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.
According to the requirements of Document Jian Biao [2008] No. 102 issued by the Ministry of Housing and Urban-Rural Development-"Notice on Printing and Publishing the Development and Revision Plan of National Engineering Construction Standards in 2008 (first batch)", this code is revised from the former "Code for Design of Building Foundation" GB 50007-2002 by China Academy of Building Research jointly with all the organizations concerned.
During the preparation process, the drafting group finally finalized this code upon review based on extensive investigation and study, earnestly summarizing the practical experience, making reference to the foreign advanced standards, coordinating with relevant national standards and extensively soliciting for opinions.
This code comprises 10 chapters and 22 appendixes, with main technical content including general provisions, terms and symbols, basic requirements, geotechnical classification and index properties, foundation design calculation, foundation in mountain area, soft ground, foundation type, excavation engineering, inspection and monitoring.
The main technical contents revised in this code are:
1. Add the relevant content of excavation engineering in the design grade of foundation;
2. The design working life of foundation shall not be less than that of building structure;
3. Add the engineering definitions of peat and cumulosol;
4. Add resilience recompression deformation calculation method;
5. Add building anti-floating stability calculation method;
6. Add the design principles of soil-rock composite ground with rock face gradient greater than 10% and foundation soil thickness greater than 1.5m when the medium and underlying rock face is inclining in single direction;
7. Add the design content of rock foundation;
8. Add the principle of design of foundation for the site in karst region according to the karst development degree;
9. Add the calculation method for composite ground deformation;
10. Add the design requirements that the minimum ratio of reinforcement of spread foundation shall not be less than 0.15%;
11. Add the requirements for the shear bearing capacity calculation of oblique section when the short-side dimension of the spread foundation bottom is less than or equal to the column width plus 2 times the foundation effective height;
12. Adjust the settlement empirical coefficient through statistical analysis for pile foundation settlement calculation method;
13. Add the requirements that the excavation engineering featured by complex hydrogeologic conditions on site, high protection requirement for surrounding environment of foundation pit and Grade-A design grade shall be subjected to special design for underground water control in high underground water level area;
14. Add the engineering inspection requirements for ground treatment engineering;
15. Add the key points for horizontal loading test of single pile and key points for vertical pullout load testing of single pile.
In this code, the provisions printed in bold type are compulsory ones and must be enforced strictly.
The Ministry of Housing and Urban-Rural Development is in charge of the administration of this code and the explanation of the compulsory provisions; the China Academy of Building Research is responsible for the explanation of specific technical contents. During the process of implementing this code, the relevant opinions or advice, whenever necessary, can be posted or passed on to the national standard "Code for Design of Building Foundation" Administrative Group of China Academy of Building Research (address: No. 30, North Third Ring East Road, Beijing, 100013, China, Email: tyjcabr@sina.com.cn).
Chief development organization of this code: China Academy of Building Research
Participating development organizations of this code: CIGIS
Beijing Geotechnical Institute
China Southwest Geotechnical Investigation and Architecture Design Institute
Guiyang Architectural Design & Surveying Prospecting Co., Ltd.
Beijing Institute of Architectural Design
China Architecture Design and Research Group
Shanghai Xiandai Architectural Design Group Co., Ltd.
China Northeast Architectural Design & Research Institute
Liaoning Provincial Building Design & Research Institute
Yunnan Yicheng Architectural Design Company
Central-South Architectural Design Institute
Hubei Provincial Academy of Building Research
Guangzhou Academy of Building Research
Heilongjian Province Academy of Cold Area Building Research
Heilongjiang Province Building Engineering Quality Supervision Station
Northern Engineering & Technology Corporation, MCC
China State Construction Engineering Corp.
