In tunnels, mines and various underground projects, wet concrete spraying technology has become one of the important means of support work due to its high efficiency and speed. However, how to improve construction quality and reduce material waste by accurately adjusting the spraying parameters is the direction that industry technicians continue to explore. This article focuses on two key factors in the wet concrete spraying process-spraying angle and spraying distance, and explores their impact on construction results.
Choice of spraying angle
In wet concrete spraying operations, the setting of the spraying angle directly affects the adhesion of concrete to the target surface. For vertical or nearly vertical working surfaces, the ideal spraying angle should be kept vertical (90°), which ensures that the concrete is evenly distributed and minimizes rebound. However, when dealing with non-vertical structures such as side walls, fine-tuning strategies are required. At this time, it is recommended to adjust the nozzle angle to about 10° slightly below the horizontal line, that is, about 80°. This technique helps the concrete to better adhere to the thicker layer and prevent the problem of sliding due to gravity.
When facing complex walls with grid or steel reinforcement, it is particularly necessary to tilt the nozzle at a moderate angle (usually not less than 70°). This can not only effectively avoid obstacles, but also ensure that the concrete fully fills the gap and enhances the overall stability of the structure. It is worth noting that excessive tilting will cause the material to roll on the surface, forming an uneven "wavy" surface, thereby increasing the rebound rate and affecting the construction quality.
Precisely control the spraying distance
In addition to the spraying angle, the spraying distance is also a key variable that determines the success or failure of the construction. A reasonable spraying distance can significantly reduce the rebound of the material and promote the rapid solidification of the concrete. In practice, the optimal distance range is often between 0.6 meters and 1.2 meters. Operations within this range can ensure the concentration of the concrete beam and achieve the lowest rebound loss. In addition, in order to further optimize the spraying effect, the air pressure at the nozzle must be maintained within the range of 0.3 to 0.5 MPa to achieve an ideal pressure balance point, neither over-compression nor lack of power, to ensure that the concrete can smoothly fit the wall and form a solid protective layer.
By accurately controlling the spraying angle and spraying distance in the concrete wet spraying process, we can not only greatly improve the quality of the project, but also effectively save costs and shorten the construction period. In the future, with the continuous advancement of technology, I believe we can carry out refined management in more details and promote the sustainable development of the entire industry.