
Shotcrete for wet process applications - Lower permeability
BATIMIX Concrete 582 is a pre-blended shotcrete mixture used in wet process applications where lower permeability features are sought. It is made from a blend Portland cement, a combination of selected additives, and carefully-graded fine and coarse aggregates. It exhibits enhanced shotcrete characteristics and physical properties.
BATIMIX Concrete 582 is thoroughly mixed with water and introduced into the shotcrete equipment. The wet material, which exhibits improved cohesion characteristics, is pumped through the hose and compressed air added at the nozzle. It impacts the surface at high velocity resulting in a well-compacted product that is easy to place and consolidate.
BATIMIX Concrete 582 products are used to strengthen and repair existing structures. They are also used to build complex architectural shapes for skateboard parks, swimming pools, and earth retaining structures. The surfaces can have horizontal, vertical, or overhead orientations. They are also used to line and rehabilitate the cementitious substrates of sewers, tunnels, reservoirs, and water main.
BATIMIX Concrete 582 has the following characteristics:
BATIMIX Concrete 582 contains cement and silica fume. It is irritating for the eyes and skin. In case of contact, rinse immediately with plenty of water. Wear suitable gloves. For further information, kindly refer to the product Material Safety Data Sheet.
BATIMIX Concrete 582 meets the requirements of ASTM C 1480 for Packaged, Pre-Blended, Dry, Combined Materials for Use in Wet or Dry Shotcrete Application Type CA, Grade LP (lower permeability).
1 – Substrate preparation 1.1 – Support and nailing works: All surfaces to be in contact with BATIMIX Concrete 582 must be free from dust, oil, grease, or any other foreign substance that may interfere with the bond of the material. Remove all loose or delaminated sand and rock. Moisturize the area with clean water, leaving the substrate saturated but free of standing water (SSD condition).
1.2 – Repair and rehabilitation works: Concrete must be structurally sound and fully cured. Saw cut the edges of the repair location to a depth of at least 15 mm. Remove all spalled, severely cracked, deteriorated, and loose concrete from existing substrate by chipping, water blasting, or other mechanical methods. Care should be taken to remove all oxidation and scale from the exposed reinforcing steel. Adequate pre-wetting with no glistering water should be achieved prior to shotcreting.
2 – Product preparation A 50-kg bag of BATIMIX Concrete 582 should be mixed with 3.5 to 4.5 liters of clean water, depending on the desired slump consistency. The mixing should be done with a medium-speed mechanical mixer for a minimum of 3 minutes until obtaining a consistent homogenous material.
3 – Application Place the wet BATIMIX Concrete 582 into the hopper of the delivery machine, such as a concrete pump, and shot directly onto the substrate. The nozzle operator should give enough attention to the angle of application, i.e. 90° and distance from the substrate, normally 0.8 to 1.8 m. Refer to ACI 506 “Guide to Shotcrete”.
The surface can be trowelled smooth while BATIMIX Concrete 582 is still wet. Typical application depths can be up to 150 mm. In case greater thicknesses are required, it is recommended that subsequent layers be applied after 24 hours from the first application.
4 – Curing Good curing conditions are extremely important to optimize the physical properties of BATIMIX Concrete 582. Curing should start soon after the material has reached its initial set according to ACI 308 “Practice for Curing Concrete”. Continuously moist cure for a minimum of 7 days. Alternatively, moist cure for a minimum of 24 hours and then apply a curing compound which complies with ASTM C 309. This is particularly critical in high ambient temperatures, high winds, and low humidity.
| ASTM Test Method | BATIMIX Concrete 582 Results | | --------------------------------------------- | ---------------------------- | | Water per 50-kg bag, liters | 3.5 – 4.5 | | Initial slump (C143), mm | 100 | | Fresh wet density (C138), kg/m³ | 2,350 | | Air content (C231), % | 2 | | Average setting time (C403), hours | 1 – 2 | | Compressive strength after 28 days (C39), MPa | min. 37 | | Flexural strength after 28 days (C78), MPa | min. 7.5 | | Adhesion to substrate (D4541), MPa | > 3 |
The following data are averages of several tests under laboratory conditions of 23 °C and 50% R.H.; they may be significantly affected by the shotcrete dry application process in the field.
BATIMIX Concrete 582 should be stored in a closed and dry place. Avoid freezing and excessive temperatures. Unopened bags have a shelf life of six months when stored as recommended.