Spirals

[Earle D. Knowles]

Has survcadd a way to enter spirals between to curves of differing radius?
I haven't found it.

Federal Highways plans typically show curve points (PC, PT, TS, SC, CS, and
ST) but not PIs. For purposes of layout, I want to build an alignment from
the plans, but am stymied where a CS is followed by SC.

Help!

[John Dickson]

The only time I saw a curve to spriral to curve was on a set of highway
plans prepared using Microstaion and Geopak. I even looked in some
surveying text books to try to find the formula to calc my staking data by
hand, but the books only gave information on standard roadway design which
has a tangent at one end and a circular curve at the other end of the
spiral. Other than Geopak I have not seen any software that constructs this
kind of spiral. If you find anything let me know, I hated going back to
the engineer and asking for help.

John

"Earle D. Knowles" <Gregory.Spurlock@gte.net> wrote in message
news:bijd5u$tji$1@update.carlsonsw.com...

Has survcadd a way to enter spirals between to curves of differing radius?
I haven't found it.

Federal Highways plans typically show curve points (PC, PT, TS, SC, CS,
and
ST) but not PIs. For purposes of layout, I want to build an alignment
from
the plans, but am stymied where a CS is followed by SC.

Help!