GB 17741-1999 Technical specification for earthquake safety assessment of engineering sites
Some standard content:
IC891-120-25
National Standard of the People's Republic of China
GB177411999
Technical Code for Seismic Safety Evaluation of Engineering Sites
Published on April 26, 1999
Implemented on November 1, 1999
National Quality and Technical Appraisal Bureau
GB177411999
2 Reference Standards
Amount of Site Safety Evaluation Work Calculation
Activity of Area Power Covering and Newest Duck Construction
Near Field and Area Seismicity and Seismic Structure Seismic Spare Parts for Site Engineering||tt| |Relationship between earthquake intensity and earthquake risk
Deterministic analysis of earthquake risk
Probabilistic analysis of earthquake risk·
Regional earthquake zoning
Site earthquake risk assessment and geological hazard assessment
TKANKACa
GB177411999
This standard is formulated based on the current safety evaluation standards for engineering sites in China and the experience gained since its implementation in 1999. The main purpose of formulating this standard is to implement the laws of the People's Republic of China and do a good job in the safety evaluation of engineering sites and regional development.
When formulating this standard, we widely consulted with the opinions of the engineering community, technical experts and management experts in the field, as well as members of the National Earthquake Strength Determination Committee.
This standard was proposed by the China Earthquake Products Association, the Institute of Geophysical Research, the Institute of Geotechnical Engineering, and the Institute of Engineering Mechanics of China. This standard mainly refers to the technical requirements and technical methods for seismic safety evaluation of engineering sites
GB17741-1999
This standard specifies the technical requirements and technical methods for seismic safety evaluation of engineering sites and is applicable to the construction of new, expanded and rebuilt large-scale mining enterprises, cities and economic development zones to determine the requirements for seismic defense and safety, formulate development plans and seismic cost prevention measures. 2 Referenced standards
The following international standards contain multiple documents that are referenced in the standards and become non-standard standards. When the standards are published in the standard, the average values shown are included. All standards will be revised at will. All parties using the standards are advised to use the latest version of the following standards at will. GB50267—1997 Code for Design of Hydraulic Foundations of Power Plants GB17-1989 Code for Design of Foundations of Buildings JGJ83—1991 Code for Design of Foundations of Soft Soil Areas This standard adopts the following definitions 31 Background ground background A quantity that is not a structural quantity in a certain area 32 Site-specific response spectrum A response spectrum that takes into account the ground environment and site conditions 33 Seismic belt A quantity that is generated by earthquakes and is related to the ground 34 Earthquake inherent gravitational disturbance The damage caused by deformation or rupture of a geological body under the action of the earth 35 Geological motion ground motion pe rameter A physical parameter that causes ground motion, including the degree of deformation, response, etc. 36 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 38 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 39 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 40 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 41 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 42 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 43 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 44 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 45 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 46 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 47 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 48 Seismic tectonic zone is a geographical area with the same geological structure and similar activities. 39 oismc region
A region with uniform seismicity and tectonic conditions3 10 active fault sectionaetvelault smntApproved by the State Administration of Quality and Technical Supervision on April 26, 1999YYKANIKACa
Implementation on November 1, 1999
GB17741-1999
A section with uniform activity history, morphology, properties, seismic activity and dynamic characteristics in an active stratum311 special structureanalog
A method of analyzing seismicity, which believes that areas with the same group of tectonic signs are likely to experience the same earthquake312 paleopnleoearthquake
A geological exposure without written records, discovered by geological methods313 active new stratummetive fault
a recent active stratum with uniform activity.
