Council Leader Councillor Ian Miller joined local councillors watching the beams being put in.
He said: “The completion of the works at Cray Bridge will be a major improvement for road users travelling in this area, making their journey a safer one.
“This is a long-standing project which I am pleased the council has been able to take forward, making a significant and vital investment in infrastructure here in East Perthshire. It is excellent to see that the bridge replacement is progressing on schedule.”
Councillor Bob Ellis added: “I was particularly pleased to see this project go ahead as it has always been a difficult bridge to negotiate for the larger vehicles that transport goods to residents, farmers and land owners on the north side of Mount Blair.
“If this work hadn’t been done, then the council may have had to put a weight limit on the bridge.”
There are plans for the road to re-open in November.