Analytical calculation of tube confined concrete elements with strengthened coresOleksandr Palyvoda, Dmytro Yermolenko, Oleksandr Andriichuk, Mindaugas Vaicekauskas and Intars DicmanisE3S Web Conf., 280 (2021) 03005DOI: https://doi.org/10.1051/e3sconf/202128003005