Calculation of tube concrete elements with strengthened cores by numerical methodOleksandr Palyvoda, Dmytro Yermolenko, Oksana Demchenko, Oleksandr Andriichuk and Oleksandr NyzhnykE3S Web Conf., 166 (2020) 08002DOI: https://doi.org/10.1051/e3sconf/202016608002