THREE-FOURTHS of construction workers are sweating in big Chinese cities, including Shanghai, without labor contracts, which means it is easier for their employers to stand them up in salary disputes, according to a survey by Peking University. The survey was based on an investigation of recent construction labor markets in Shanghai, Beijing, Chongqing and Shenzhen. It found that 75.6 percent of the construction workers, mostly migrants hailing from China's vast, less-developed rural regions, said they had not signed any recruitment contact. The absence of a formal contract puts workers at a disadvantage in getting timely payment for their jobs. Only about 6 percent of construction workers in Shanghai said their salaries were settled at the end of each month, about the same as the level in Beijing, the survey showed. The percentage is about 23 percent in Shenzhen. Shanghai Daily interviewed some major construction group managers in Shanghai and their statements echoed the finding. ...