Tags Building Materials 2015 (ContechMining 2015) commenced today at the Vietnam Exhibition Fair Centre ContechMining 2015 begins in Ha Noi Wednesday, Dec 02, 2015 The Viet Nam International Trade fair for Construction and Mining Technology, Equipment, Machinery, Building Materials 2015 (ContechMining 2015) commenced today at the Vietnam Exhibition Fair Centre (VEFAC) in Ha Noi.