Shotcrete Dry Spray/Gunite
RIX specialises in shotcrete dry spraying, also known as ‘Dryshot’ in Australia. Dry spraying differs from wet shotcreting as compressed air blows a dry mix through a hose. The dry spray has water added at the nozzle, just prior to discharge.
Dry Spraying is perfect for the following situations:
- Coal mines
- Concrete repair
- Small quantities
- Long pumping distances
- Limited access or remote areas
The dry spray nozzleman’s training is paramount as they control the quality of the dry spray and the addition of water at the nozzle. Mixing of the dry spray at this point is crucial to the final mix strength and quality.
Centre: RIX dry spray nozzleman spraying overhead for ground support in a new tunnel portal.
Left and right: Dry spray mix trial in operation. The test being performed in RIX’s test facility is the Round Determinate Panel Test (RDPT). These panels are 75mm thick and 800mm in diameter and are tested in accordance with ASTM C-1550, with 3 pivots symmetrically arranged around the circumference and loaded at the centre. Energy absorbed and load resistance exerted at a specified deflection represents the ability of the specimen to redistribute stress following cracking. By this method, the dry spray mix’s application and post-crack capacity (or toughness) can be quantified for quality assessment.