Acceptability Criteria for Engineering Design工程设计可接受标准.ppt

Shear Strength of DiscontinuitiesSlope Stability Analysis Lecture 5 Earth 691B: Rock Engineering Outline Shear Strength of Discontinuities (Chapter 4, Hoek, 2000) Testing Field Estimates Sau Mau Ping Slope Example (Chapters 7 and 8, Hoek, 2000) Assumed shear strength values Test results Accounting for data variability Shear Strength of Joints Shear Strength of Joints Shear Testing Machine Shear Testing Machine Shear Strength of Saw Tooth SpecimenPatton (1966) Shear Strength of Discontinuities Influence of Scale on JRC and JCS Instantaneous Cohesion and Friction Instantaneous Cohesion and Friction Slope Stability Calculations Preliminary estimate of joint strength with sensitivity analysis of Factor of Safety (Recall from Lecture 2) Joint strength assessment from laboratory testing with Factor of Safety Calculation Using @Risk to include consideration of material variability Slope Stability Calculations Preliminary estimate of joint strength with sensitivity analysis of Factor of Safety (Recall from Lecture 2) Joint strength assessment from laboratory testing with Factor of Safety Calculation Using @Risk to include consideration of material variability Factor of Safety Against Sliding 14 foot tension crack half filled with water Earthquake acceleration = 0.08g Preliminary Field Estimate based on general published rock shear strength data: ? = 35, c = 10 FofS = 1.04 (used in Chapter 8) ? = 38, c = 12.5 FofS = 1.2 (interpreted from graph on previous page) Based on re-analysis with shear strength data from Hencher and Richards (1982): ? = 48, c = 0 FofS = 1.22 (as noted by Hoek, 2000) ? = 56, c = 0 FofS = 1.63 Slope Stability Calculations Preliminary estimate of joint strength with sensitivity analysis of Factor of Safety (Recall from Lecture 2) Joint strength assessment from laboratory testing with Factor of Safety Calculation Using @Risk to include consideration of material variability Probabilistic Analysis Definitions Probability Density Fun