The victim was killed in a farmyard close to Carrickmacross in Co Monaghan.
He has been named locally as 19-year-old Robert O'Reilly. It is understood that he is from a rural area on the Cavan and Meath border, close to Kingscourt and Kilmainham Wood.
The college student, who had just completed his first year, was working with a building contractor in a farmyard when the accident occurred shortly after 9am yesterday.
It is believed they were working on a new milking parlour when shuttering for a concrete wall came down on top of Mr O'Reilly.
"It happened shortly after 9am. He was taken to hospital in Drogheda where he died," a source said.
Local councillor Clifford Kelly said the dead man was from an agricultural background and that his father is a well-known beef farmer.
"He was a lovely young lad. Everyone in the area learned of his tragic and unexpected death with great sadness," he added.
Gerard Reilly is the secretary of the Cavan branch of Irish Creamery Milk Suppliers Association (ICMSA). He described it as a "dreadful tragedy".
"We would like to offer our condolences to the family," he added.
Emma Jane Hade