A total of 71,647 days were lost to industrial disputes last year, according to new figures from the Central Statistics Office.
This compares with 32,964 days lost in 2015, the CSO said.
Two disputes in the education sector accounted for 76.2% of the days lost last year - 54,562 of the 71,647 total days lost.
The CSO noted a total of ten industrial disputes in 2016 compared with nine in 2015.
These ten disputes involved 29,372 workers and ten firms, whereas 37,760 workers and nine firms were involved in industrial disputes in 2015.
Last year saw strikes at secondary schools nationwide, Dublin Bus, Dublin's Luas system and Waterford airport.
