Lecture 05 survey Engineering скачать в хорошем качестве

Lecture 05 survey Engineering

This video, part of a "Survey Engineering" series, focuses on discussing frequently asked questions from previous topics like introduction, classification, and chain survey (0:01-0:17). The questions are drawn from various competitive exams like GATE, SSC JE, and JKSSB (0:24-0:32). Key topics and questions covered include: Smallest Scale: The video explains how to identify the smallest scale among given options, highlighting that a larger denominator indicates a smaller scale (1:23-2:40). Fundamental Principle of Surveying: The "working from whole to part" principle is discussed, emphasizing its role in preventing the accumulation of errors (2:52-4:14). Geodetic vs. Plane Surveying: The key difference, which is the consideration of Earth's curvature in geodetic surveying, is explained (4:18-4:59). Types of Surveys: The video defines and gives examples of topographic surveys (5:03-5:42), cadastral surveys (5:21-5:26), and other survey types (5:27-5:33). Chain Survey Fundamentals: Gunter's Chain: Its length (66 feet) and number of links (100) are specified (6:47-7:23). Links in Metric Chains: The number of links in 20-meter (100 links) and 30-meter (150 links) chains is provided (7:26-7:52). Well-Conditioned Triangle: The criteria for angles in a well-conditioned triangle (not less than 30° and not more than 120°) are detailed (7:56-8:50). Area Division in Chain Survey: The video explains why areas are divided into triangles in chain surveying (8:53-9:35). Tally in Chain: The placement of tallies at every 5 meters in both 20-meter and 30-meter chains is explained (9:38-10:19). Corrections in Chain Survey: Chain Length Correction: Discusses the effect of a chain being too long on measured distance and the nature of the error and correction (10:24-11:19). Slope Correction: The approximate formula (h²/2L) and its always subtractive nature are explained, along with the exact relation (11:21-13:00). Sag Correction: This correction is always negative, and the reason behind it is explained (13:02-13:30, 25:01-25:47). Temperature Correction: The conditions under which temperature correction is positive (when field temperature is higher than standard temperature) and its formula are provided (13:32-14:17, 23:16-24:55). Pull Correction: The formula for pull correction (PM - P Not / AE * L₀) and its components are detailed (14:19-15:11). Instruments and Errors: Right Angle Instrument: The optical square is identified as the instrument used to set out right angles (15:35-15:53). Error due to Bad Ranging: This error is described as cumulative positive (16:01-16:27). Allowable Tolerance for Chains: Tolerances for 30-meter (+/- 8mm) and 20-meter (+/- 5mm) chains are provided (16:31-17:20). Offset: Defined as a lateral measurement from a chain line used to locate features (17:31-18:28). Normal Tension: Explained as the pull that neutralizes sag correction, resulting in zero net correction (18:40-19:54). Problem Solving: The video walks through an example problem of finding the true distance when a chain is too long (20:01-22:19)