Tianjin University
Tongji University
Taiyuan University of Technology
Guangzhou University
Zhengzhou University
Southeast University
Chongqing University
Chief drafting staff of this code: Teng Yanjing, Huang Xiling, Wang Shuguang, Gong Jianfei, Wang Weidong, Wang Xiaonan, Wang Gongshan, Bai Xiaohong, Ren Qingying, Liu Songyu, Zhu Lei, Shen Xiaoke, Zhang Bingji, Zhang Chengjin, Zhang Jichao, Chen Xiangfu, Yang Min, Lin Liyan, Zheng Gang, Zhou Tonghe, Wei Wu, Hao Jiangnan, Hou Guangyu, Hu Daiwen, Yuan Neizhen, Gu Baohe, Tang Mengxiong, Gu Xiaolu, Liang Zhirong, Kang Jingwen, Pei Jie, Pan Kaiyun, Xue Huili
Chief examiners of this code: Xu Zhengzhong, Huang Shaoming, Wu Xuemin, Gu Guorong, Hua Jianxin, Wang Changqing, Xiao Ziqiang, Song Zhaohuang, Xu Tianping, Xu Zhangjian, Mei Quanting, Huang Zhihong, Dou Nanhua
Contents
1 General Provisions 1
2 Terms and Symbols 1
2.1 Terms 1
2.2 Symbols 2
3 Basic Requirements 3
4 Geotechnical Classification and Index Properties 8
4.1 Geotechnical Classification 8
4.2 Engineering Index Properties 11
5 Foundation Design Calculation 12
5.1 Embedded Depth of Foundation 12
5.2 Bearing Capacity Calculation 15
5.3 Deformation Calculation 19
5.4 Stability Calculation 24
6 Foundation in Mountain Area 26
6.1 General Requirements 26
6.2 Foundation on Rock and Soil 26
6.3 Foundation on Compacted Fill 28
6.4 Landslide Prevention 30
6.5 Foundation on Rock 32
6.6 Karst and Sinkhole 32
6.7 Earth Slope and Gravity Retaining Wall 35
6.8 Rock Slope and Anchor Wall 40
7 Soft Ground 42
7.1 General Requirements 42
7.2 Usage and Treatment 43
7.3 Architectural Measurement 45
7.4 Structural Measurement 46
7.5 Massive Ground Surcharge 47
8 Foundation 49
8.1 Non-reinforced Spread Foundation 49
8.2 Spread Foundation 50
8.3 Strip Foundation under Columns 60
8.4 Raft Foundation of High-rise Buildings 61
8.5 Pile Foundation 71
8.6 Rock Bolt Foundation 84
9 Excavation Engineering 85
9.1 General Requirements 85
9.2 Excavation Engineering Exploration and Environmental Investigation 87
9.3 Earth Pressure and Water Pressure 88
9.4 Design Calculation 89
9.5 Internal Bracing of Support Structure 90
9.6 Soil Bolt 91
9.7 Excavation Engineering Inverse Practice 92
9.8 Excavation Engineering of Rock Mass 94
9.9 Underground Water Control 94
10 Inspection and Monitoring 96
10.1 General Requirements 96
10.2 Inspection 96
10.3 Monitoring 99
Appendix A Division of Rock Hardness and Rock Mass Integrity Degree 101
Appendix B Field Identification of Gravel Soil 102
Appendix C Key Points for Shallow Plate Load Testing 103
Appendix D Key Points for Deep Plate Load Testing 104
Appendix E Standardized Value for Shear Strength Parameters C and 105
Appendix F Contour of Seasonal Standardized Frost Depth in China 107
Appendix G Classification of Soil Expansion upon Freezing and Maximum Allowable Thickness of Frozen Earth above Building Foundation 108
Appendix H Key Points for Loading Test on Rock 111
Appendix J Requirements for Uni-axial Compressive Strength Testing on Rock 113
Appendix K Stress Influence Coefficient α and Average Stress Influence Coefficient 114
Appendix L Active Earth Pressure Coefficient ka for Retaining Wall 128
Appendix M Key Points for Pullout Resistance Testing on Rock Anchors 134
Appendix N Calculation of Subsequent Foundation Settlement under Massive Ground Surcharge 135
Appendix P Perimeter of Critical Section for Shearing and Polar Moment of Inertia Calculation 137
Appendix Q Key Points for Vertical Static Load Test on Single Pile 140
Appendix R Final Settlement Calculation for Pile Foundation 142
Appendix S Key Points for Lateral Load Test on Single Pile 147
Appendix T Key Points for Uplift Capacity Test on Single Pile 151
Appendix U Anti-shearing Sectional Width of Step and Cone-shape Pile Cap 154
Appendix V Stability Evaluation for Excavation Support Structures 156
Appendix W Anti-seepage Stability Evaluation for Foundation Pit 160
Appendix Y Key Points for Pre-stressed Earth Anchor Testing 161
Explanation of Wording in this Code 163
List of Quoted Standards 164
1 General Provisions
1.0.1 This code is formulated with a view to implementing technical and economic policies of the nation in foundation design, and achieving safety and usability, advanced technology, economy and rationality, quality guarantee and environmental protection.
