle so as to surround the spray material being injected. A spraying method characterized by injecting foam. 2) The spraying method according to claim 1, wherein the shield-shaped foam is ejected from the inner periphery of the spray nozzle. 3) The spraying method according to claim 1, wherein the shield-shaped foam is ejected from the outer periphery of the spray nozzle.