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This test simluates the flow of concrete into rectangular formwork. The concrete is initially kept in rectangular reservoir and released by the lifting of vertical gate, due to gravity forces. This simulation has been performed in 3D to illustrate the capability of simulation code to solve 3D problems. The geometry of the tests is shown in Fig. 1. The dimension of the rectangular formwork are 0.7 x 0.2 x 0.15 [m], dimensions of box with concrete 0.27 x 0.2 x 0.12 [m]. Concrete flows only due to gravity. Main focus is to assess the influence of boundary conditions and effect of varying yield stress.

Fig.1: The geometry of the LCPC test	Fig.2: Computational mesh

The somputational model consists in total of 10052 nodes and 50880 tetrahedral elements with linear approximation of velocity and pressure fields. In total, 20 time steps were used in simulation. Concrete is modeled as a Bingham fluid with different set of material parameters. On all vertical walls and on the bottom of the box, “slip with friction” boundary conditions are prescribed (normal component of velocity is set to zero and tangential component is proportional to stress vector). The top of the box is assumed to be opened and zero pressure boundary is assumed.

Example of OOFEM input for LCPC Box simulation can be downloaded from here: channel_beta20_tau40_mu40_oofem.in

In the videos below, the comparison of the flow with different value of friction and yield stress is shown. In the first video, concrete has yield stress equal to 40 [Pa] and plastic viscosity 40 [Pa.s], while friction parameter is equal to 10.0 and 80.0. In the second video, friction parameter is in both cases equal to 20.0 and plastic viscosity to 40 [Pa.s], while yield stress is 40 [Pa] and 400 [Pa].

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