314 Active structures
Tectonic structures that have been active since the beginning of the last century, including active layers, active plates, active levees, etc. 315 Capble fault
Active faults on or near the surface that can cause significant displacement. 316 Lower limit earthquake hazard analysis The lowest level of earthquake risk in the analysis. 317 The area where there is no potential source zone for earthquakes. 3 18 Probability-consistent response speetrum The increase in the magnitude of the response at the same point in the same area under the same reliability level. 9 Magnitude interval
The same product of the decomposition in the analysis of earthquake risk. The most important 5 320 earthquake cable on the Rupper limit earthquakemagnitude in the geological belt grams in the most suitable area is the lip level. 4 special number
Feng standard adopted below to save number:
A one one first out of the store energy area point floor:
& one health service · grain Kangmei Ke Shu rate +
small one first in the heavy original area by Sixia yuan! My one one high on the next is not sure about the sex random pot of huge half degree bacteria model one one! A bone in the direction of the rain model! Le first, a potential source area, the first in the face of the love file of the annual average rate of the blessing of the most! Intensity envelope number
1—seismic network degree:
Quantity seismic line:
NaRequired level classification number:
N—total number of earthquakes in the exhibition area
PZ—seismic degree or seismic step value, etc., is a given value R, epicenter distance
R.RM), near field distance and high field distance
S—a local specific number:
—intensity grid map, set on the load stop time, intensity grid surface number, flat surface number, visual stop time
intensity envelope function descending section coefficient:
given seismic motion parameters!
Y Earthquake effect:
GB17741-1999
Y- Characteristic intensity including surface characteristics, can be annual and Z- Earthquake intensity or seismic motion number:
- Given earthquake component or seismic motion parameter6 possible main fault direction!
Uncertain random variables in regression analysis
- Standard deviation of attenuation relationship:
I am from the port in the epicenter area, the annual average occurrence rate of earthquakes of the 1st magnitude level, and the annual average occurrence rate of earthquakes of the 1st magnitude level in the seismic zone. 5. Classification of site safety evaluation work
The site safety evaluation work of the project site is divided into the following levels of work, which must be combined with the following safety requirements. 5.11 Level work includes reliability analysis and deterministic analysis of ground cover danger, dynamic fault determination, site seismic motion effect determination and site geological fire hazard evaluation. Applicable to major projects in major construction projects with high safety requirements. 5.Level 21 work includes earthquake hazard probability analysis and earthquake zone planning (China Earthquake Intensity Zoning Map (1990)) and the main engineering projects in major civil engineering projects in major cities, major economic development zones and schools in major areas above the 1990 level. Level 531 work includes geohazard rate analysis, site geological fire hazard assessment, and the main engineering projects in major construction projects other than level 1 and 120 in areas above the 1990 level. Level 54 work is based on the current China Earthquake Intensity Zoning Map (1990) Use Regulations. For those who need to conduct earthquake intensity review, the ground hazard probability analysis is carried out. Applicable to projects other than level 1 and general. 6. Seismicity and Earthquake Structure in the Region
61 Research Scope bzxz.net
6.1.1 The area of the region that has an impact on the seismic safety of the project site should not be less than 150km from the project site. 6.1.2 The scale of the regional maps should be 111 million. For maps with lower requirements, a smaller scale can be used. All maps should indicate the location of the site points.
6.2 Seismicity in the Region
62.1 The writing of the earthquake diary shall be based on the following principles: 1. Collect officially published earthquake diaries and earthquake data reports published by the geological department, and compile a regional earthquake diary. 2. The historical earthquake diary shall include all destructive earthquake events in the region since the beginning of the earthquake record. 1. The daily record of earthquakes in the region shall give the reliable data of all the events that have occurred since the establishment of the regional urban station. The lower the level of the area and the level of work, the higher the level of the area and the level of work. 6.2.2 The preparation of the morning and summer distribution map of the earthquake should follow the following provisions: 1. Prepare the historical distribution map of the earthquake volume recorded in the region, indicating the start and end years of the data; 2. Prepare the distribution map of the earthquake volume recorded in the region, indicate the location of the station and indicate the start and end years of the data; 6.23 The analysis of the spatiotemporal characteristics of earthquake activity should include the following contents: 1. Analysis of the spatial distribution of earthquakes at all levels during different time periods; 2. Analysis of the intensity of the earthquake volume; 3. The collection and analysis of the site intensity data of historical earthquakes; 4. TKNYKACa
63 District Land South Structure
GB177411999
631 Bank live real estate company set and existing loan materials purchase land matching organization country · China should include live to the domestic guests since the first park century activities of the listening to the residents and their biomass and sports characteristics! 1. Direction of modern tectonic stress field and its nature:
2. Analysis of the probability and deterministic analysis of the danger of earthquakes. 3. For faults with great potential, the following contents should be supplemented when the data are insufficient:
3. Segmentation of fault activity:
4. Analysis of the maximum intensity and magnitude of the earthquake in key areas. 5. A regional geodynamic model should be established. 6. It is advisable to collect existing data and prepare the following basic documents: 1. A regional tectonic unit map, and add a tectonic map when necessary: 1. Bouguer gravity anomaly map. When necessary, carry out topography or average gravity anomaly calculation, and prepare corresponding maps - aeromagnetic anomaly book. When necessary, carry out topography and internal calculation, and compile corresponding documents! 1. Earthquake structure map
64. Earthquake zone and zone division
641. Differences in geophysical and geophysical structure, differences in geotectonic and tectonic history, differences in geodynamic activity
642. Earthquake rates can be divided according to the following points:
Dispersion of earthquakes and active structures.
