Cutting tool holder for a tunnel-boring machine and associated cutting assembly

The invention relates to a cutting tool holder (1) for a tunnel-boring machine, comprising: - a housing (2) comprising two cavities (26) formed in opposite walls (20), and - two clamping assemblies (3), configured to be removably mounted in the housing (2) on either side of the rotary knob (10), and each comprising: *a base (32), and * a central spacer (34), movably mounted on the base (32), * two lateral spacers (36), articulated between the base (32) and the central spacers (34) between a retracted position and a clamping position, in which the lateral spacers (36) swing transversely and penetrate into the cavity (26) facing the housing (2).