1. Meeting No. 3 : Scope - Studies for HL-LHC Civil Engineering
Celine Bellenger
Yung Loo
Claire Wilson
Matt Sykes
Dr David Hiller
19/03/2015

2. Scope of work Proposal 1 Task 1: Roadheader Vibration Support
Task 2: LHC displacement predictions from Hi-Lumi tunnelling
Output: Summary technical note
Proposal 2
Task: Baseline toolbox of typical construction activity and low excavation vibration methods
+ Meeting at CERN to present main findings

3. Out of scope – Vibration testing support
No realistic alternative to improve current prediction/approximation without conducting some site trials and measuring with specialist instruments that give the full range of vibration that is of interest
Test measurements necessary and mandatory to understand and investigation of the profile of vibrations across the affected length of the LHC
Vibration testing support has been removed from the offers (no site trials)
Some readjustment/recalibration will be needed in all cases: to be planned

4. Scope of work – Task 2: LHC displacement
Task 2: LHC displacement predictions from Hi-Lumi tunnelling
Analysis to calculate the instantaneous ground movements on the LHC from the HL-LHC tunnelling works, at Point 5.
Ascertain relevant geotechnical data (case studies, sensitivity analysis)
 Results in 3 directions (3D ground movement modelling) to determine potential tunnel induced ground movements and associated sensitivity analyses.
Nota 1: need to know understand tolerable limits along the LHC
Nota 2: potential long term movements not considered

5. Scope of work – Task 2: LHC displacement

6. Scope of work – Task 2: LHC displacement
12m outer diameter shaft
Proposed High Luminosity LHC tunnel
Existing LHC tunnel modelled as displacement lines

7. Scope of work – Task 1: Roadheader data
Task 1: Roadheader Vibration Support
Investigate roadheader suppliers
Case studies
Potential vibrations and impacts on the LHC from the HL-LHC tunnelling works
Nota: need to know understand tolerable limits along the LHC.
PPV = 2* π * f *A
With PPV = Zero-to-Peak, or Peak Particle Velocity (Units: m/sec, mm/sec)
f = Frequency (Units: Hertz)
A = Zero-to-Peak, or Peak Displacement (Units: m, mm)
i.e. for 1 μm:
Frequency
Amplitude
PPV Hz μm
mm/s 50
0.6
0.19 1
0.31
100
0.63
150
0.94
200
1.26

8. Scope of work – Task 1: Roadheader data
Suppliers contacted for roadheader vibration data:
Sandvik:
Some information available on vibration (see following slide)
Lowest values in the 0.01mm/s range at 40m distance, or just below
Herrenknecht:
Do not manufacture roadheader (only roadheader booms for some open face tunnelling machines)
No published information on vibration available, even for TBM
Eickhoff Bochum :
Do not manufacture roadheader anymore (second handed roadheader on the market)
No vibration data

9. Scope of work – Task 1: Roadheader data
Further information from Sandvik:
Vibration measurements only from heavy duty roadheader series MT720
Ground conditions, physical properties of the material and influencing parameters like acoustic impedence, reflection etc make it difficult to compare roadheader applications
Roadheader max frequency 80Hz, mean 40-70Hz – in agreement with Dr Hiller
“Vibration intensities at a Roadheader application are pretty low compared to a D&B operation and even approx m behind the operating face we were not able to differ between Roadheader induced vibrations and background noise!”
More detailed project information on 4no. projects – geophones within the tunnel behind the face and in boreholes adjacent to tunnel

10. Scope of work – Task 1: Roadheader data
Suppliers contacted for roadheader vibration data:
Erkat:
Work only with drum cutters
According to their experience on several jobsites the vibration level will be below 0,03 mm/s.
Project Sonnenburg in North-Italy
Rock : Quarz Phylites (UCS MPa)
Drill and Blast
0.03
Roadheader

11. Scope of work – Task 1: Roadheader data
Suppliers contacted for roadheader vibration data:
CSM-Bessac:
Do not manufacture roadheader (open face with drum cutter)
Experience on molasses: Saint Genis Pouilly France-Switzerland + Toulouse metro
No information available on vibration
Alpine:
No answer at the moment
MSB-IBS (Schmitt Gruppe):

12. Scope of work – Task 3: Alternative construction methods
Task 3: Construction baseline toolbox
Establish a vibration baseline including roadheader, hydraulic breaker, percussive drilling, coring
Investigate low vibration excavation method/impact including expanding demolition agent, hydraulic fracturing
Nota: limits will be the data we can collect.

