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GE 5471 ROCK ENGINEERING CH 2 – Character of Rock Materials

Dr. Norbert H. Maerz

Missouri University of Science and Technology

(573) 341-6714

norbert@mst.edu

Instructional Objectives

1. Explain the role of testing intact rock materials.2. List the genetic rock types and subtypes, and predict their properties

as engineering materials.3. Classify rock types, using field tables.4. Explain the effect of mineralogy on the engineering properties of the

rock.5. Define strength, hardness, abrasiveness, durability, and swelling

potential, and predict the effect on engineering properties.6. Calculate bulk density, specific gravity, unit weight, and porosity of

rock.7. Propose rock tests that would better predict the engineering behavior

of rock masses.8. Solve using calculations, problems involving the following

properties of rock: Bulk density, specific gravity, unit weight, and porosity.

Role of Testing

1. Index Tests

2. Design Tests

3. Quality Control Tests

4. Research Test

Genetic Rock Types (what’s in a name)

• Igneous

• Metamorphic

• Sedimentary

Genetic Structures

• Jointing

• Faulting

• Folding

• Schistosity,

• Gneissosity

• Bedding

• etc.

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Rock Classification

Pictures from the collection of Dr. J. A. Franklin. Pictures from the collection of Dr. J. A. Franklin.

Concept of Families

• Rocks of similar features may have similar engineering properties

• GMU’s

Igneous Rock

Pictures from the collection of Dr. J. A. Franklin.

Metamorphic Rock

Pictures from the collection of Dr. J. A. Franklin.

Sedimentary Rock

Pictures from the collection of Dr. J. A. Franklin.

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Mineralogical Approach

• Quarto-felspathic (Quartz and feldspar)

• Lithic Basic

• Micaceous

• Carbonate

• Saline

• Pelitic

Clay Minerals (phylosilicates)

• SMECTITE (MONTMORILLONITE)

• ILLITE

• KAOLINITE (REFRACTORY CLAY)

• VERMICULITE

Engineering Characteristics of Rocks (REV)

Physical Characteristics

• Field Identification

Strength

Hong Kong Geotechnical Control Office

Color / Texture

Hong Kong Geotechnical Control Office

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Weathering / Alteration

Hong Kong Geotechnical Control Office

Rock Name / Structure

Hong Kong Geotechnical Control Office

Discontinuities

Hong Kong Geotechnical Control Office

Weathering

Hong Kong Geotechnical Control Office

PorosityMechanical Characteristics

• Strength

• Hardness

• Abrasiveness

• Slake durability

• Swelling Potential

• Other tests (see book)

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Index Tests

Pictures from the collection of Dr. J. A. Franklin.

Strength

Picture from the collection of Dr. J. A. Franklin. Diagram from www.es.ucsc.edu/~tulaczyk/EART142_2003/ RockMechanics.pdf

Hardness

http://www.hochbaulager.ch/usa/produkte/gruppe1/betonpruefhammer.html

Abrasiveness

Slaking Durability

www.hmc-hsi.com/pdf1/175.pdf (Humbolt)

Swelling Potential

http://www.ldg-gss.com/lab7.html

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SLIDE SHOW

(enjoy)

Visual Examination

From the collection of J. A. Franklin, F6, F7

Sandstone Thin

Section

From the collection of J. A. Franklin, SSS 8, 7

Sandstone & Dolomite

thin section

From the collection of J. A. Franklin, PP5, 4

Diabase & Gabbro thin section

From the collection of J. A. Franklin, PP8, SSS1

Schist & Gneiss thin section

From the collection of J. A. Franklin, SSS9, 11

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Point LoadTest

From the collection of J. A. Franklin, K19

Point Load Testing

From the collection of J. A. Franklin, 2Y 18-20

SchmidtHammer

From the collection of J. A. Franklin, K11, 12

HardnessTesters

From the collection of J. A. Franklin, K13, 15

Slake Durability

Test

From the collection of J. A. Franklin, AA1, F9

Shale Rating System

AA1, F9AA1, F9

From the collection of J. A. Franklin, E2