65 Comprehensive analysis of the structural characteristics of the urban area
651 According to the results of the work of each section 1 to 64 of the chapter, a comprehensive analysis of the structural characteristics of the urban area should be carried out, and the bottom level can be 6.7.8.
7 Near field and site area seismic activity and seismic structure 7.1 Study model map and national scale
7.11 Near field can be taken as the area within 25km of the project site and its outer area. 1, 1 and 1 level work must be carried out within this scope. Field investigation.
7.12 The site can be taken as the area within 5km of the project site and its outer area. The first level work must be carried out within this scope. Investigation and appraisal
7.13 Near field map and indoor distribution map scale should be 11.2 million, and the first level work must be 11.1 million. 7.14 For details of the activity, the scale of the geological map should be 1110-1150 and the ground map and the brush map should be 11100-1110007.2 Near-field earthquake activity
7.2.1 Select destructive earthquake analysis, directly include the following: a pair of known near-field earthquakes, re-confirm the location and intensity of all known earthquakes in the near field. For any earthquakes with insufficient evidence or with insufficient evidence, after information verification and on-site investigation, confirm the location and intensity of the earthquakes. The analysis of the relationship between earthquake activity and active structures should comply with the following provisions:--Make a distribution map of the epicenters and analyze its relationship with active structures! Level I work, repositioning of earthquake events 723 Near-field focal mechanism data, including small earthquake comprehensive fault surface solution data, should be used to analyze and zoning local tectonic stress fields. 7.3 Near-field and field area active structures
Detailed identification of major faults, including active age, movement characteristics segmentation 7.32 Surface samples should be collected to determine the age of fault activity. In Hengyi area, corresponding geophysical and geochemical methods should be used to explore the location of faults.
7.33 Direct collection of geomorphological data, analysis of modern tectonic activity characteristics 7.34 Level I work should conduct Quaternary geological and geomorphological surveys. The surface and plan views of the first geological structure should be presented to explain the characteristics of the first geological movement:
7.35 Level I work must identify active faults based on the 1.125 million geological map of the field area. 7.4 Comprehensive evaluation of geological characteristics of the near-field and site area 7.4.1 A tectonic map of the near-field should be prepared.
7.4-2 A comprehensive evaluation of the seismic characteristics of the near-field and site area should be made. 8 Site engineering seismic conditions
81 Site considerations
811 The site model map may be the model map of the engineering construction plan 81.2 The project plan should include or site investigation, collection, collation and analysis of engineering geological and hydrogeological, topographic and geological data. 83 Yingcheng distribution map drilling book map engineering geology zoning store 814 Drilling operation is recommended to comply with the following regulations
For level 1 work, the drilling depth must be suitable for bedrock or shear depth is greater than or equal to 0/$. For level 1 work, there should be no less than 100 holes reaching the bedrock or the shear depth is greater than or equal to 500 times/place. If the soil thickness exceeds 100, the final hole can be drilled at a place that meets the degree of protection required by the site ground reaction analysis: The drilling arrangement of the level 1 work site should be able to control the soil structure and different engineering geological units in the site, and the site can produce saturated soil in the site, adjust the groundwater level, use standard penetration effect, and have heavy clay content. Level 1 work must comply with the provisions of GB50267:
--In sites where soft soil collapse may occur, investigate the thickness distribution of the soft soil layer and the deformation characteristics of the soft soil layer formed over the past 20 years, and conduct analysis
--In sites where periodic expansion and ground fissures may occur, collect information such as topographic depth, rock weathering process, ancient Langzeng, ancient Qingpo, Jishangdao, etc.
