The U.K.s second largest construction firm, Carillion, is set to go into liquidation under the weight of £1.5bn debt. Carillion, which employs approximately 20,000 people in Britain alone, is a key government supplier on the High Speed 2 (HS2) rail project and numerous education and health construction contracts. The group also maintains half of the U.K. and amp;#39;s prisons and is the second largest supplier to Network Rail