Detail of SL 252-2017

Introduction of SL 252-2017

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. SL 252-2000 Standard for Classification and Flood Control of Water Resources and Hydroelectric Project (hereinafter referred to as "the former standard") is revised in accordance with the formulation and revision planning of hydrotechnics standards and SL 1-2014 Rules for Drafting Hydrotechnics Standards. This standard, comprising 5 chapters, mainly covers the following technical contents: ——general provisions; ——terms; ——rank classification of water and hydropower projects; ——grade determination of hydraulic structures; ——determination of flood protection criteria of hydraulic structures. The following main technical contents have been revised this time: ——the chapter "terms" is added; the chapter "project rank and structure grade" in the former standard is classified into two chapters "rank of water and hydropower project" and "grade of hydraulic structure"; the chapter "building superelevation" in the former standard is cancelled; ——the flood control and water supply parameter system of "water and hydropower project rank parameters" in the former standard is adjusted partially; ——the requirements on rank parameters for barrage and irrigation & drainage pumping station specified in the former standard is adjusted; ——grade of hydraulic structure and flood protection criteria are adjusted partially; ——the requirements related to the level enhancement of permanent hydraulic structures like grade 2~5 high fill channel, wide-span or elevated platform aqueduct, high-head inverted siphon are added; ——relevant requirements on grades of permanent structure hydroelectric power house are determined by two conditions of water retaining and non-water retaining are added; ——relevant requirements on grade and design standard of dam with a maximum height exceeding 200m in reservoir works are added; ——relevant requirements on the flood protection criteria of reservoir having a control function in a cascade reservoir are added; ——relevant requirements on flood protection criteria for retaining dam as earth rockfill dam and concrete dam are added; ——relevant requirements on flood protection criteria of temporary water retaining facilities during diversion tunnel (bottom hole) blockage in reservoir works are added; ——relevant requirements on diversion design flood standard of temporary water retaining facilities at blockage engineering outlet during the construction period are added. In this standard, Articles 3.0.1, 3.0.2, 4.2.1, 4.3.1, 4.4.1, 4.5.1, 4.5.2, 4.5.3, 4.6.1, 4.6.2, 4.7.1, 4.8.1, 4.8.2, 5.2.1, 5.2.2, 5.2.7, 5.2.8, 5.2.10, 5.3.1, 5.3.2, 5.5.1, 5.5.3 and 5.6.1 are compulsory, written in bold type, and must be implemented strictly. The previous editions replaced by this standard are as: ——SL 252-2000 In the process of implementing this standard, all relevant organizations are kindly requested to sum up your experiences, accumulate information and feedback the relevant opinions and advice, whenever necessary, to the Department of International Cooperation, Science and Technology (correspondence address: No.2, 2nd Lane, Baiguang Road, Xicheng District, Beijing; post code: 100053; Tel: 010-63204533; E-mail: bzh@mwr.gov.cn) for future reference in revision. Contents Foreword i 1 General Provisions 1 2 Terms 1 3 Rank of Water and Hydropower Project 2 4 Grade of Hydraulic Structure 4 4.1 General Requirements 4 4.2 Grade of Permanent Hydraulic Structure in Reservoir and Hydropower Station Project 4 4.3 Grade of Permanent Hydraulic Structure in Barrage 5 4.4 Grade of Permanent Hydraulic Structure in Flood Control Project 6 4.5 Grade of Permanent Hydraulic Structure in Waterlogging Control and Drainage Projects 6 4.6 Grade of Permanent Hydraulic Structure in Irrigation Project 8 4.7 Grade of Permanent Hydraulic Structure in Water Supply Project 8 4.8 Grade of Temporary Hydraulic Structure 9 5 Flood Protection Criteria 10 5.1 General Requirements 10 5.2 Flood Protection Criteria of Permanent Hydraulic Structure in Reservoir and Hydropower Station Project 11 5.3 Flood Protection Criteria of Permanent Hydraulic Structure in Barrage 14 5.4 Flood Protection Criteria of Permanent Hydraulic Structure in Flood Control Project 14 5.5 Flood Protection Criteria of Permanent Hydraulic Structure in Waterlogging Control, Drainage, Irrigation and Water Supply Projects 15 5.6 Flood Protection Criteria of Temporary Hydraulic Structure 16 Explanation of Wording in This Standard 17 Standard for Rank Classification and Flood Protection Criteria of Water and Hydropower Project 1 General Provisions 1.0.1 In order to ensure the life and property safety of the people in water and hydropower projects and their lower reaches (protection areas) and the normal exertion of their benefits, this standard is formulated according to the national socioeconomic and scientific development level. 