Study On Material Property Of Concrete And Temperature Control For The QingJu Water Power Station

The crack of the water conservancy project building of concrete, not only influences the appearance of the project and normal running, but also threatens the security of project and shortens the life-span of project. Many project questions are produced because of the crack both at home and abroad. Preventing hydro-structure from cracks has been a key problem in design and construction of water power engineering. Temperature control is the key to solve this problem.In recent years, with the flourishing development of the water power of our country and the need to the development of the West Regions,hydroelectric engineerings have the trend to huge storage, huge capacity and huge scale. And the high temperature of every dam site district and the temperature drops suddenly frequently, so temperature control stands out especially.The QingJu Water Power Station , With installed capacity of 128MW, normal water level of 262.50m(correspondingly reservoir storage1.17×108m3), is located in Nanchong of Sichuan province, Midstream of JiaLingjiang River. This project temporarily stores water by low gate dam. Base plate of gate dam belongs to huge volume concrete. So temperature control is also an important aspect for QingJu project.In this paper, referring to QingJu Water Power Station, temperature control analysis and study has been done: Study on the match ratio of the concrete andquestion of modifying of the special fine sand concrete to improve resisting ability ofsplitting of concrete; Study on the technology of the highly mixed fly ash to reducethe adiabatic temperature rise of concrete; In case of the condition of resisting splitting to allow, Study on the temperature control measure to strengthen and water the size of building, simplify the operational procedure , accelerate the construction speed, economize the expenses of the project.Some conclusions are drawn as following through analysis and research:1. Through rectifying finest sand character and concrete mix ratio test, anti-split capability of structure concrete is strengthen;2. Heighten ratio of fly ash in finest sand concrete is beneficial to temperature control of huge volume concrete.3. Temperature control measures are proposed to quicken construction schedule and to economize project investment. The floodgate dam is completed more than 6 months ahead of time in the original piano It can generate electricity about 500 million kw ahead of time,convert about 100 million yuan.4. Through the studies on temperature control, we shorten the total length of axis of the floodgate of releasing floodwater by 5.5 m, economize more than 10000 m3 concrete, convert more than 3 million yuan .The achievement in research is adopted by the designs and constructions for the QingJu water power station. Because the economic benefits are remarkable, the employer has given bonus. Besides, the achievement in research has been adopted in the other large volume hydro-structure.