1.0.2 This code is applicable to the design of foundation of industrial and civil buildings (including structures). The design of collapsible loess, permafrost and expansive soil foundation and the foundation under the action of seismic and mechanical vibration load shall also meet the requirements of the current corresponding professional standard of the nation.
1.0.3 The design of foundation shall persist in the principle of adjusting measures to local conditions, using local materials, protecting environment and saving resources, comprehensively consider such factors as structure type, material condition and construction condition according to geotechnical engineering investigation data, and elaborately conduct.
1.0.4 The design of building foundation shall not only comply with this code, but also those in the current relevant ones of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 Ground, foundation soils
Soil mass or rock mass which supports foundation.
2.1.2 Foundation
Structure component which transfers various actions borne by the structure to the ground.
2.1.3 Characteristic value of subsoil bearing capacity
Pressure value corresponding to deformation specified within linear deformation section of subsoil pressure deformation curve determined by load test, and its maximum value is the proportion limit value.
2.1.4 Gravity density, unit weight
Gravity borne by rock-soil mass per unit volume, the product of density and gravity acceleration of rock-soil mass.
2.1.5 Rock discontinuity structural plane
Plane which cracks and is easy to crack in rock mass, such as bedding surface, joint, fault, schistosity, etc., also called discontinuous structural plane.
2.1.6 Standard frost penetration
Average value of maximum frost penetration actually measured for more than 10 years in the flat and exposed open area outside the city.
2.1.7 Allowable subsoil deformation
Deformation control value determined in order to guarantee normal use of the building.
2.1.8 Soil-rock composite ground
Ground with larger underlying bed rock surface gradient within the range of main bearing layer of building ground; or ground with densely-spread and exposed clint; or ground with exposed mass boulder or individual clint.
2.1.9 Ground treatment, ground improvement
Engineering measures to be taken in order to increase subsoil bearing capacity or improve its deformability or permeability.
2.1.10 Composite ground, composite foundation
Artificial ground that subsoil and reinforcement formed by reinforcing or replacing partial soil mass jointly bear load.
2.1.11 Spread foundation
Foundation that spreads a certain base area to side edge in order to diffuse the load transmitted from superstructure to make the compressive stress acted on the base meet the design requirements of subsoil bearing capacity and the internal stress of foundation meet the design requirements of material strength.
2.1.12 Non-reinforced spread foundation
Strip foundation under wall or independent foundation under column, composed of such materials as brick, rubble, concrete or rubble concrete, dirt and cement and not reinforced.
2.1.13 Pile foundation
Foundation which is composed of pile arranged in rock-soil and slab connected to pile top end.
2.1.14 Retaining structure
Structure which is built to make rock-soil side slope remain stable, control displacement and mainly bear lateral load.
2.1.15 Excavation engineering
General term of retaining structure, underground water control, environmental protection and other measures required for guaranteeing underground space formed in downward ground excavation safe and stable during the construction period of underground structure.
2.2 Symbols
2.2.1 Action and action effect
Ea——Active earth pressure;
Fk——Value of vertical force, transferred from superstructure to foundation top, corresponding to the acting standard combination;
Gk——Deadweight of foundation and soil weight on foundation;
Mk——Value of moment acts on the foundation bottom, corresponding to the acting standard combination;
pk——Average pressure at foundation bottom, corresponding to the acting standard combination;
p0——Average additional pressure at foundation bottom;
Qk——Vertical force borne by single pile in pile foundation under the action of axial vertical force, corresponding to the acting standard combination.
2.2.2 Resistance and material property
a——Compressibility coefficient;
c——Cohesion strength;
Es——Compression modulus of soil;
e——Void ratio;
fa——Corrected characteristic value of subsoil bearing capacity;
fak——Characteristic value of subsoil bearing capacity;
frk——Standardized value of uni-axial compressive strength of saturated rock;
qpa——Characteristic value of soil bearing capacity of pile tip;
qsa——Characteristic value of frictional force of pile periphery soil;
Ra——Characteristic value of vertical bearing capacity of single pile;
w——Moisture content of soil;
wL——Liquid limit;
wp——Plastic limit;
γ——Gravity density of soil, referred to as unit weight of soil;
δ——Friction angle between fill and retaining wall back;
δr——Friction angle between fill and resistant rock slope surface;
θ——Pressure diffusion angle of ground;
μ——Friction coefficient between soil and retaining wall base;
v——Poisson's ratio;
φ——Internal friction angle.