--For sites that may be affected by sea shear and tide, collect data on the site and nearby ground The film data of the area is a pair of field dimensions that may produce fault activities under the action of single. Collect the influencing data such as layer distribution, production style, layer charge density, dislocation and constant point layer density
82 site king power generation domestic products
82 main power generation most·seat bag live under the inner shear McDonnell Douglas, shear visual quantity, show Ma Yongcheng beautiful guide curvature, the relationship between the instrument and shear strain is shown by the line, the specific requirements are as follows: 1. Layered shear liquid velocity measurement should be carried out, and the control points should be encrypted where the soil properties change! Level 1 work must carry out dynamic triaxial tests on different soil layers: Level I, Level ■ work should carry out dynamic triaxial tests on representative soil layers, 5
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GB177411999
82.2 If it is necessary to consider the vertical earthquake response, the relationship between the velocity, initial compression modulus ratio and axial strain, and the relationship between the ratio and axial stress should be obtained.
9 Relationship between earthquake intensity and ground motion reduction
91 Basic data
91.1 The seismic intensity data of the city and neighboring areas should be collected. 912 The strong signal data of the city and the year area should be collected. 9.2 Earthquake intensity reduction system
92.1. The earthquake intensity is in a decreasing relationship, and the Jinguo or Yang model can be used. Its form is IC+CM+CIg(R+R)+CR+e
earth intensity:
same return number, where one is 1.2.
M magnitude, magnitude,
R medium distance, km
Ro near field distance high saturation solid. km
random variable
9.2.2 When determining the modulus step number, it is advisable to use only the earthquake visibility data recorded by the instrument, 92.3 The earthquake intensity attenuation model should reflect the near-field intensity and be coordinated with the far-field visible model. (1)
92.4 If the earthquake intensity reduction relationship is adopted, the difference in the observed intensity of the earthquake axis is less than 100 degrees in the near place and close to zero degrees in the far place. 92.5 The selected earthquake intensity reduction relationship should be compared with the actual earthquake intensity data. 93 The bedrock seismic intensity reduction relationship
931 In the bedrock seismic intensity reduction model, the peak value of the electric current and the high temporary component of the response are considered in the large magnitude and high moment of the earthquake. The formula can be
IY-C+ CM+CM+CR+RM+CR+
RM-CeNpCM
In the formula, R is the near field distance from the high ground and the country in km
94Intensity envelope coefficient
941Intensity envelope coefficient should be composed of three stages: rising, leveling and falling, and its form can be, f)-
lexpe-
Intensity envelope coefficient:
time, S1
small intensity envelope coefficient rising stage stop time$! Intensity envelope coefficient leveling stage stop time, s: intensity envelope coefficient falling stage coefficient.
94.2 The relationship between the characteristic number of the intensity envelope and the level, distance and site conditions can be expressed in the following model: lgY.-C+CM+CIgR+C)+CS
In the formula, Y. is a parameter that characterizes the durability of the intensity envelope, which can be . or S is a site-specific parameter. The ground motion attenuation relationship of the base site Sm095 fast strong earthquake observation data in the region 23
-(4)
91 The ground motion attenuation coefficient of the study area can be determined based on the ground intensity attenuation relationship of the study area and the ground intensity and ground motion attenuation relationship of the reference area.
GB177411999
952 If the seismic intensity attenuation model is used, the ground motion attenuation relationship of the study area can be obtained by converting the long and short axes respectively. 953 The standard deviation of the conversion result should not be less than the standard deviation of the seismic motion attenuation relationship in the reference area. 954 When determining the seismic motion attenuation system in the study area, its reasonable generation should be compared with the attenuation relationship obtained by conversion.
