Leveling - Part 01 (Surveying)
LEVELING Important terminology 1. 1. Reduced level (RL) 2. 2. Mean sea level (MSL) 3. 3. Bench mark (BM) a. Permanent bench mark: - established by GOI, Indian railway, CPWD. b. Temporary bench mark: - e.g. change point Measurements in leveling work 1. Back sight reading 2. Fore sight reading 3. Intermediate sight reading Change point: - it is station or point after which instrument location is changed. At changed point first fore sight reading is taken from previous instrument and then back sight reading is taken from next instrument. Methods to find Reduced Level 1. Height of instrument (HI) method: - HI = RL of BM + BS, RL of any point = HI – IS/FS, check ∑ BS - ∑ FS = last RL – first RL 2. Rise and fall method: - rise/fall = previous reading...