2.2.3 Geometric parameters
A——Foundation bottom area;
b——Foundation bottom width (minimum side length); or foundation bottom side length of moment action direction;
d——Embedded depth of foundation, pile body diameter;
h0——Foundation height;
Hf——Building height counting from foundation bottom;
Hg——Building height counting from outdoor ground;
L——Building length or unit length separated by settlement joint;
l——Length of foundation bottom;
s——Settlement volume;
u——Peripheral length;
z0——Standard frost penetration;
zn——Calculation depth of ground settlement;
β——Slope angle of side slope to horizontal plane.
2.2.4 Calculation coefficient
——Average additional stress coefficient;
ηb——Correction coefficient of bearing capacity of foundation width;
ηd——Correction coefficient of bearing capacity of embedded depth of foundation;
φs——Empirical coefficient of settlement calculation.
3 Basic Requirements
3.0.1 The design of foundation shall be divided into three design grades according to ground complexity, building scale and functional characteristics as well as the degree of building damage or normal use influence caused by possible ground problems, and shall be selected in accordance with those specified in Table 3.0.1 according to specific conditions.
Table 3.0.1 Design Grade of Foundation
Design grade Building and ground type
Grade A Important industrial and civil buildings
High-rise buildings with more than 30 storeys
Combined high- and low-storey building with complicated shape and storey number difference exceeding 10
Extensive multi-story underground building (such as underground garage, shopping mall and sports ground)
Building with specific requirements for subsoil deformation
Building on slope (including high slope) under complicated geological conditions
Newly-built building with larger influence on existing engineering
General building with complicated site and ground conditions
Excavation engineering of basement of two-storey or above building in complicated geological conditions and soft soil area
Excavation engineering with excavation depth greater than 15m
Excavation engineering with complicated surrounding environment condition and high environmental protection requirements
Grade B Industrial and civil buildings beyond Grade A and Grade C
Excavation engineering beyond Grade A and Grade C
Grade C Seven-storey or below civil buildings and general industrial buildings with simple site and ground conditions and even load distribution; secondary light buildings
Excavation engineering in non-soft soil area, with simple site geological conditions, simple foundation pit surrounding environment conditions, not high environmental protection requirements and excavation depth less than 5.0m
3.0.2 The design of foundation shall meet the following requirements according to the design grade of building foundation and the influence degree of subsoil deformation under the action of long-term load on superstructure:
1 The foundation design calculation of all the buildings shall meet the relevant requirements for calculation of bearing capacity;
2 The buildings with a design grade of Grade A or Grade B shall be designed according to subsoil deformation;
3 The buildings with a design grade of Grade C shall be subjected to deformation checking under one of the following conditions:
1) Buildings with characteristic value of subsoil bearing capacity less than 130kPa and with complicated shape;
2) When there is ground loading on the foundation and neighborhood or the difference between the adjacent loads is large, and the ground may be caused to generate excessive nonuniform settlement;
3) When the building on soft ground has eccentric load;
4) When the adjacent buildings are close and may have inclination;
5) When there is relatively thick or uneven fill in ground and the deadweight consolidation is not completed.
4 For high-rise buildings, high-rise structure, retaining wall, etc. frequently subjected to horizontal load, as well as buildings and structures built on slope or near side slope, their stability shall also be checked;
5 Excavation engineering shall be subjected to stability checking;
6 When building basement or underground structure has floating upward problem, anti-floating checking shall also be conducted.
3.0.3 The buildings with a design grade of Grade C within the range listed in Table 3.0.3 may not be subjected to deformation checking.