13. Scope of work – Task 3: Alternative construction methods
PPV in in/sec at 100 ft (30 m)
1 inch=25.4 mm
Preliminary findings
Compared to mm/s for roadheader
0.08 mm/s
0.15 mm/s
0.08 mm/s
19 mm/s
Source: Report for West Connection Bridge project, Washington state
0.28 mm/s

14. Scope of work – Task 3: Alternative construction methods
Expanding demolition agent - 2 Suppliers contacted:
Ecobust
Used in Xstrata Mines in a narrow tunnel
Waiting for more information
Dexpan
Used with mine, but confidential information
No Vibration, except for the drilling part
Different product depending on ground temperature
Up to 170 MPa rock strength
Limitations: size and depth of the holes (1.5’’ to 2’’ diameter = 3.8 cm to 5cm and 5’’=13 cm depth)
Arup has done research for a Sensitive structural project (Australia)
Key is to provide as much free space for the rock to crack into by using burn holes

15. Any Questions? Next step : Consolidate what we have on vibration
Analyse 3D displacements
Any Questions?

16. Backup Slides

17. Re-cap: Post-Meeting no.1
Mechanical Excavation
30-80Hz Region dominates
Tails off to 200Hz
45m away, PPV ~ 2x10-4 m/s, 50Hz
= zero-to-peak displacement of
6x10^-7m (0.6μm)
[comparable to 1μm limit?]
2-3% of the max at 200Hz

18. Re-cap: Post-Meeting no.2
Sandvik data as a comparison – lowest values they have presented are in the 0.01mm/s range at 40m distance, or just below – therefore they are capable of reaching the same order of magnitude of vibration as suggested and achieved in the presented past projects.
But is this within tolerable physics machine limits?
Possibilities for mitigation are small to none
“Mitigation options for mechanized tunnelling activities are limited. In some circumstances, it might be possible to limit working hours” - British Standard
Possibility to engage with Sandvik with further detailed geotech parameters and vibration criteria to understand in more detail possibilities and limitations
Identified conventional vibration limits of existing roadheader machines. Need to understand if these are tolerable, and physics requirements can be compatible at these limits.

19. Case Study - Roadheader Vibrations
Project
Location
Geology
Lowest predicted ground borne noise vibration criteria PPV (where possible at a distance ~40m)
Range of ground borne noise vibration recorded PPV
Comments
Any project guidance on sensitive structures/equipment
Brisbane Airport Link,
Brisbane, Australia
Rock (limited info)
0.01mm/s at 40m distance
n/a
Focus on damage/human comfort in buildings
Typical satisfactory vibration levels for sensitive buildings – Maximum 0.5mm/s
Brisbane Airport Link, changed project,
0.01mm/s
BaT project 3
0.08mm/s at ~35m distance
Sensitive structures identified
Linking Melbourne East-West Link 4
Melbourne, Australia
Basalt and siltstone
0.15mm/s at 40m distance
Sensitive structural project 5
Australia
Weak rock (sandstone)
0.2 mm/s
mm/s (0.05mm/s measured at ~30m distance)
Safely within vibration criteria for “sensitive structure”
Road header successfully used in close proximity to sensitive structural elements
Northern Link 6
Threshold was assessed as that of human perception ~0.15mm/s
mm/s (no distance information)
Table summarising the vibration levels for different projects, specifically using a road header

20. Sandvik MT720 – Montreal, Canada (135Tonne)
Data from Sandvik
Shale and limestone

21. Sandvik ATM105 – Pozzano, Italy (135Tonne)
Data from Sandvik
No geology information

22. Vibration data classified according to geology