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Hello Eveyone, I guess it does not matter what you call it ,if it can be mastered it saves time and money.
Running long level runs can take a lot of time., To insure they are correct they must be ran into a level loop. Sometimes bench loops are a costly procedure.Bench mark are not always close to the job. It also depend on what these elevation are used for and who is requiring them . What order and class they will fall into. lets just say these are third order , three wire. To save money and insure that they are correct, try the double rodding or double turns method .Whatever you call it. First you will need two good turns this can be metal pikes or long screwdrivers to use as turning points and of course a small hammer. You can use two rodmen or one good rodman . Level rod or rods and a rod bubble for each rod. First you will start at the BM ,most of the time there will be only one, if you do have two thats great ,if not you will have to make one more. so first do that make a TBM close to the BM and loop between them. Now you are ready to start you double rodding loop. also try to balance you shot on BS and FS distances . Have the rodman to pace his steps.Now here is the next trick have the rodman to set one turn higher or lower than the other turn and kept this shot order the same. If the turn on his right is first and higher keep it in this order. We will call it " A " because you will shoot this turn first and the lower on the left it will be " B ". So come off your BM and TBM called the BM A and the TBM B have the rodman set TP A and TP B shoot A and shoot B, now your ready to pick up and move to the next setup .Set the level up at the balance distance and shoot TP A record it , the same for TP B and move you rod man ahead and set TP A and TP B again shoot TP A and TP B, Remember what I said about High and low because this will help you not to make a mistake on what turns you are shooting also the one on the right first then the one on the left next,and by looking at the elevations you will know which is which. Repeat this until you reach your new BM site as before set a BM and a TBM. Because now you will set the BM A 2 and the TBM B 2 then tie between them to close the loop. If you do not set, but only one, then there will only be one shot to the one BM off of the two HI's this will not prove your last shot was a closer.You must tie between these two to make the loop. By learning how to do this method you will only have to walk this long distance one time, if not you will walk it twice. and twice the time.The notes can be kept together or in two different books or on two different clip boards. Whatever you decide and like. This method can be found in many survey manual.
BIlly
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In Today's survey world ,Modern methods have over come a lot of yesterdays, But still using a level is the only reach out and touch tool in the real world of all this science today .Surveyors have come to accept many of their electronic devices as hard proof of there angles ,distances or coordinates that replaced a real vernier for angles, a real tape or chain to measure with, and a real level to measure elevation with. Out of all the old methods and the modern one's, the level is the only way today in surveying to exceed ( First Order Elevation) ,this alone keeps it in the running with all the other methods in today's world..In this discussion I have talk about using two turns on a level run, to save time and money. If you don't like this method,you can loop between each turn closing the loop before you move to the next turn .this method will require you have two rod men or this would take too much time ,but looping your turns with two rod men is faster than running both direction ,there and back for a closure. Hope this Helps
Billy
Hello Everyone, Todays surveyors are equipped with more than a optical levels of yesterday. Even they are more advanced than what they were.Some have power optics to automatic electric focus similar to modern cameras to power focus.Some are just simple automatic levels even this is more advance than the Dumpy level of yesterday. There is also the geodetic tilting levels like Leica N3,then you have the most advance, Digital electronic levels. Then there are of course the laser levels,use manly by builders,. we won't go there. I like to talk about the digital level, It is also a automatic level, it is the most advanced and can be the most accurate.in some cases. but it is still a level when compared with a Total Station or GPS and it can be the most accurate between them. Some have cameras. In fact It can do a lot . Knowing the distance to keeping notes ,a wide array of things it can do.But it does have it down falls. So read these links and find out how accurate it is, the things it can do. and what is it's down falls.
Billy
http://www.sciencedirect.com/science/article/pii/S1018363910000048
http://www.sciencedirect.com/science/article/pii/S1110016812000075
Just like to add this link it goes over adjusting level runs and benchmarks. and a lot more on leveling.
http://www.tpub.com/inteng/7b.htm
http://engineeringtraining.tpub.com/14069/css/14069_487.htm
http://engineeringtraining.tpub.com/14069/css/14069_488.htm
http://engineeringtraining.tpub.com/14069/css/14069_490.htm