Shotcrete vs. Gunite

Shotcrete is a wet mix system with minimal additional water requirements. The shotcrete is quality-controlled and pre-mixed to meet engineering and structural requirements. The shotcrete is batched by computer, mixed in a truck, then poured into a pump — allowing a safer and faster application, and less fatigue on the nozzelman.

 

Wet-mix is a cleaner and safer process, among many other advantages:

• Documented by batch tickets and additional material can be acquired quickly
• Shooting does not alter the quality of the mix
• Weather does not impact installation
• Shotcrete bonds with the existing concrete better
• Mix is consistent and standard throughout the bin which minimizes human error
• Shotcrete placement encapsulates reinforcing steel consistently
• Cure time is less, allowing you to use the bin sooner
• Dust free atmosphere — meets new OSHA silica standards
• Minimal concrete waste (5%) or approximately 3 CY per silo
• Rebound easily contained and removed using Eco-Pans
• Designed by the industry for larger volume placements
• Wet mix minimizes overspill (No environmental impact)
• All moving parts on equipment can be locked out (LOTO) and minimal exposed moving parts

Gunite is a Dry Mix that can have variations in consistency with a slower application. While the cure time is longer (engineers recommend 28 days), our biggest concern is safety — dry mix can be dangerous because it exposes moving parts (auger), on pre-dampening system, and flying debris.

 

Here’s what you can expect with a dry mix system:

• Dry mix requires pre-dampening for correct hydration process
• Quality of dry mix can be changed by the addition of water at the nozzle and changes in cement content at the mixelvator which can significantly alter the strength of the mix, and leaves more room for human error
• Weather impacts or halts installation process resulting in delays and change orders
• Gunite bond is compromised by rebound reflecting off wall and wall must be wet to adhere correctly
• Gunite bond around reinforcing bar varies in consistency (air pockets)
• Gunite system produces high volumes of dust and requires substantial ventilation and filtration systems to meet new OSHA silica standards
• Gunite sytem produces massive quantities of rebound material (20%) or approximately 15 CY per silo
• Substantial amounts of waste require multiple handlings, more spillage and close coordination of waste dumpsters or trucks and loaders to facilitate removal
• Designed by the industry for smaller volume placements
• Debris, sand, cement will be present at equipment locations due to overspill which is not preferred where containment and cleanliness is an issue (Environmental)
• Large water source needed to hydrate dry mix materials and significant water overflow and leakage

 

Read more about our shotcrete and gunite services here, or reach us at (855)-752-5047/sales@ccsgrouponline.