Using the Dumpy & Recording Levels M.S.Martin Aug – 2004 Revised Feb - 2006
Automatic Level / Dumpy Level Circular Bubble Eye Piece Sighting Pointer Horizontal Circle Focusing Knob Objective Lens Base Plate Foot Screw Fine Adjustment
Completed booking sheet example Rise & Fall method
Leveling equipment & booking sheets (take as written notes) An automatic level or alternatively a laser level, are the most common instruments used by builders to establish RL’s on a building site. To do this and for future reference, the levels you take on site should be recorded formally, from which you can transfer given RL’s into contour plans, calculate required cut & fill etc.
Notes continued Before we look at the level book, you should be aware and familiar with the following terms View through telescope Cross hairs Upper & lower stadia lines
Notes continued The view through the telescope is referred to as “the line of site” or “the line of collimation”
Notes continued • Terms: • BS – backsite • IS – intermediate site • FS – foresight • RISE – a change in height going up in level • FALL – a change in height going down in level • RL –reduced level • CP – change point • STN – station • BM – bench mark
Notes Continued • In reference to the use of instrument: • The first reading you take is always a B S backsite • The last reading you take is always a F S foresight • Readings in-between are I S intermediate sites