Construction industry giant Strabag SE has acquired a German hydraulic engineering expert.The Vienna-based firm said yesterday (Weds) it fully took over Ludwig Voss GmbH retroactively on 1 January 2011, adding that it was awaiting the green light from competition watchdogs. Strabag did not disclose the takeover price.Ludwig Voss is a family business specialised in water engineering activities. The firm has its headquarters in the city of Cuxhaven which is located on the North Sea. Strabag explained the acquisition with the growing demand for hydraulic engineering work in Europe.News of the takeover came one day after Strabag and German rival Hochtief were assigned by the German traffic ministry to extend a 58-kilometre motorway stretch in the state of Bavaria.Affiliates of the firms will increase the number of lanes of the highway between the cities of Ulm and Augsburg to six and maintain the connection for 30 years. Around 410 million Euros will be invested, according to reports.The Romanian government said on Tuesday it assigned Strabag to construct a 24-kilometre stretch of motorway between Orastie and Sibiu in the south of the country for 134 million Euros.Strabag took over Swiss construction companies Brunner Erben Holding AG and Astrada AG last month, it has around 73,000 employees. The firm is headed by Hans Peter Haselsteiner. One Strabag share was traded for 23 Euros at the Vienna Stock Exchange (WBAG) at 11am today (Thurs), up from 21.80 Euros on 8 March.