Foreword

This standard is made according to the requirements of Notice on Printing the Development and Revision Plan of Professional Standards in 2007（Document No.1415，2007）issued by the National Development and Reform Commission.

Defects and aging of hydraulic concrete structure under the effect of load and environment have much influence on the safety and durability of the hydraulic concrete structure.In order to ensure a safe operation of hydraulic concrete structure，concrete detection shall be made regularly and irregularly and followed by safety assessment.This standard is made to make a better maintenance and management of hydraulic concrete structure，to regulate defect detection，assessment procedures and methods and to ensure safe operation and prolonging the lifespan of structure.

In preparation of this standard，relevant contents about detection and assessment in domestic and oversea standards was adopted to highlight the characteristics of hydraulic concrete structure and to cooperate with the relevant standards.On the basis of summering the practical experiences and research results，absorbing advanced technologies and collecting advices widely，technical requirements for detection and safety assessment of hydraulic concrete structure were proposed.

Appendixes C and D are normative.

This standard was proposed by China Electricity Council.

This standard is under jurisdiction and explanation of the Technical Committee of Standardization for Hydropower Construction of Electric Power Industry.

Main drafting organization:

　　　　　　China Institute of Water Resources and Hydropower Research（IWHR）.

Participant organization:

　　　　　　Beijing IWHR Technology Co.，Ltd，

　　　　　　Qingdao Pacific Marine Engineering Co.，Ltd.

Main drafters:

　　　　　　Lu Yihui　Sun Zhiheng　Yue Yuezhen　Zhang Jiahong　Xia Shifa

　　　　　　Xiao Liying　Wang Quanzeng　Shan Yuzhu　Li Xiulin　Yang Weicai

　　　　　　Zhang Fuchen.

Translated and examined by Sinohydro Corporation:

　　　　　　Zong Dunfeng　Xu Songling　Wang Yi　Chu Yuexian　Hou Yujing

　　　　　　Li Shisen　Cheng Jiansu　Wang Jinting　Yan Fuzhang　Kang Minghua

　　　　　　Li Jingshuang.