The paper describes the vibropresing process using for building concrete samples and the effect of vibropressing process [1] on the strength of concrete. The material testing machine Zwick was used for experiments with raw concrete vibropressing. The form of samples is cylindrical with diameter 84.5 mm. The vibropressing regime is described by formula f=f0+fAsin(ωt) was realizing changing three parameters - f0 pressing force (10-50kN), fA force amplitude (1-11kN) and frequency(10-50 Hz). The experiments were conducted according to the Mean Square Error Latin hypercube design [2]. The influence of pressing force, force amplitude and frequency on the vibropressing process [3] and on the strength of samples was investigated. The registered force curves were smoothed and approximated with 3 parameter functions. The results of crash test are analyzing using software Design Expert and EDAOpt. The dependency model of the strength of samples on the three parameters was identified and used process optimization.