spraycrete

The Australian standard for concrete is AS 3600. This standard covers the production, sampling, testing and classification of concrete. It also includes requirements for the design and construction of concrete structures.

The minimum thickness for concrete will vary depending on the application. In general, however, a minimum thickness of 4 inches is recommended.

If you use too much cement in concrete, it can adversely affect the strength and durability of the final product. The amount of cement in a concrete mix is typically expressed as a "cement to sand ratio" or a "cement to aggregates ratio". A higher-than-normal cement ratio means that there will be more cement paste surrounding the individual aggregate particles, which can make the concrete weaker and more susceptible to cracking. Conversely, using too little cement will also lead to substandard concrete; in this case, the mixture will be more likely to experience shrinkage cracking as it dries. It's therefore important to get your proportions right when making concrete, in order to ensure a high-quality final product.