Batimix Concrete 561

Description

BATIMIX Concrete 561 is a pre-blended shotcrete mixture used in dry-process applications. It exhibits sulfate resistance features. It contains Portland cement type V, selected additives, and carefully-graded fine and coarse aggregates.

The dry material is introduced in the shotcrete machine, 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.

Main Purpose

BATIMIX Concrete 561 are structural materials used to repair and rehabilitate horizontal, vertical, and overhead surfaces of bridges, garages, beams, and slabs. It is also used for ground support in mining and tunneling applications, the lining of sewers and shafts, slope stabilization, and soil nailing. Substrates on which the product may be applied include rock, soil, brick, or any other cementitious-based surface.

Features

BATIMIX Concrete 561 has the following characteristics:

• Easy to use, suitable for both interior and exterior shotcrete works
• High early and final compressive strength without added chlorides
• Reduced bleeding and sagging
• High degree of adhesion and bonding to the projected substrate
• Improved resistance to sulfate attacks

Properties

• Appearance / color: powder/grey
• Bulk density: around 1.81
• Chloride content: nil
• Grain size: 0 to 10 mm (upon request, this product can be made to smaller maximum aggregate sizes)
• Yield : approx. 0.023 m³ per bag of 50 kg

Health and Safety

BATIMIX Concrete 561 contains cement. 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 Material Safety Data Sheet.

Directions for Use

1 – Substrate preparation 1.1 – Support and nailing works: All surfaces to be in contact with BATIMIX Concrete 561 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 – Application Place BATIMIX Concrete 561 directly into the hopper of the delivery machine. It may be introduced dry as well as pre-dampened at a maximum of 2 liters per 50 kg bag.

Once the placement has started, the nozzle operator is responsible for adding the correct amount of water at the nozzle to achieve proper hydration of the sprayed material. This water / cement ratio is critical and directly affects the physical properties and performance of the hardened product. Refer to ACI 506 “Guide to Shotcrete”. The surface can be trowelled smooth while BATIMIX Concrete 561 is still wet.

3 – Curing Good curing conditions are extremely important to optimize the physical properties of BATIMIX Concrete 561. 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.

Specifications / Compliance with Standards

BATIMIX Concrete 561 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 SR (sulfate resistant).

Physical Properties

| ASTM Test Method | BATIMIX Concrete 561 Results | | --------------------------------------------- | ---------------------------- | | Water per 50-kg bag, liters | 3.5 - 4 | | 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. 35 MPa | | Flexural strength after 7 days (C78), MPa | min. 7.5 MPa | | Adhesion to substrate (D4541), MPa | > 2.5 |

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.

Storage

BATIMIX Concrete 561 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.

Packages

• 1 t big bag
• 50 kg paper bag