Cofferdams and Rockfill Embankments as Temporary River Diversion Structures-Challenges and Risks
In large hydropower projects rockfill embankments and cofferdams design and construction methodology, should focus on performance of foundation treatments during fiver diversion activities.The river diversion is a vital construction benchmark and it engages previous dee Phydrologie and hydraulic analysis and geologic-geotechnical investigations.Engineering experience on design and construction are mandatory and play an important role affecting timing, costs and safety in large dam projects.Two interesting cases of rockfi11 protection to overflow during flood period are mentioned in this paper.In spite of being temporary structures, rockfill cofferdams, must deserve previous deep analysis and design criteria experience by the designer and the Contractor.Unpredicted situations in fiver diversion, such as paleo-channel, rock fractures or alluvium sand/gravel matefials in foundation have been affecting construction schedule commonly, increasing treatment costs and quite often timing consuming and additional works.Some cases of cofferdam foundation treatment and zoning construction methodology are presented.Design optimization of temporary structures dimensions might be achieved whether overtopping is adopted as design criteria.Two examples of large rockfill dams where cofferdams and dam embankment protection facilities where designed and testing in hydraulic models during flood periods during construction are presented.After flood season and overtopping period, cleaning works at embankment areas were progressed and completed without delay construction schedule.
cofferdams foundation treatment overtopping rockfill reinforcement jet grouting
Manoel S.Freitas Guy H.R.M.Bourdeaux Xu Zeping
Av.Brig.Faria Lima No.2355 room 707-01452 000 S(o)o Paulo, SP, Brazil Brasil No.2433-Ilhote/ 11 630 000 Ilha Bela, SP, Brazil China Institute of Water Resources and Hydropower Research (IWHR) Beijing, P.R.China
国际会议
昆明
英文
742-753
2013-11-01（万方平台首次上网日期，不代表论文的发表时间）