Question
What are designing considerations for dowel bars in joints of concrete carriageway?
Answer
Behaviour of dowel bars resembles that of piles in soils subject to side loads. Breakdown of joint occurs by yielding of steel under bending action or by crushing of concrete due to manner stresses.
In universal, spacing of dowel bars has to not be too close that might pose trouble during construction. Though, it should be not also wide to allow occurrence of bending between dowel bars. On other hand, regarding length of dowel bars, it have to not be also long as induced stress at end of long dowel bars is insignificant and is not effectual in transferring loads between neighbouring concrete panels. Though, if dowel bars are too short, stress at the face of joint is increased resulting in concrete crushing.