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CERN acquires four new buildings for the High-Luminosity LHC

Four buildings set to house technical infrastructure for the future accelerator were delivered to CERN by contractors between June and September


SC3 buildings for the HL-LHC Project
The SF and SHM buildings are located at Hi-Lumi Point 1, close to the ATLAS experiment and the Meyrin site (Image: CERN)

Bad news for those of us who already struggle to find our way around the maze of CERN’s buildings: four new structures have popped up this summer. The JVMM (Joint Venture Marti Meyrin) and CIB (Consortium Implénia Baresel) consortia have handed CERN the keys of four new surface buildings intended to house infrastructure that will serve the new High-Luminosity LHC (HL-LHC) galleries at Points 1 and 5, marking the end of “SC3” (Sectional Completion 3).

The “SF” and “SHM” buildings at Point 5, which were delivered at the end of June, are identical in every way to – and fulfil the same purpose as – the buildings bearing the same names at Point 1, which were delivered at the beginning of September. Currently all empty, the four concrete giants will receive delivery of their first equipment (travelling cranes, doors, electricity, lighting and ventilation, etc.) in the coming weeks, and the HL-LHC infrastructure will come in a second stage.

The two SF buildings will mainly house cooling towers and primary water circulation pumps for cooling surface and underground equipment. The SHM buildings will house the cycle compressors for the cryogenic cooling systems. These machines compress helium from 1 bar to just over 20 bars (successive expansions of this compressed helium in the cold box then produce the cold needed to cool the underground systems).

Even though they are empty, the new buildings already have certain unique characteristics. The floors of the two SHM are entirely coated with waterproof resin, preventing any environmental contamination by potential leaks of the compressor lubricant oil. In addition, the walls are soundproofed to protect our ears from the compressors’ droning, which can reach 105 decibels.

The four buildings, two on each of the CERN sites, are located at either end of their future respective gallery chains, via which they will be connected to the SU, SD and SE service buildings, themselves connected to underground galleries. The galleries will be delivered as part of “SC5”, scheduled for the end of 2022, which will bring the HL-LHC project’s major civil engineering work to a close.

With SC3 out of the way, that’s the next focus for many of the teams involved in these mammoth undertakings (the SCE-PPM group’s civil engineering team, contractors and design offices). While the scale of the SC3 buildings may seem small compared to that of the vast underground galleries, building them on schedule is nevertheless a crucial milestone in the HL-LHC project.