Wet spraying manipulator is a commonly used equipment in modern engineering, which is used to spray concrete onto the rock surface to form a tight and solid bonding layer. This article will discuss the spraying skills and related methods of wet spraying manipulator in detail to ensure the quality and effect of sprayed concrete.
1. Spraying skills of wet spraying manipulator
In the wet spraying process, the spraying principle is to spray coarsely first and then level, spray point first and then spray back, and adopt a multi-layer spraying method. During the cycle spraying, the bottom layer of concrete is sprayed coarsely with a large displacement, and the outer layer is sprayed finely with a small displacement until the spraying surface is smooth and flat. This method can minimize the rebound amount, make the concrete mixture more closely attached to the rock surface, and form a solid bonding layer.
2. Adjustment of admixtures
In order to make the sprayed concrete achieve the effect of anchoring and compaction in a short time, an accelerator is usually added during the spraying process. The amount of accelerator should be adjusted according to the spraying location and the slump of the concrete. Specifically, when the slump is small, the amount of accelerator should be reduced; when the slump is large, the amount of accelerator should be increased.
It should be noted that too much or too little accelerator will increase the rebound of concrete. If the accelerator is too little, the setting time of concrete is too long, the strength growth is insufficient, and the subsequent sprayed concrete will cause rebound; on the contrary, if the accelerator is too much, such as more than 8-10%, the concrete will quickly solidify into a hard surface, causing more aggregate rebound.
3. Concrete spraying on the rock surface of steel mesh
When spraying concrete on the rock surface with steel mesh, it is necessary to ensure that the steel mesh is firmly fixed to the rock base. If the steel mesh is loose or vibrating, the rebound of concrete will increase, causing material waste and affecting the bonding strength of the sprayed concrete.
4. Concrete spraying on the rock surface of hard and soft rocks
The bonding ability of the hard rock base is not as good as that of soft rock, so when spraying hard rock, the thickness of the bottom layer should be as thin as possible. For large areas of hard rock, first sweep the bottom with sprayed concrete, and then gradually increase the thickness of the sprayed layer. In the weak rock area, the thickness of the spray layer can be appropriately increased during the bottom layer spraying to ensure better bonding effect.
Wet spraying manipulators are widely used in modern engineering. By mastering the correct spraying techniques and methods, the spraying quality of concrete can be significantly improved. Adjusting the amount of admixtures, ensuring the firm fixation of the steel mesh, and adjusting the spraying strategy according to the properties of the rock are all key to ensuring the effect of sprayed concrete. Through these techniques and methods, concrete rebound can be effectively reduced to form a tight and solid bonding layer.