Real crack predictions for reinforced concrete (RC), and especially hybrid reinforced concrete (SFRC), are hard to make for real life engineering projects. In the case of plates (slabs and walls), the strain over a region length is often constant and crack localisation on element level cannot be found. In the new DIANA 10 release it is possible to automatically adapt the material properties on integration point level via a real variation contribution over the model using random fields. Based on the material covariance the material strength parameters are randomly distributed over the integration points with taking into account a correlation influence length. This paper describes the background of implementation of random fields. And, in particular shows the difference in crack predictions when using random fields in FEA models in comparison to the constant smeared crack approach. And proves that the results, having utilised the random fields, show a better localisation of cracks. Finally a real live slab case is analysed via different material approaches.