Stationing. Dumb question?

[NIKE]

Hey all, First time posting here.

I am a water resources guy studying for transportation breadth so some of you, broader, more enlightened civil engineers may think this is a dumb question...

I thought i understood stationing until i ran across a practice problem in some material a friend loaned me- 3.2 mi of roadway is what equivalent length in stations. The answer is 168.98 Sta NOT 168+96 Sta. Could someone explain when to use the XXX.XX format??

Thanks!

 

[wvgirl14]

Sta. 168+98 represents specific location or place. 168.96 Sta. represents distance.

 

[djgint]

NIKE,

It's not a dumb question. In fact this is a good AM question! When equivalent length is asked, the unit is located after the numerical value. So the equivalent length in stations for 3.2 mi. is 168.96 sta. 1 station is equal to 100 ft. When location is your intention, the unit is located before the numerical value (e.g. Sta 24+45). Example, an inplace density of base material is located at Sta. 24+45.

 

[NIKE]

Thank you both, makes perfect sense!

 

[ptatohed]

Hey all, First time posting here.

I am a water resources guy studying for transportation breadth so some of you, broader, more enlightened civil engineers may think this is a dumb question...

I thought i understood stationing until i ran across a practice problem in some material a friend loaned me- 3.2 mi of roadway is what equivalent length in stations. The answer is 168.98 Sta NOT 168+96 Sta. Could someone explain when to use the XXX.XX format??

Thanks!

What the others said is correct. 1 station is equal to 100 feet. So when asked how many stations are in (3.2mi x 5280ft/mi = ) 16,896 feet, you are being asked how many 100 foot-segments are in 16,896 feet? The answer of course is 16,896ft / 100ft/sta = 168.96 sta.

Conversely, if you were asked at what station a manhole 555ft upstream of Sta 0+00 is, your answer would be 0.00sta + 555ft / 100ft/sta = 5.55sta = Sta 5+55.

 

[solomonb]

I am NOT a civil engineer, but I find the discussion interesting. Please provide a SIMPLE example of the station construct!

 

[ptatohed]

I am NOT a civil engineer, but I find the discussion interesting. Please provide a SIMPLE example of the station construct!

Didn't we?

 

[solomonb]

Certainly, you did! Perhaps the question is better phrased on what determines the 100 foot increment per station? Is that definition? I am not playing with your mind, I am really asking an honest question!!!!!!!

 

[ptatohed]

Certainly, you did! Perhaps the question is better phrased on what determines the 100 foot increment per station? Is that definition? I am not playing with your mind, I am really asking an honest question!!!!!!!

No prob. Yes, the 100 feet is industry standard. The plans will show a street (but not always a street, it could be a storm drain, a wall, etc.) centerline (CL) alignment in plan view with the starting station usually selected at a convenient point, say an intersection between two streets near the beginning of the project. Then the stationing will increase as you head toward the end of the project limits. Stationing is almost always shown from left to right on the 24"h x 36"w sheet. As a general rule, stationing usually increases from west to east or from south to north (but not always). So, your north arrow will typically be up or to the right on your plan sheet. Storm drain stationing always increases from downstream to upstream regardless of direction (it's not uncommon to see a storm drain north arrow pointing down on the sheet). Back to the stationing..... the plans will including tic marks on the CL every 50 feet. The "half station" 50 foot tics are unlabeled. The full station tics every 100 feet are labeled. The beginning station is typically labeled a convenient station like 0+00 (or sometimes 10+00). The first 100 foot tic mark will be labeled "1+00", then another 100 feet upstation "2+00", and so on. It's not uncommon for the plan stationing to simply read "1", "2", etc. but it still means station 1+00, 2+00, etc. (100 feet upstation from 0+00, 200 feet upstream, etc.) So, to answer your question, yes, 100 feet between whole stations is typical convention.

Not to confuse you but.... the exception to this "100 foot rule" would be if your plans are metric. I don't have a lot of experience with metric plans but, if I remember correctly, one station is equal to 100 meters. Since this would result in a significant distance between stations, I think 20 meter tics/labels are included on the plans. So, a metric station of 205+20 would be 20,520 meters upstation of station 000+00. The next station on the plans would be 205+40, and so on.

Did that help? I probably answered w/ too much information and I made it confusing.

 

[John QPE]

Stationing is such an important concept to understand. It is so simple, but can really screw you in certain instances if you do not understand it, and a lot of people I have come across do not compeltely understand this concept. This was not a dumb question, this was a very important question.

 

[MWC PE]

Certainly, you did! Perhaps the question is better phrased on what determines the 100 foot increment per station? Is that definition? I am not playing with your mind, I am really asking an honest question!!!!!!!

No prob. Yes, the 100 feet is industry standard. The plans will show a street (but not always a street, it could be a storm drain, a wall, etc.) centerline (CL) alignment in plan view with the starting station usually selected at a convenient point, say an intersection between two streets near the beginning of the project. Then the stationing will increase as you head toward the end of the project limits. Stationing is almost always shown from left to right on the 24"h x 36"w sheet. As a general rule, stationing usually increases from west to east or from south to north (but not always). So, your north arrow will typically be up or to the right on your plan sheet. Storm drain stationing always increases from downstream to upstream regardless of direction (it's not uncommon to see a storm drain north arrow pointing down on the sheet). Back to the stationing..... the plans will including tic marks on the CL every 50 feet. The "half station" 50 foot tics are unlabeled. The full station tics every 100 feet are labeled. The beginning station is typically labeled a convenient station like 0+00 (or sometimes 10+00). The first 100 foot tic mark will be labeled "1+00", then another 100 feet upstation "2+00", and so on. It's not uncommon for the plan stationing to simply read "1", "2", etc. but it still means station 1+00, 2+00, etc. (100 feet upstation from 0+00, 200 feet upstream, etc.) So, to answer your question, yes, 100 feet between whole stations is typical convention.

Not to confuse you but.... the exception to this "100 foot rule" would be if your plans are metric. I don't have a lot of experience with metric plans but, if I remember correctly, one station is equal to 100 meters. Since this would result in a significant distance between stations, I think 20 meter tics/labels are included on the plans. So, a metric station of 205+20 would be 20,520 meters upstation of station 000+00. The next station on the plans would be 205+40, and so on.

Did that help? I probably answered w/ too much information and I made it confusing.

I've done one metric job and we used 1000m as a station (so exactly the same as a km) but it looked like 12+345. It was weird, I assume that is how it is done elsewhere but am not sure. This project was a legacy project from a brief experiment Tennessee DOT did in switching to metric in the 90s and then the project was shelved for a decade.

 

[MWC PE]

I've always looked at stations as convenience for plans, but have always done all math in feet. I just don't see any convenience in doing my math in stations.

 

[solomonb]

Thanks. I got it! I knew that it was not that complicated, however, needed some clarification-- you provided that. Thanks!

 

[NIKE]

wow, helpful folks on this board!