The publication of the new Clause 12 Existing Bridge Evaluation of CAN3-S6-M78 Design of Highway Bridges marks a radical departure from the conventional format of bridge design codes. For the first time bridges may be evaluated on the basis of reliability or probability of failure. The philosophy of Clause 12, a guide to its use, the derivation of the theory, and a discussion of the various coefficients used in the clause are given.

The current practice of providing unobstructed uniform natural lighting in our public schools has led to the extensive use of long continuous glass areas sometimes extending the full length of the classrooms. This leaves very little if any wall area remaining to provide the necessary strength and rigidity to the building along its longitudinal axis.