Table 3.0.3 Range of Buildings with a Design Grade of Grade C not Subjected to Subsoil Deformation Checking
Conditions of main bearing layer of ground Characteristic value of subsoil bearing capacity
fak(kPa) 80≤fak<100 100≤fak<130 130≤fak<160 160≤fak<200 200≤fak<300
Gradient of each soil layer (%) ≤5 ≤10 ≤10 ≤10 ≤10
Building type Masonry bearing structure and frame structure
(layer number) ≤5 ≤5 ≤6 ≤6 ≤7
Single-layer bent structure (6m column space) Single-span Rated lifting capacity of crane (t) 10~15 15~20 20~30 30~50 50~100
Plant building span
(m) ≤18 ≤24 ≤30 ≤30 ≤30
Multi-span Rated lifting capacity of crane (t) 5~10 10~15 15~20 20~30 30~75
Plant building span
(m) ≤18 ≤24 ≤30 ≤30 ≤30
Chimney Height (m) ≤40 ≤50 ≤75 ≤100
Water tower Height (m) ≤20 ≤30 ≤30 ≤30
Volume (m3) 50~100 100~200 200~300 300~500 500~1000
Notes: 1 The main bearing layer of ground refers to the range with a depth of 3b (b is the foundation bottom width) under strip foundation bottom, 1.5b under independent foundation, and thickness not less than 5m (except the general civil buildings less than two storeys);
2 If the main bearing layer of ground has soil layer with characteristic value of bearing capacity less than 130kPa, the design of masonry bearing structure in this table shall meet the relevant requirements of Chapter 7 of this code;
3 Masonry bearing structure and frame structure in this table refer to civil buildings; for industrial buildings, equivalent storey number of civil buildings may be converted according to plant building height and load condition;
4 The value of rated lifting capacity of crane, chimney height and water tower volume in this table refers to the maximum value.
3.0.4 Geotechnical engineering investigation shall be carried out before the design of foundation and shall meet the following requirements:
1 Geotechnical engineering investigation report shall be provided with the following data:
1) Check whether there is adverse geologic action influencing building site stability and assess the hazard degree;
2) Stratum structure and its uniformity within building range, physical and mechanical property indexes of each rock-soil layer as well as corrosiveness for building materials;
3) Underground water embedment condition, type, water-level fluctuation amplitude and rule, as well as corrosiveness for building materials;
4) Classify site category in seismic fortification zone, and carry out liquification evaluation for saturated sandy soil and silty soil;
5) Demonstrate and analyze the available design scheme of foundation, and propose economic and rational and advanced-technology design scheme suggestion; provide subsoil bearing capacity and deformation calculation parameters corresponding to the design requirements, and propose suggestion for problems to be noticed in design and construction;
6) If necessary for engineering, provide: rock-soil technical parameters required for slope stability calculation and support design of deep foundation pit excavation, demonstrate the influence on surrounding environment; technical parameters related to precipitation in foundation pit construction and suggestion for underground water control method; fortification water level for calculating underground water flotage.
2 The ground assessment should adopt boring sampling, laboratory soil test, penetration test and combine other in-situ test methods. For the buildings with a design grade of Grade A, load test index, shear strength index, deformation parameter index and penetration test data shall be provided; for the buildings of Grade B, shear strength index, deformation parameter index and penetration test data shall be provided; for the buildings of Grade C, penetration test and necessary boring and soil test data shall be provided.
3 All the building grounds shall be subjected to construction and foundation subsoil inspection. Where the ground condition doesn't conform to the original investigation report, construction investigation shall be carried out.
3.0.5 In design of foundation, the adopted action effect and corresponding resistance limit value shall meet the following requirements:
1 When determining foundation bottom area and buried depth according to subsoil bearing capacity or determining pile number according to single pile bearing capacity, the action effect transmitted to foundation or slab bottom shall be in accordance with the standard combination acting in limit state of normal use, and the corresponding resistance shall adopt characteristic value of subsoil bearing capacity or characteristic value of single pile bearing capacity;
2 When calculating subsoil deformation, the action effect transmitted to foundation bottom shall be in accordance with the quasi-permanent combination acting in limit state of normal use and shall not be counted into wind load and earthquake action; corresponding limit value shall be the allowable subsoil deformation;
3 When calculating retaining wall, ground or landslide stability and foundation anti-floating stability, the action effect shall be in accordance with the fundamental combination acting in limit state of bearing capacity, but the partial coefficient shall be 1.0;
4 When determining foundation or pile foundation slab height, retaining structure section, calculating internal force of foundation or retaining structure, determining reinforcement and checking material strength, the action effect transmitted from superstructure and corresponding base counterforce, retaining wall earth pressure and landslide thrust shall be in accordance with the fundamental combination acting in limit state of bearing capacity, and the corresponding partial coefficient shall be adopted; if it is necessary to check the foundation crack width, they shall be in accordance with the standard combination acting in limit state of normal use;
5 Foundation design safety class, structure design service life and significance coefficient of structure shall be adopted according to the relevant specifications, but the significance coefficient of structure Υ0 shall not be less than 1.0.
