The discussion revolves around the procedures for leveling in surveying, specifically whether leveling must start and end at a benchmark or temporary benchmark of known elevation. Participants explore different methods and their implications for accuracy and error checking in leveling work.
Participants express differing views on whether leveling must start and end at a benchmark, with some supporting the flexibility of starting from any known elevation while others emphasize the reliability of returning to a benchmark for error checking. The discussion remains unresolved regarding the necessity of benchmarks in all leveling procedures.
Some limitations include the dependence on definitions of benchmarks and the potential for measurement errors in different leveling methods. The discussion does not resolve the mathematical or procedural nuances involved in these methods.
How about leveling start from known point to unknown point and back to known point? known point here means the point where the height is knownNidum said:Levelling around a survey route from one fixed bench mark and back to the same bench mark provides a very reliable means of error checking . If the cumulative changes in elevation around the survey route amount to zero when you get back to the known bench mark then the probability of having made measurement mistakes somewhere along the way is very small .
chetzread said:How about leveling start from known point to unknown point and back to known point? known point here means the point where the height is known
sorry , i mean how about levelling work start from a point where the height is known (benchmark) , and ends at a different point where the height is unknown ...Nidum said:That is effectively the same thing . You can designate any fixed level as your benchmark level .
When levelling over relatively short distances - on for example a construction site - the simpler method of starting from a bench mark and just proceeding in one direction is sometimes used .
Modern laser surveying methods and coming of GPS have made most of the traditional surveying methods obsolete .
Can you explain further ?Nidum said:That is effectively the same thing . You can designate any fixed level as your benchmark level .
When levelling over relatively short distances - on for example a construction site - the simpler method of starting from a bench mark and just proceeding in one direction is sometimes used .
Modern laser surveying methods and coming of GPS have made most of the traditional surveying methods obsolete .