10 Deterministic analysis of earthquake risk
10.1 Seismic structure method
10.1.1 Seismic zones should be divided according to seismic activity and geological structure. 10.1.2 The seismic active strata should be segmented according to the following factors: - Differences in morphology and structure
- Differences in mechanical properties (normal faults, run-off faults and combined faults); - Differences in seismic activity;
- Differences in development history!
-Differences in motion characteristics (generation or generation)-Differences in geophysical and optical data 10.1.3 The maximum local earthquake magnitude of each active fault segment should be determined based on the size, activity characteristics, activity scale, and the largest historical earthquake on the active fault segment.
10.1.4 The maximum local earthquake magnitude that is not related to the confirmed active fault in the seismic tectonic zone should be determined 10.1.5 The determination of the site seismic motion magnitude should comply with the following provisions:- Place each maximum local earthquake at the nearest point to the site within its possible occurrence range, calculate the seismic parameter value of the site, and consider the uncertainty of the relationship:
- Consider the near-field applicability of the electric attenuation system!- Take the maximum value of the calculated result as the seismic parameter determined by the seismic construction method 10.2 Historical earthquake method
10-2. The following should be used to calculate the maximum seismic parameter value of the site based on the attenuation relationship suitable for the local area for each historical earthquake. 10.2.2 The intensity value of the site shall be determined based on the records and data of the damage caused by each historical earthquake, and converted to the electric field according to the provisions of 85 of this standard. 10.2.3 The maximum value of the results calculated in 10.2.1 and 10.2.2 shall be taken as the maximum earthquake parameter determined by the historical earthquake method. 10.3 Determination of the results 10.3.1 The larger of the results of the earthquake tectonic method and the historical earthquake method shall be taken as the result of the deterministic analysis of earthquake hazard. 11.1 Division of earthquake source areas 11-1.1 The earthquake source areas shall be divided on the basis of earthquake belts or earthquake zones. 1-1.2 The following signs should be considered and combined with the comprehensive analysis results of regional earthquake tectonic structure obtained according to the provisions of 6.5 of this standard to divide the earthquake risk areas: - Epicenter of destructive earthquake!
A scattered earthquake and small-scale dense zone:
—Ancient earthquake relic section:
A characteristic section of the ground space distribution image: Fault activity section!
A late Quaternary fault depression:
A special part such as the landing, turning point or intersection of the active fault: TTKAONYKACA
GH17741-1999
Part of the structural and electrophysical field characteristics related to the ground. 1.3 The boundary of the source area should be determined based on the spatial distribution image of the earthquake and the characteristics of the earthquake structure. If the seismic motion attenuation relationship is used, the possibility of multiple directions of the seismic motion growth in each source area should be considered to determine its direction. 11.2 Determination of seismic activity parameters
11.2.1 Seismic activity parameters include: - Upper limit of magnitude of seismic zone
- Value of seismic activity zone:
Annual average occurrence rate of earthquakes in seismic zone: - Upper limit of magnitude in source area:
- Cumulative average annual occurrence rate of each magnitude level in source area! Together with the magnitude of earthquakes!
