Rock Slope Design Guide January 2016 TABLE OF CONTENTS SECTION 100 ROCK SLOPE DESIGN BACKGROUND .................................................... 1-1 101 INTRODUCTION ........................................................................................................... 1-1 102 SCOPE OF GUIDE.......................................................................................................... 1-2 SECTION 200 GEOLOGIC EXPLORATIONS, DATA COLLECTION AND PRESENTATION ........................................................................................................................ 2-1 201 INTRODUCTION ........................................................................................................... 2-1 202 DEFINITION OF GEOLOGICAL TERMS .................................................................... 2-1 202.1 Rock Type .............................................................................................................. 2-1 202.1.1 Claystone....................................................................................................... 2-1 202.1.2 Shale .............................................................................................................. 2-1 202.1.3 Siltstone......................................................................................................... 2-1 202.1.4 Mudstone....................................................................................................... 2-2 202.1.5 Sandstone ...................................................................................................... 2-2 202.1.6 Limestone ...................................................................................................... 2-2 202.1.7 Dolomite ....................................................................................................... 2-2 202.1.8 Coal ............................................................................................................... 2-2 202.1.9 Underclay ...................................................................................................... 2-2 202.2 Rock Properties ...................................................................................................... 2-2 202.2.1 Intact Rock Strength ..................................................................................... 2-3 202.2.2 Rock Weathering .......................................................................................... 2-3 202.3 Rock Discontinuities .............................................................................................. 2-3 202.3.1 Bedding Planes .............................................................................................. 2-4 202.3.2 Joints ............................................................................................................. 2-4 202.3.3 Valley Stress Relief Joints ............................................................................ 2-4 202.3.4 Stress Induced Fractures ............................................................................... 2-4 202.3.5 Faults ............................................................................................................. 2-5 202.3.6 Shears ............................................................................................................ 2-5 203 PLANNING OF AN EXPLORATION PROGRAM ...................................................... 2-5 203.1 New Rock Cut ........................................................................................................ 2-5 203.2 Rehabilitation of Existing Rock Cut ...................................................................... 2-5 204 RECONNAISSANCE...................................................................................................... 2-5 204.1 Geology of Ohio .................................................................................................... 2-6 204.1.1 Southwestern Ohio ......................................................................................... 2-6 204.1.2 Central Ohio ................................................................................................... 2-6 204.1.3 Northesastern Ohio ........................................................................................ 2-6 204.1.4 Northwestern Ohio ......................................................................................... 2-7 204.1.5 Eastern Ohio................................................................................................... 2-7 204.1.6 Southeastern Ohio .......................................................................................... 2-8 204.2 Special Care Formations ........................................................................................ 2-8 204.3 Presence of Mining in the Area ............................................................................. 2-8 204.4 Hydrogeology ........................................................................................................ 2-8 204.5 Landslides .............................................................................................................. 2-9 205 EXPLORATION.............................................................................................................. 2-9 205.1 Introduction ............................................................................................................ 2-9 OHIO DEPARTMENT OF TRANSPORTATION January 2016 Rock Slope Design Guide Page i 205.2 Surface Exploration ............................................................................................... 2-9 205.2.1 Geologic Mapping ......................................................................................... 2-9 205.2.2 Outcrop Mapping ......................................................................................... 2-10 205.2.3 Detailed Line Mapping ................................................................................ 2-10 205.2.4 Stratigraphic Profiles ................................................................................... 2-11 205.2.5 Remote Sensing ........................................................................................... 2-11 205.2.6 Interpretation of Structural Geologic Data .................................................. 2-11 205.2.7 Sample Collection ........................................................................................ 2-12 205.2.8 Surveying .................................................................................................... 2-12 205.2.9 Surface Geophysics ..................................................................................... 2-12 205.3 Subsurface Explorations (Borings) ...................................................................... 2-12 205.4 Other Exploration Tools ...................................................................................... 2-12 205.4.1 Down-hole Televiewer ................................................................................. 2-12 205.4.2 Pressuremeter ............................................................................................... 2-13 205.4.3 Borehole Shear Test ..................................................................................... 2-13 205.4.4 Flat Plate Dilatometer Test (DMT) .............................................................. 2-13 206 LABORATORY TESTING........................................................................................... 2-13 206.1 Strength Tests....................................................................................................... 2-13 206.1.1 Uniaxial Compressive Strength Tests .......................................................... 2-14 206.1.2 Direct Shear Tests on Discontinuities .......................................................... 2-14 206.1.3 Point Load Testing ....................................................................................... 2-14 206.2 Index Tests ........................................................................................................... 2-14 206.2.1 Slake Durability Index ................................................................................. 2-15 206.2.2 Unit Weight .................................................................................................. 2-15 207 ROCK MASS PROPERTIES ........................................................................................ 2-15 207.1 Fracture Frequency .............................................................................................. 2-15 207.2 Block Size ............................................................................................................ 2-15 207.3 Seepage Conditions .............................................................................................. 2-15 207.4 Rock Quality Designation (RQD) ........................................................................ 2-15 208 DISCONTINUITY ENGINEERING PROPERTIES .................................................... 2-16 208.1 Orientation ........................................................................................................... 2-16 208.2 Spacing ................................................................................................................. 2-16 208.3 Persistence............................................................................................................ 2-16 208.4 Roughness, Wall Strength, & Weathering ........................................................... 2-17 208.5 Infilling ...............................................................................................................