Roadway design - typical sections

[PLSTR]

Hi,

Some agents want typical (cross) section ranges, from certain station to another. Due to variable element dimensions in a typical section, e.g. variable width of median, defining the section range often is quite arbitrary. Another example is whether the range should include intersection area.

Are there some principles or common practice to define the typ sec ranges?

Thank you.

PLST

 

[Drumchaser]

What I usually encounter is a typ section with a shldr or median that varies from say 0-16 ft... and this is expressed with-in a given range of stations.

<--------0'-16'-------->

Sta. 222+31 to Sta. 691+91

this is very helpful in calculating quantities as well as identifying what the rdwy is doing while identifying the pavement structure (exist. and proposed)

in my opinion including the rdwy. widths and lengths are essential to good typ sections

I would agree with your point on intersections....the plan and profile sheets usually fully encompass these.

hope this is what you were after

 

[gbam]

PLSTR - When we have a varying width with separate control we show the control locations on the typical section and call them out "see Geometric Control sheets"

 

[PLSTR]

Thank you for the answers.
Some varibles cannot be seen on the pln & prof, e.g. pav str, and has to be shown in the typ sec with clear range or limits, I guess.
Some variables such as ret wall height is generally shown in ret wall pln/prof, and I guess, may not be necessary to be an elements to define/determine the typ sec limits.

PLST

 

[hmcrae]

Each time you add, drop or transition a lane you should include each of those. This should include the beginning lane config, transitional (ie turn lane transition 0ft to 12ft), and final lane config. Don't forget to include any ditches your drainage will require in these typical sections. You will likely have a discussion with the contractor about adding a ditch if it is not shown.

 

[gbam]

In my opinion, Typical Sections should be just that "Typical". There should not be a need to to have a section to show each instance; that is what the plans are for. My thought is if you have a 5 lane section and four lane divided then you should only have two typs, one for each. Otherwise we get into preparing cross sections rather than plans.

We have moved away from showing ditches on the Typical Sections also. We now use seperate Ditch/Channel Typical Section sheet(s). This, of course depends on the number and type of ditches and channels.