Skilled Worker for Underground Construction

As part of the development of our Sigma Temporaire - Special Works (building & civil engineering) department, we are supporting a leading Swiss company specialized in the realization of complex underground structures: road and rail tunnels, technical galleries, buried structures, and major infrastructure. Intervening on strategic projects with high technical requirements, this company stands out for its expertise in mechanized excavation, support, and final lining of underground structures. To strengthen its teams, we are looking for a Skilled Worker for underground construction / Tunnel (M/F), an experienced professional, able to evolve with autonomy in a demanding, structured, and rhythmic environment. Your missions: You will intervene on underground construction sites, in the excavation, support, and/or lining phase. Depending on your specialization and the progress of the site, you will be called upon to: Excavation & support Participate in traditional or mechanized tunnel advancement operations Carry out bolting, nailing, installation of metal grids and arches Implement shotcrete (gunitage / shotcrete) for primary support Carry out injection and consolidation work on the ground Tunnelier Intervene in the backup area of the tunnel boring machine Participate in the assembly of prefabricated rings (voussoirs) Ensure logistics, light maintenance, and security work around the machine Contribute to the smooth running of the tunnel production cycle Lining & major underground work Carry out vault, slab, and wall formwork Installation of scaffolding, sliding formwork, or tunnel formwork Participation in the casting of final lining concrete Finishing work in an underground environment Organization & safety Reading of plans and respect for technical instructions Work in posted teams (2x8 / 3x8 / night / weekend) Strict respect for SUVA safety standards and site procedures Active participation in collective safety in a confined environment Your profile Significant experience in underground construction, tunnels, or galleries Good mastery of at least one of the following areas: support (shotcrete, bolting) work on tunnel boring machines concrete formwork in underground environments Habit of working in a confined and rhythmic environment Ability to work irregular hours and in posted teams Sense of responsibility and strict respect for safety rules Appreciated skills in reading plans Team spirit, reliability, and commitment What we offer An active collaboration with a dynamic team, with a sharp technical expertise, particularly in special works in alpine and difficult-to-access environments Absolute discretion guaranteed, with an immediate or agreed-upon start date Attractive remuneration, linked to the position and your skills Personalized support throughout your mission, with a dedicated Sigma Temporaire contact Access to a network of diverse companies, offering opportunities in technical and strategic sectors Flexibility of missions, to reconcile professional and personal life Prospects for evolution, with opportunities for permanent positions with our partner clients Simplified recruitment process, for rapid and efficient integration Is this position of interest to you? Send us your application without further delay, we look forward to receiving your candidacy.