# Presentation: 636313

## Slide 1

## DESIGN AND CONSTRUCTION OF A MODULAR MASSIVE DETECTOR AT THE HOMESTAKE LAB

_**Modular Mass**_** – 100 Kilotons**
_**Modular Shape**_** –Cylinder –50m dia x 50m high**
_**Depth**_** – 4200 mwe (cosmic ray rate = 0.1Hz)**
_**Photocathode coverage**_** – 25%**
_**Initial Detector**_** – 3 modules (300 kilotons) **
_**Construction time**_** - 5 years for 3 modules**
_**Cost**_** - ~ $100 M / module**
_**Ultimate detector**_** – 10 modules (1 Megaton)**

## Slide 3

## DETECTOR MODULE DESIGN CHARACTERISTICS

**Excavation stability studies – O.K.**
**(excavation is very similar to SuperK, ~ 25% larger in each linear dimension)**
**Vertical cylinder with concrete liner and multi-layer water tight plastic liner**
**(SuperKamiokande has a steel tank)**
**Photomultiplier tubes can be inserted and removed **_**without**_** draining water**

##  Presentation

**1)** **Summarize excavation stability studies**
**2) Describe excavation procedure **
**3) Photomultiplier size, spacing & resolution**
**4) Budget and Timetable**
**5) Requirements for coming year**

## SINGLE 100 KILOTON MODULE - HOMESTAKE

- March 2002

- Mark A. Laurenti

**	**

## Electronics Hut

**Electronics Hut**

**PMTs**

**50,000 t Water Tank**
******39.3 m ******** H41.4 m**

**Control Units &**
**Observation Room**

**Mt. Ikenoyama**
**Elevation 1368 m**

**SK**

**1,000 m**

**SL 350 m**
**Access Tunnels**

**SL 350 m**

**SL 365 m**

**SL 307.4 m**

## Feasibility Study of a Large Excavation at the Homestake Mine carried out by

**Doug Tesarik, Jeff Johnson, Karl Zipf**
**Hard Rock Stability Group – Spokane Laboratory of NIOSH (formally Bureau of Mines)**

## Methodology

**Case History**
**FLAC-3d numeric modeling**
**Empirical charts from tunneling**

- <date/time>

**Homestake Panel 3 – VCR Study**

- After Pariseau, Duan and Schmuck

**Notes:**
Two specimens from a grab sample from the Yates Formation were prepared for compression tests and 4 specimens were prepared for Brazilian tensile tests

**Notes:**
Two horizontal strain gauges and two vertical strain gauges were applied to the specimen.

**Notes:**
The specimens were loaded to failure.  The average compressive strength was 28,800 psi - about two times the average compressive strength of the Poorman Formation.  The Modulus of Deformation was 14,500,000 psi – about the same as the Poorman Formation.

**Notes:**
Tensile strength was about 1900 psi – about the same as the Poorman formation

## YATES LABORATORY PROPERTIES

- E = 14,500,000 psi
- Tensile Strength = 1890 psi
- UCS = 28,800 psi!

## MATERIAL PROPERTY REDUCTION 

- <date/time>

- MATERIAL PROPERTY REDUCTION

-  Modulus reduced 25%
- Strengths reduced 50%
- Cohesion = 30 deg.

**Notes:**
Elastic Modulus = 3,425,000 psi (25% of laboratory value)
Unconfined Compressive Strength = 6,135 psi (50% of laboratory value)
Tensile Strength = 955 psi (50 % of laboratory value)
Poisson’s Ratio = 0.22 (laboratory value)
Angle of Internal Friction = 30 deg (conservatively chosen)

**Notes:**
Initial stresses were calculated from a linear formula developed from 4 in situ stress measurements performed in the 1970’s and 1980’s.   Elements were shaped like extruded annuli with each side measuring about 6 ft.  The boundaries were about 7 radii away from the room’s rib.

## EMPIRICAL METHODS

- Barton’s Tunneling Quality Index

**Notes:**
Barton’s Tunneling Quality Index, based on underground observations and laboratory compression tests is 71.  For a 50-m roof span, the recommended support requirements are described by category 12.

## RECOMMENDED ROOF SUPPORT - BARTON

- TENSIONED BOLTS
- 2 – 3-m SPACING

## EMPIRICAL METHODS

- GRIMSTAD AND BARTON

**Notes:**
An updated version of Barton’s chart includes shotcrete.  Support recommendations for the NUSL site are described by category 4. 

## RECOMMENDED ROOF SUPPORT – GRIMSTAD AND BARTON

- “SYSTEMATIC” BOLTING
- 5-mm SHOTCRETE

## CONCLUSIONS

- NO “SHOWSTOPPERS”
- A COMPREHENSIVE ROCK MECHANICS STUDY IS MERITED
- GEOLGICAL INVESTIGATION
- ANISOTROPIC MODELING ?
- IN SITU STRESS MEASUREMENTS

## Year One

** **

- Mark A. Laurenti

- March 2002

**6950**

**7100**

**Year One**

## Year Two

**Year Two**

- Mark A. Laurenti

**6950**

**7100**

- March 2002

## Year Three

**Year Three**

- Mark A. Laurenti

**6950**

**7100**

- March 2002

## Year Four

**Year Four**

- Mark A. Laurenti

**6950**

**7100**

- March 2002

## Excavation Sequence of Super-KAMIOKANDE Cavern

## Excavation Procedure for the Rooftop of the Cavern with Pre-Cablebolt Installation

**Long Cablebolts were Anchored Upwardly before Excavating **
**1st Half Sphere of the Rooftop.**
**2nd Half Sphere was Shaped in the Same Procedure.**

## Super-KAMIOKANDE Dome

**Super-KAMIOKANDE Dome**
**under Excavation**
**(since Dec. 1991 until Aug. 1994)**

## Slide 32

|  | One Module | Three Modules |
| --- | --- | --- |
| Construction (including 30% contingency) | $29.1M | $66.1M |
| Photomultipliers and Electronics | $62.1M | $186.3M |
| Other | $7.9M | $7.9M |
| Contingency (Other + PM) | $17.5M | $48.6M |
| TOTAL | $116.6M | $308.9M |

## Chamber Excavation

|  | One Chamber | Three Chambers |
| --- | --- | --- |
| Labor & benefits | $6.060M | $12.030M |
| Mining Equipment Operation | 1.430M | 4.279M |
| Supplies | 4.961M | 14.685M |
| Precast concrete liner | 3.575M | 10.725M |
| Outside contractor | 0.132M | 0.396M |
| Plastic liner | 0.250M | 0.750M |
| Rock removal | 1.000M | 3.000M |
| Mining Equipment-Purchase | 5.000M | 5.000M |
| Contingency-30% | 6.722M | 15.260M |
| TOTAL | 29.130M | 66.125M |

## Photomultipliers & Electronics

|  | Cost for one PM |
| --- | --- |
| 28 cm dia PM tube | $880 |
| Installation/PM | $165 |
| Electronics/PM | $120 |
| Cable/PM | $77 |
| Total per photomultiplier tube | $1242 |

| One 100 kiloton Detector | $62.1M |
| --- | --- |
| Three 100 kiloton Detectors | 186.3M |

## Other items

| Development Labor | $3.000M |
| --- | --- |
| Water Purification System* (for 10 modules) | 4.500M |
| Calibration equipment | 0.400M |
| TOTAL | $7.900M |

## Slide 36

## Slide 37

## SUMMARY

**1) Initial Detector – Three 100 kiloton modules**
**2) Total cost - $308M.**
**3) Construction time – 5 years**