1.0.2 This standard is applicable to water and hydropower projects for purpose of flood control, waterlogging control, irrigation, water supply, power generation and others. If it is difficult to implement this standard for repair, reinforcing, renovation and extension of the existing water and hydropower projects, proper adjustment may be made upon sufficient argumentation and the competent authority's approval. 1.0.3 In classification of the rank of water and hydropower project, grade of hydraulic structures and flood protection criteria, relations between the local and the integral, the immediate interests and long-term interests, the upper reaches and lower reaches, the left bank and the right bank shall be appropriately handled. 1.0.4 For extremely important water and hydropower project with great scale and wider outreach, its rank, structure grade and flood protection criteria shall be determined through special argumentation upon the approval of the competent authority, if necessary. 1.0.5 Rank classification and flood protection criteria of water and hydropower projects shall not only meet this standard, but also comply with those in the national current relevant standards. 2 Terms 2.0.1 Rank of water and hydropower project rank of water and hydropower project classified by its scale, efficiency and significance in economy and society 2.0.2 Grade of hydraulic structures grade of hydraulic structure classified by its project rank, function and significance 2.0.3 Flood protection criteria scale of flood defensive for protect safety of hydraulic structure, divided into design flood criteria and checking flood criteria, generally expressed by flood at a frequency or with a recurrence interval 2.0.4 Permanent hydraulic structures hydraulic structures that are under long-term usage during its engineering utilization 2.0.5 Temporary hydraulic structures hydraulic structures that are only used in work construction and maintenance period 2.0.6 Main structures hydraulic structures that play a major role in the project, and will cause major disaster or have a strong impact on project benefit in case of accident 2.0.7 Secondary structures hydraulic structures that play a minor role in the project and have a weak impact in case of accident 2.0.8 Equivalent economic scale the product of the GDP per capita and population size in the flood protected area. The GDP per capita in the flood protected area is the ratio of the GDP per capita in the flood protected area to the national GDP per capita 3 Rank of Water and Hydropower Project 3.0.1 Rank of water and hydropower project shall be determined according to Table 3.0.1, considering its scale, efficiency and significance in the national economy. Table 3.0.1 Rank Parameters for Water and Hydropower Projects Project Rank Project Scale Overall capacity of reservoir /108m3 Flood control Waterlogging control Irrigation Water supply Power generation Protected population /104 people Protected farmland area /104 mu Equivalent economic scale of protected area /104 people Waterlogging control area /104 mu Irrigation area /104 mu Significance of water supply object Annual diversion /108m3 Installed generating capacity /MW I Large scale (1) ≥10 ≥150 ≥500 ≥300 ≥200 ≥150 Especially important ≥10 ≥1200 II Large scale (2) <10, ≥1.0 <150, ≥50 <500, ≥100 <300, ≥100 <200, ≥60 <150, ≥50 Important <10, ≥3 <1200, ≥300 III Medium scale <1.0, ≥0.10 <50, ≥20 <100, ≥30 <100, ≥40 <60, ≥15 <50, ≥5 Relatively important <3, ≥1 <300, ≥50 IV Small scale (1) <0.1, ≥0.01 <20, ≥5 <30, ≥5 <40, ≥10 <15, ≥3 <5, ≥0.5 Common <1, ≥0.3 <50, ≥10 V Small scale (2) <0.01, ≥0.001 <5 <5 <10 <3 <0.5 <0.3 <10 Note 1: overall capacity refers to the static capacity of a reservoir below the highest water level; waterlogging control area refers to the design waterlogging control area; irrigation area refers to the design irrigation area; annual diversion refers to the design annual average diversion (withdrawal) of canal head in a water supply project. Note 2: equivalent economic scale of protected area is limited to protected urban area; multiple parameters of flood control and water supply may satisfy one item. Note 3: for determining the rank of a project according to the significance of the water supply object, this project shall be the major source for the water supply object. 3.0.2 As for multi-purpose water and hydropower project, its rank shall be determined according to the multi-purpose project with the highest rank when the ranks of the multi-purpose projects are determined according to the rank parameters are different. 4 Grade of Hydraulic Structure 4.1 General Requirements 4.1.1 Grade of permanent hydraulic structure in a water and hydropower project shall be determined by comprehensive analysis according to the project rank or the grade parameter of the permanent hydraulic structure. 