No-fines concrete is obtained by eliminating the fine material sand, from the normal concrete mix. The single-sized coarse aggregates are surrounded and held together by a thin layer of cement paste giving strength of concrete.
- Mix Proportions
Generally, the cement: aggregate ratio by volume is in the range from 1:6 to 1:8. Leaner mixes (1:8 to 1:10) reduce the likelihood of the pores being blocked by cement paste. Thus for drainage layers where lower strength can be tolerated, 1:10 is preferred. The water-cement ratio needs to be kept low, eg 0.4–0.45, to ensure the cement paste coats the aggregates and does not runoff.
- Compressive strength:
This is lower than conventional concrete and is a function of the aggregate: cement ratio, the water-cement ratio, and the degree of compaction (the density). Available strengths are from 7 to 15 MPa. A mix with an aggregate: cement ratio of 8:1; a water-cement ratio of 0.4; and a density of 1850 kg/m3 has a strength of approximately 7.5 MPa.
- Drying Shrinkage:
Much lower than conventional concrete, eg in range 0.0002–0.0003 microstrain.
High - Water and air flow easily through it, but no quantitative data is available. Blocking of the pores is more likely to occur the smaller the aggregate size.
Polypropylene Fibers are added to Plaster Mixes to prevent plastic shrinkage cracking in harsh weather conditions. It is still advisable to cure plaster by wetting and covering in harsh ambient weather conditions.
- ◘ Car Parks - (10 - 15 Mpa)
Provides free-draining pavements for light traffic
- ◘ Drive-In - (25 - 30 Mpa)
Free-draining and directed water flow
- ◘ Walk Ways - (7 - 15Mpa)
Water is directed to underground soil preventing water run off or build up on pdestrian path ways.
- ◘ Drainage Layers - (7 - 15Mpa)
Used as drainage layers on civil engineering projects.
Concrete is discharged straight from the vehicle's chute to the placement area. Where the 4m chute extension can't reach the placement area, wheelbarrows, skip, crane lift or conveyor belts can be used.
To order concrete you will need the following information:
1. Strength required
2. Volume(m³) Required
3. Delivery Address
We will send a quote based on the supplied details. If you are not sure about the volumes required, contact your engineur or architect for this information. You can also view the Volume calculator page. Please remember that it is always wise to measure on site as well and not just calculating based on plan drawings. Excavations, trench depths and surface level can influence the actual volumes required.