Analysis of rock mass strength.Only Part B, sample example is provided.Allocated tunnel: Homer TunnelAllocated confing stress: 0.4
Assign 1 GEOLOGY Instruction and Rubric Melbourne and Rock Mass GEOM2131 Geology: Assignment 1 Part A: Melbourne Interpretive Geological Cross-section Submit one page in the format of the powerpoint template file provided. Any graphical and numerical working must be shown on the submitted pages. Part B: Tunnel portal photo and field data analysis for rock mass strength Submit two pages in the format of the powerpoint template file provided. Any graphical and numerical working must be shown on the submitted pages. Part A & B are to be submitted as a single pdf file. Do not add any cover sheets or additional pages to your three page submission. Do not submit any additional files. Part A: Melbourne Interpretive Geological Cross-section Complete a geological cross-section for the three drill holes allocated to you from the Melbourne database. Use a vertical exaggeration of 10. Present the cross-section on a single page in landscape orientation. The content and layout of the section and associated data required is outlined in presentation slides. What material occurs at a depth of 10.0 m below the surface in the central drill hole of the three drill holes you were allocated? Refer to the previous site investigation report and provide a brief description of the geological characteristics of that material. Your description should be three to five sentences long. Use quotation marks if you are using the same words as in the report. Add this information to the bottom of your powerpoint slide. If you choose to add colour to the geological materials choose colours similar to those used in the Melbourne geology cross-sections provided, ensure that material codes are clearly visible and ensure that depth marks are visible. Restrict your graphic to a depth of -15m below sea level. The table below clarifies where the previous report uses different codes for similar materials. Code Unit name Previous report Fill Anthropogenic deposits Fill Qrs Swamp deposits Part of Qhi Qri Coode Island Silt Qhi Qrp Port Melbourne Sand Qpp Qrp1 Port Melbourne Sand with lenses of peat Part of Qpp Qrp2 Port Melbourne Sand with carbonate cement Part of Qpp Peat Organic deposits Part of Qpfl and Qpfu Qpf Fishermens Bend Silt Qpfl and Qpfu Qpf1 Fishermens Bend Silt with lenses of sand Part of Qpfl and Qpfu Qpg Moray Street Gravels Qpg Tpb Brighton Group Tpb Tvow Older Volcanics (weathered) Part of Tvo Tvo Older Volcanics (fresh) Tvo Tew Werribee Formation Tew Sud Melbourne Formation Sud GEOM2131 Geology: Assignment 1 Marking rubric Criteria Mark allocation Level 0 Level 1 Level 2 Level 3 Level 4 Level 5 Marks 2 /10 0 2 1. Accurately and clearly transferred drill hole data from spreadsheet to graphical format at correct scale Errors observed No errors observed Marks 2 /10 0 1 2 2. Clear title, legend (key), lithology labels and scale shown on graphic Graphic is illegible and incomprehensible Graphic is partially unclear and/or incomplete Graphic is clear and complete Marks 2 /10 0 1 2 3. Geological interpretation accurately conforms to the depth and lithology data at drill holes Interpretation does not conform to data Minor failure of interpretation to conform to data Interpretation conforms to data Marks 2 /10 0 0.5 1 1.5 2 4. Geological interpretation shows a realistic, evidence-based distribution of lithology between and beyond drill holes Interpretation not realistic or evidence-based Few aspects of interpretation realistic and evidence- based. Many aspects of interpretation realistic and evidence- based. Interpretation realistic and evidence-based. But does not show good awareness of geological features Interpretation realistic and evidence-based. Shows good awareness of geological features Marks 2 /10 0 1 2 5. Brief Geological description of material occurring 10m below surface in central drill hole from previous report Incorrect material or incorrect description Error in choice of material or description Correct material and description See next page for Part B instructions and rubric GEOM2131 Geology: Assignment 1 Part B: Tunnel portal photo and field data analysis for rock mass strength You will be assigned a tunnel portal photograph with field data in the same format and methodology as the examples explained in class. You will need to be able to determine the following parameters to complete the assignment: 1. Geological Strength index (GSI)[providing the value to the nearest ‘0 or 5’] (using the methodology of Sonmez and Ulusay 1999) 2. Hoek-Brown strength of the rock mass at a given confining stress (3 sig. figs) 3. Classify the excavatability according to the methodology of (Tsiambaos. and Saroglou, 2010) 4. For the rock type in your example write a brief description of its geological origin. Provide