3.0.6 In the design of foundation, the design value of the action combination effect shall meet the following requirements:
1 In limit state of normal use, the design value of the standard combination effect Sk shall be determined according to the following formula:
Sk=SGk+SQ1k+ψc2SQ2k+……+ψcnSQnk (3.0.6-1)
Where,
SGk——the effect of standardized value of permanent action Gk;
SQik——the effect of standardized value of the ith variable action Qik;
ψci——the combination value coefficient of the ith variable action Qi, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
2 The design value of the quasi-permanent combination effect Sk shall be determined according to the following formula:
Sk=SGk+ψq1SQlk+ψq2SQ2k+……+ψqnSQnk (3.0.6-2)
Where,
ψqi——the quasi-permanent value coefficient of the ith variable action Qi, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
3 In limit state of bearing capacity, the design value of the fundamental combination effect Sd controlled by variable action shall be determined according to the following formula:
Sd=γGSGk+γQlSQ1k+γQ2ψc2SQ2k+……+γQnψcnSQnk (3.0.6-3)
Where,
γG——the partial coefficient of permanent action, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009;
γQi——the partial coefficient of the ith variable action, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
4 For fundamental combination controlled by permanent action, simplification rule may also be adopted, and the design value of the fundamental combination effect Sd may be determined according to the following formula:
Sd=1.35Sk (3.0.6-4)
Where,
Sk——the design value of action effect of standard combination.
3.0.7 The design working life of foundation shall not be less than that of building structure.
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Basic Requirements
4 Geotechnical Classification and Index Properties
4.1 Geotechnical Classification
4.2 Engineering Index Properties
5 Foundation Design Calculation
5.1 Embedded Depth of Foundation
5.2 Bearing Capacity Calculation
5.3 Deformation Calculation
5.4 Stability Calculation
6 Foundation in Mountain Area
6.1 General Requirements
6.2 Foundation on Rock and Soil
6.3 Foundation on Compacted Fill
6.4 Landslide Prevention
6.5 Foundation on Rock
6.6 Karst and Sinkhole
6.7 Earth Slope and Gravity Retaining Wall
6.8 Rock Slope and Anchor Wall
7 Soft Ground
7.1 General Requirements
7.2 Usage and Treatment
7.3 Architectural Measurement
7.4 Structural Measurement
7.5 Massive Ground Surcharge
8 Foundation
8.1 Non-reinforced Spread Foundation
8.2 Spread Foundation
8.3 Strip Foundation under Columns
8.4 Raft Foundation of High-rise Buildings
8.5 Pile Foundation
8.6 Rock Bolt Foundation
9 Excavation Engineering
9.1 General Requirements
9.2 Excavation Engineering Exploration and Environmental Investigation
9.3 Earth Pressure and Water Pressure
9.4 Design Calculation
9.5 Internal Bracing of Support Structure
9.6 Soil Bolt
9.7 Excavation Engineering Inverse Practice
9.8 Excavation Engineering of Rock Mass
9.9 Underground Water Control
10 Inspection and Monitoring
10.1 General Requirements
10.2 Inspection
10.3 Monitoring
Appendix A Division of Rock Hardness and Rock Mass Integrity Degree
Appendix B Field Identification of Gravel Soil
Appendix C Key Points for Shallow Plate Load Testing
Appendix D Key Points for Deep Plate Load Testing
Appendix E Standardized Value for Shear Strength Parameters C and
Appendix F Contour of Seasonal Standardized Frost Depth in China
Appendix G Classification of Soil Expansion upon Freezing and Maximum Allowable Thickness of Frozen Earth above Building Foundation
Appendix H Key Points for Loading Test on Rock
Appendix J Requirements for Uni-axial Compressive Strength Testing on Rock
Appendix K Stress Influence Coefficient α and Average Stress Influence Coefficient
Appendix L Active Earth Pressure Coefficient ka for Retaining Wall
Appendix M Key Points for Pullout Resistance Testing on Rock Anchors
Appendix N Calculation of Subsequent Foundation Settlement under Massive Ground Surcharge
Appendix P Perimeter of Critical Section for Shearing and Polar Moment of Inertia Calculation
Appendix Q Key Points for Vertical Static Load Test on Single Pile
Appendix R Final Settlement Calculation for Pile Foundation
Appendix S Key Points for Lateral Load Test on Single Pile
Appendix T Key Points for Uplift Capacity Test on Single Pile
Appendix U Anti-shearing Sectional Width of Step and Cone-shape Pile Cap
Appendix V Stability Evaluation for Excavation Support Structures
Appendix W Anti-seepage Stability Evaluation for Foundation Pit
Appendix Y Key Points for Pre-stressed Earth Anchor Testing
Explanation of Wording in this Code
List of Quoted Standards
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.
