Type and Shape Of Superstructure
In general, cast-in-situ solutions are considered more appropriate for this project in place of precast solution unless the site situation demands otherwise. This is due to the following reasons:
- The corridor passes through agricultural lands mostly and the cross drainage structures are mostly far away from the paved roads. it is felt that transportation of precast elements to the specific location would be difficult.
- Most of the bridges are of short to medium span range along the corridor and therefore for a specific site, the numbers of elements are not too many. This will entail a higher cost of transportation and launching.
Fig. Below shows the appropriate type of superstructure recommended for various span range.
Expansion Joints
Types of Expansion joints based upon the length of the span and movements are given below:
(i) For RCC slabs upto 11 m span only
Provide Buried type expansion joints
(ii) For all other bridges having span longer than 11 m and where movements are upto 70mm
Provide Elastomeric Single Strip Seal type expansion joints
(iii) Superstructure having movements more than +- 70mm.
Provide Modular Strip Seal expansion joints.
Drainage Spouts
Drainage spouts will be provided in accordance with MOST standard plans. The minimum spacing shall be kept preferably as 5.0m c/c which may be adjusted to suit span length. The drainage spouts at nallah/canal Bridge are proposed with free down fall.
Typical shape and dimensional details drainage spouts are shown in Fig.
Pot Ptfe Bearing Symbols