a reference for your description. Marking rubric Criteria Mark allocation Level 0 Level 1 Level 2 Level 3 Level 4 Level 5 Marks 2 /10 0 2 1. Geological Strength index (GSI) Incorrect value provided Correct value provided Marks 3 /10 0 1.5 3 2. Hoek-Brown strength of the rock mass at a given confining stress Incorrect value provided Incorrect strength calculated but correct for the input values used Correct value provided Marks 3 /10 0 1.5 3 3. Classify the excavatability Incorrect classification provided Incorrect GSI used but correct classification for that GSI Correct classification provided Marks 2 /10 0 0.5 1 1.5 2 4. Geological origin of the rock type Incorrect answer Correct description but no reference provide Not clear but generally correct Comprehensible but not entirely clear or correctly referenced Well explained and referenced PowerPoint Presentation Annotated Site Photographs - Tunnel Portal Exercises GEOM2131 – GEOLOGY module Assignment 1 Part B The following pages each contain a photograph of a tunnel portal together with relevant data. The data can be used to make an estimate of the rock mass strength using the Hoek-Brown method. The data also allows excavatability estimation. You will be allocated one of the tunnels as your data You will be allocated a confining stress to use in the rock mass strength calculation Instructions on methodology are provided in lecture slides Instructions for the assignment are provided on Canvas You are not required to do additional background research on the tunnel A submission template for the assignment is provided on Canvas Feature Data Width 7m Trend 300 Joint set 1 45-095 0.45m Joint set 2 62-224 0.85m Joint set 3 55-332 0.90m Joint condition Rough, moderately weathered, soft infill 2.5mm Rock type shale (medium) Melbourne Underground Rail Loop (MURL) portal under construction, late 1970s MURL Feature Data Width 4m Trend 300 Joint set 1 38-270 0.35m Joint set 2 15-035 0.8m Joint set 3 72-145 0.95m Joint condition Slickensided, moderately weathered, soft infill 1mm Rock type crystalline limestone (strong) Luck Stone Inspected tunnel connects two quarries at the Luck Stone Corporation Fairfax plant. The tunnel crosses beneath the Lee Highway (US Route 29), in a North-South direction. Built ca. 1975, the tunnel is partially unlined and in rock; approx. 190 feet long and approx. 22 feet wide and 22 feet high. As the Northern quarry side is already exhausted, the tunnel is rarely used with just one or two transits per day. Feature Data Width 7m Trend 240 Joint set 1 42-100 0.4m Joint set 2 60-217 1.0m Joint set 3 51-350 1.2m Joint condition Rough, highly weathered, soft infill 2mm Rock type siltstone Cheyenne Mountain Tunnel entrance to the Cheyenne Mountain Complex, Colorado Feature Data Width 6m Trend 040 Joint set 1 77-342 0.55m Joint set 2 80-082 1.3m Joint set 3 35-182 2.1m Joint condition Smooth, fresh, no infill Rock type greywacke Peru The Punta Olimpica Tunnel lies at an altitude of 4,738m above sea level. It has a total length of 1,380m and has been constructed in particularly challenging conditions. The altitude places high stress levels on equipment as the thin air means diesel engines and electric motors are more prone to overheating and cannot be loaded as heavily as at lower altitudes. Feature Data Width 11m Trend 060 Joint set 1 57-295 0.3m Joint set 2 30-095 0.7m Joint set 3 65-015 0.9m Joint condition Slickensided, moderately weathered, soft infill 1mm Rock type hornfels India Chenani-Nashri Tunnel (Patnitop Tunnel), India The Patnitop Tunnel became the longest road tunnel in the country when opened for traffic in 2017. Feature Data Width 12m Trend 120 Joint set 1 47-100 0.3m Joint set 2 45-210 0.8m Joint set 3 55-360 0.8m Joint condition Very rough, slightly weathered, soft infill 1mm Rock type andesite Harpers Ferry B&O Railroad Tunnel near Harpers Ferry, West Virginia Feature Data Width 3m Trend 230 Joint set 1 40-110 0.5m Joint set 2 65-212 1.4m Joint set 3 59-342 1.3m Joint condition Smooth, moderately weathered, soft infill 2mm Rock type amphibolite Paw Paw Tunnel The Paw Paw Tunnel was constructed through a steep topographic ridge now called Tunnel Hill. When work began on the tunnel in 1836, the builders estimated the project would be complete within two years. The tunnel ultimately required 14 years to complete due to labour issues and violence, funding shortfalls, work stoppages, and the challenges of digging through the hard, loose shale. The tunnel opened in October 1850 with rock slides continuing to be a challenge throughout the tunnel’s history. Feature Data Width 4.5m Trend 345 Joint set 1 36-110 0.5m Joint set 2 68-215 1.3m Joint set 3 50-340 1.4m Joint condition Smooth, slightly weathered, hard infill 3mm Rock type Sandstone (strong) Western Australia The underground portal at RNC Minerals' Beta Hunt mine in Kambalda,