Background magnitude and annual average occurrence rate. 11.2.2 Determine the seismic activity of seismic zone according to the following provisions! - The largest magnitude of earthquakes and seismic objects in history are determined. When determining the value of seismic activity zone, the completeness, reliability, representativeness and necessary sample size should be considered! 11.2.3 The following provisions shall be made to determine the seismic activity parameters in the seismic source area according to the seismic activity potential and the average annual occurrence rate of the seismic zone. 11.2.3.1 The upper limit of the magnitude of the earthquake in the source area shall be determined by taking into account the following factors: 1. The maximum historical earthquake magnitude in the source area: 2. The result of structural analogy; 3. The intensity of ancient earthquakes: 4. The results of seismic activity. 11.2.3-2 The upper limit of the magnitude of the earthquake in the source area shall be divided into 95 levels. 11.2.3.3- The average annual occurrence rate of each magnitude level in the source area shall be determined according to the following formula: M DM,JM
In the formula, the average annual occurrence rate of earthquakes in the first magnitude level in the first potential earthquake zone is: the average annual occurrence rate of earthquakes in the first magnitude level in the first potential earthquake zone is: the weight coefficient of the average annual occurrence rate of earthquakes in the first magnitude level in the second potential earthquake zone is: The weight coefficient of the average annual occurrence rate of earthquakes in the first magnitude level should be determined according to the sufficiency of the scientific data in the source area and the probability of occurrence of earthquakes in the corresponding magnitude levels. 11.2.4 The background earthquake can be taken as the minimum value of the upper limit of the magnitude in the source area minus 0.5 level, its annual average occurrence rate can be calculated based on actual data.
11.3-Calculation of the rate of occurrence of ground hazard
11.3.1 The annual occurrence rate of site seismic intensity and seismic motion parameters should be calculated by the following formula P(z2)-1-exp
Where 2-the number of seismic steps or seismic intensity: E()
a given seismic motion parameter value or seismic intensity value! P(z) seismic intensity or running vibration parameter value is greater than or equal to a given Value of the bottle rate: (0) - the first potential source area of the direction of the main age of the water (7) GB177411999 A - the area of the ith earthquake in the seismic source area, m () - the first earthquake in the seismic area, the site specificity or seismic parameters exceed a certain value! NM magnitude classification number: Ns total number of earthquakes in the seismic area, 1 1-3.2 The number of points in the periodic response before calculation shall not be less than 15. 11-4 Uncertainty Correction
11-4.1 In the probability calculation of earthquake risk, the uncertainty correction of attenuation relationship can be carried out by the following formula: P(22)P(2le(ed
In the formula, the number of variables can be 3
The standard deviation of the attenuation coefficient!
The random variable of uncertainty in the regression analysis: e)--the bottle rate density bacterial effect
11.4.21 General work, also consider the form of other uncertainties. 11-5 Result presentation
11-5.1 The various conditions that play a major role in the site's geological hazard should be described in a table. (8)
11.5.2 According to the needs of the project, the electric vibration parameters or seismic intensity values of different years and different supersensitivity should be presented in the form of diagrams and tables. 12 Urban earthquake zoning
12.1 Basic provisions
12.1.1 The earthquake zoning map should be compiled based on the latest results of the earthquake hazard residual distribution. 12.1-2
12-1-6
The earthquake zoning map should be expressed in terms of earthquake intensity or seismic intensity. In this case, the area should be 10.5 million square meters, and the area should be built according to the existing construction of the seismic activity and seismic characteristics in Chapter 6 of this standard. The near-site exposed activity and ground structure work shall comply with the provisions of Chapter 1 of this standard and shall comply with the provisions of Chapter 2 of this standard, and shall be in accordance with the relationship between the seismic observation degree and the ground motion attenuation of the area. The spacing of the calculation control points shall not be greater than 0.1 in the geographical longitude and latitude. In areas with large result changes, the control points should be appropriately increased. 12.1.7
12-2 The concentration level of the result table
The maximum value of the seismic zoning map shall be determined according to the requirements of the project plan and the anti-seismic defense.
The seismic intensity zoning map should be constructed based on the zoning map of the whole area. It is advisable to use a dynamic increase of no more than 0. The minimum and maximum values should be marked on the map. When determining the zoning boundaries based on the calculation results, the following factors should be considered: the accuracy of the source area and the range of variation of the seismic activity parameters, and their impact on the results: the difference in topography and terrain
the accuracy of the seismic motion parameters,
12-2.5 The corresponding instructions for use should be written. 13 Site seismic intensity determination and earthquake geological hazard assessment: 1 Site seismic response classification
13-1.11, level 1 and level 2, if the ground, soil layer interface and foundation are relatively flat, a one-dimensional analysis model can be used. If the soil layer interface, foundation is not smooth or the surface undulation is large, a two-dimensional load cell analysis model KANKAC
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