According to the requirements of Document Jian Biao [2008] No. 102 issued by the Ministry of Housing and Urban-Rural Development-"Notice on Printing and Publishing the Development and Revision Plan of National Engineering Construction Standards in 2008 (first batch)", this code is revised from the former "Code for Design of Building Foundation" GB 50007-2002 by China Academy of Building Research jointly with all the organizations concerned.
During the preparation process, the drafting group finally finalized this code upon review based on extensive investigation and study, earnestly summarizing the practical experience, making reference to the foreign advanced standards, coordinating with relevant national standards and extensively soliciting for opinions.
This code comprises 10 chapters and 22 appendixes, with main technical content including general provisions, terms and symbols, basic requirements, geotechnical classification and index properties, foundation design calculation, foundation in mountain area, soft ground, foundation type, excavation engineering, inspection and monitoring.
The main technical contents revised in this code are:
1. Add the relevant content of excavation engineering in the design grade of foundation;
2. The design working life of foundation shall not be less than that of building structure;
3. Add the engineering definitions of peat and cumulosol;
4. Add resilience recompression deformation calculation method;
5. Add building anti-floating stability calculation method;
6. Add the design principles of soil-rock composite ground with rock face gradient greater than 10% and foundation soil thickness greater than 1.5m when the medium and underlying rock face is inclining in single direction;
7. Add the design content of rock foundation;
8. Add the principle of design of foundation for the site in karst region according to the karst development degree;
9. Add the calculation method for composite ground deformation;
10. Add the design requirements that the minimum ratio of reinforcement of spread foundation shall not be less than 0.15%;
11. Add the requirements for the shear bearing capacity calculation of oblique section when the short-side dimension of the spread foundation bottom is less than or equal to the column width plus 2 times the foundation effective height;
12. Adjust the settlement empirical coefficient through statistical analysis for pile foundation settlement calculation method;
13. Add the requirements that the excavation engineering featured by complex hydrogeologic conditions on site, high protection requirement for surrounding environment of foundation pit and Grade-A design grade shall be subjected to special design for underground water control in high underground water level area;
14. Add the engineering inspection requirements for ground treatment engineering;
15. Add the key points for horizontal loading test of single pile and key points for vertical pullout load testing of single pile.
In this code, the provisions printed in bold type are compulsory ones and must be enforced strictly.
The Ministry of Housing and Urban-Rural Development is in charge of the administration of this code and the explanation of the compulsory provisions; the China Academy of Building Research is responsible for the explanation of specific technical contents. During the process of implementing this code, the relevant opinions or advice, whenever necessary, can be posted or passed on to the national standard "Code for Design of Building Foundation" Administrative Group of China Academy of Building Research (address: No. 30, North Third Ring East Road, Beijing, 100013, China, Email: tyjcabr@sina.com.cn).
Chief development organization of this code: China Academy of Building Research
Participating development organizations of this code: CIGIS
Beijing Geotechnical Institute
China Southwest Geotechnical Investigation and Architecture Design Institute
Guiyang Architectural Design & Surveying Prospecting Co., Ltd.
Beijing Institute of Architectural Design
China Architecture Design and Research Group
Shanghai Xiandai Architectural Design Group Co., Ltd.
China Northeast Architectural Design & Research Institute
Liaoning Provincial Building Design & Research Institute
Yunnan Yicheng Architectural Design Company
Central-South Architectural Design Institute
Hubei Provincial Academy of Building Research
Guangzhou Academy of Building Research
Heilongjian Province Academy of Cold Area Building Research
Heilongjiang Province Building Engineering Quality Supervision Station
Northern Engineering & Technology Corporation, MCC
China State Construction Engineering Corp.