4.1.2 In a multi-purpose water and hydropower project, grade of a single-function individual structure shall be determined according to its function and scale; grade of a multi-function building shall be determined according to the higher scale parameter. 4.1.3 As for Grade 2~5 main permanent hydraulic structure in a water and hydropower project causing a huge loss or having very serious impact in case of accident, its grade may be raised by one grade upon argumentation and the competent authority's approval; as for Grade 1~4 main permanent hydraulic structure in a water and hydropower project with low head and causing a small loss in case of accident, its grade may be reduced by one grade upon argumentation and the competent authority's approval. 4.1.4 As for permanent hydraulic structure like Grade 2~5 high fill channel, wide-span or elevated platform aqueduct, high-head inverted siphon, its grade may be raised by one grade upon argumentation, but its flood protection criteria shall remain the same. 4.1.5 If grade 2~5 permanent hydraulic structure adopts new structure or its foundation is under especially complex engineering geological conditions, its grade may be raised by one grade upon argumentation, but its flood protection criteria shall remain the same. 4.1.6 Grade of permanent hydraulic structure to cross embankment or canal shall not be lower than that of the corresponding embankment or canal. 4.2 Grade of Permanent Hydraulic Structure in Reservoir and Hydropower Station Project 4.2.1 Grade of permanent hydraulic structure in a reservoir and hydropower station project shall be determined according to Table 4.2.1 in consideration of the rank of its project and its significance. Table 4.2.1 Grade of Permanent Hydraulic Structure Project rank Main structure Secondary structure I 1 3 II 2 3 III 3 4 IV 4 5 V 5 5 4.2.2 Reservoir dam shall be classified as Grade 2 or 3 as specified in 4.2.1; if the dam height exceeds the parameters specified in Table 4.2.2, its grade may be raised by one grade, but its flood protection criteria may remain the same. Table 4.2.2 Grade Parameters of Reservoir Dam Grade Dam type Dam height /m 2 Earth-rock dam 90 Concrete dam, masonry dam 130 3 Earth-rock dam 70 Concrete dam, masonry dam 100 4.2.3 As for dam structure with a maximum height exceeding 200 m in a reservoir project, its grade shall be Grade 1 and the design criteria shall be determined by special study and argumentation and approved by the superior competent authority. 4.2.4 If permanent hydraulic structure power house in a hydropower station retains water jointly with water retaining structure in a reservoir project, grade of the former shall be consistent with that of the latter, and determined according to the requirements of Table 4.2.1. If permanent hydraulic structure power house in a hydropower station takes non-water-retaining task and has no impact on safety of water retaining structure in case of accident, its grade shall be determined according to Table 4.2.4 in consideration of its installed capacity of the hydropower station. Table 4.2.4 Grade of Permanent Hydraulic Structure In Hydropower House Installed generating capacity /MW Main structure Secondary structure ≥1200 1 3 <1200, ≥300 2 3 <300, ≥50 3 4 <50, ≥10 4 5 <10 5 5 4.3 Grade of Permanent Hydraulic Structure in Barrage 4.3.1 Grade of permanent hydraulic structure in barrage shall be determined according to Table 4.2.1 in consideration of the rank of its project. 4.3.2 Permanent hydraulic structure in a barrage shall be classified as Grade 2 or 3 according to Table 4.2.1; if their checking waterflood flow rates through sluice are greater than 5000m3/s and 1000m3/s respectively, and their grades may be raised by one grade, but their flood protection criteria may remain the same.

Contents of SL 252-2017

Foreword i 1 General Provisions 2 Terms 3 Rank of Water and Hydropower Project 4 Grade of Hydraulic Structure 4.1 General Requirements 4.2 Grade of Permanent Hydraulic Structure in Reservoir and Hydropower Station Project 4.3 Grade of Permanent Hydraulic Structure in Barrage 4.4 Grade of Permanent Hydraulic Structure in Flood Control Project 4.5 Grade of Permanent Hydraulic Structure in Waterlogging Control and Drainage Projects 4.6 Grade of Permanent Hydraulic Structure in Irrigation Project 4.7 Grade of Permanent Hydraulic Structure in Water Supply Project 4.8 Grade of Temporary Hydraulic Structure 5 Flood Protection Criteria 5.1 General Requirements 5.2 Flood Protection Criteria of Permanent Hydraulic Structure in Reservoir and Hydropower Station Project 5.3 Flood Protection Criteria of Permanent Hydraulic Structure in Barrage 5.4 Flood Protection Criteria of Permanent Hydraulic Structure in Flood Control Project 5.5 Flood Protection Criteria of Permanent Hydraulic Structure in Waterlogging Control, Drainage, Irrigation and Water Supply Projects 5.6 Flood Protection Criteria of Temporary Hydraulic Structure Explanation of Wording in This Standard