Field Measurements: Determining Elevations and Angles with Statistical Analysis - Prof. Ra, Study notes of Civil Engineering

Download Field Measurements: Determining Elevations and Angles with Statistical Analysis - Prof. Ra and more Study notes Civil Engineering in PDF only on Docsity! CE 115 FIELD MEASUREMENTS Theory of Measurements and Errors (SG-3) Name: ______________________________ Please complete the following problems in pencil on engineering paper. Thought of the day: "Remove not the ancient landmark, which thy fathers have set." Proverbs 22:28 1) The elevation of a certain benchmark is to be determined in the field. Repeated leveling circuits are completed to determine this elevation. The results are: 305.25’, 305.21’, 305.23’, 305.82’ and 305. 22’. Compute the most probable elevation, standard error and standard error of the mean for these elevations. Hint: One or more of the elevations may be considered to be blunder(s) and should not be included in the calculations. Explain the significance of each computed value as it relates to statistical theory. Show all of your work by filling out the following table: Elevation Residual Residual2 2) Using the data in problem 1, determine the range within which measurements should fall (a) 50% of the time and (b) 90% of the time. Compute the percentage of values that actually fit within these ranges. 3) Specifications for measuring angles of a 12-sided polygon limit the total angular misclosure to 30”. How accurately must each angle be measured to meet these specifications?