Tunnel formwork ndi mtundu wa ophatikizana mtundu formwork, amene amaphatikiza formwork wa kuponyedwa-mu-malo khoma ndi formwork wa kuponyedwa mu malo pansi pa maziko a yomanga formwork lalikulu, kuti athandize formwork kamodzi, tayi. chitsulo chachitsulo kamodzi, ndi kutsanulira khoma ndi formwork mu mawonekedwe kamodzi pa nthawi yomweyo. Chifukwa cha mawonekedwe owonjezera a mawonekedwewa ali ngati ngalande yamakona anayi, amatchedwa tunnel formwork.