(19)

(11)

EP 4 232 635 A1

(12)

(43) Date of publication: 30.08.2023 Bulletin 2023/35 (21) Application number: 21823806.1 (22) Date of filing: 29.11.2021

(51) International Patent Classification (IPC):  E02D 3/12(2006.01) E21D 20/02(2006.01) E21D 9/00(2006.01) (52) Cooperative Patent Classification (CPC): E02D 3/12; E02D 31/10 (86) International application number: PCT/EP2021/083433 (87) International publication number: WO 2022/112580 (02.06.2022 Gazette 2022/22)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 27.11.2020 EP 20210302 (71) Applicant: Construction Research & Technology GmbH 83308 Trostberg (DE)	(72) Inventors: GRASSI, Davide 31100 Treviso (IT) SPAGNOLI, Giovanni 83308 Trostberg (DE) (74) Representative: Lorenz, Klaus Uwe  Master Builders Solutions Deutschland GmbH EB/IP Dr.-Albert-Frank-Straße 32 83308 Trostberg 83308 Trostberg (DE)