The aim of this paper is to model numerically concrete flow inside formworks like the Lbox. For this purpose, we use a finite element method with Lagrangian integration points (FEMLIP). We are able to follow in time and space material motion with any type of material behaviour, including non-linear and time-dependent ones. We also can deal with free surfaces or material interfaces. Bingham's rheology is used for fresh concrete behaviour. In order to compare with experiments, we have considered three concretes (OC, HPC and SCC) with contrasted rheologies. Their yield stress is identified by experimental slump tests and also compared with the value given by a formulation concrete software. Experimental data are found to be quite close to numerical predictions. We have also made some experimental flow tests in a LBOX. We measured the flow speed and the flow shape in the final stage. The numerical modelling of these experiments is very encouraging and shows the capability of the FEMLIP using the Bingham's law to model concrete flow and filling properties