Tianjin University
Tongji University
Taiyuan University of Technology
Guangzhou University
Zhengzhou University
Southeast University
Chongqing University
Chief drafting staff of this code: Teng Yanjing, Huang Xiling, Wang Shuguang, Gong Jianfei, Wang Weidong, Wang Xiaonan, Wang Gongshan, Bai Xiaohong, Ren Qingying, Liu Songyu, Zhu Lei, Shen Xiaoke, Zhang Bingji, Zhang Chengjin, Zhang Jichao, Chen Xiangfu, Yang Min, Lin Liyan, Zheng Gang, Zhou Tonghe, Wei Wu, Hao Jiangnan, Hou Guangyu, Hu Daiwen, Yuan Neizhen, Gu Baohe, Tang Mengxiong, Gu Xiaolu, Liang Zhirong, Kang Jingwen, Pei Jie, Pan Kaiyun, Xue Huili
Chief examiners of this code: Xu Zhengzhong, Huang Shaoming, Wu Xuemin, Gu Guorong, Hua Jianxin, Wang Changqing, Xiao Ziqiang, Song Zhaohuang, Xu Tianping, Xu Zhangjian, Mei Quanting, Huang Zhihong, Dou Nanhua
Contents
1 General Provisions 1
2 Terms and Symbols 1
2.1 Terms 1
2.2 Symbols 2
3 Basic Requirements 3
4 Geotechnical Classification and Index Properties 8
4.1 Geotechnical Classification 8
4.2 Engineering Index Properties 11
5 Foundation Design Calculation 12
5.1 Embedded Depth of Foundation 12
5.2 Bearing Capacity Calculation 15
5.3 Deformation Calculation 19
5.4 Stability Calculation 24
6 Foundation in Mountain Area 26
6.1 General Requirements 26
6.2 Foundation on Rock and Soil 26
6.3 Foundation on Compacted Fill 28
6.4 Landslide Prevention 30
6.5 Foundation on Rock 32
6.6 Karst and Sinkhole 32
6.7 Earth Slope and Gravity Retaining Wall 35
6.8 Rock Slope and Anchor Wall 40
7 Soft Ground 42
7.1 General Requirements 42
7.2 Usage and Treatment 43
7.3 Architectural Measurement 45
7.4 Structural Measurement 46
7.5 Massive Ground Surcharge 47
8 Foundation 49
8.1 Non-reinforced Spread Foundation 49
8.2 Spread Foundation 50
8.3 Strip Foundation under Columns 60
8.4 Raft Foundation of High-rise Buildings 61
8.5 Pile Foundation 71
8.6 Rock Bolt Foundation 84
9 Excavation Engineering 85
9.1 General Requirements 85
9.2 Excavation Engineering Exploration and Environmental Investigation 87
9.3 Earth Pressure and Water Pressure 88
9.4 Design Calculation 89
9.5 Internal Bracing of Support Structure 90
9.6 Soil Bolt 91
9.7 Excavation Engineering Inverse Practice 92
9.8 Excavation Engineering of Rock Mass 94
9.9 Underground Water Control 94
10 Inspection and Monitoring 96
10.1 General Requirements 96
10.2 Inspection 96
10.3 Monitoring 99
Appendix A Division of Rock Hardness and Rock Mass Integrity Degree 101
Appendix B Field Identification of Gravel Soil 102
Appendix C Key Points for Shallow Plate Load Testing 103
Appendix D Key Points for Deep Plate Load Testing 104
Appendix E Standardized Value for Shear Strength Parameters C and 105
Appendix F Contour of Seasonal Standardized Frost Depth in China 107
Appendix G Classification of Soil Expansion upon Freezing and Maximum Allowable Thickness of Frozen Earth above Building Foundation 108
Appendix H Key Points for Loading Test on Rock 111
Appendix J Requirements for Uni-axial Compressive Strength Testing on Rock 113
Appendix K Stress Influence Coefficient α and Average Stress Influence Coefficient 114
Appendix L Active Earth Pressure Coefficient ka for Retaining Wall 128
Appendix M Key Points for Pullout Resistance Testing on Rock Anchors 134
Appendix N Calculation of Subsequent Foundation Settlement under Massive Ground Surcharge 135
Appendix P Perimeter of Critical Section for Shearing and Polar Moment of Inertia Calculation 137
Appendix Q Key Points for Vertical Static Load Test on Single Pile 140
Appendix R Final Settlement Calculation for Pile Foundation 142
Appendix S Key Points for Lateral Load Test on Single Pile 147
Appendix T Key Points for Uplift Capacity Test on Single Pile 151
Appendix U Anti-shearing Sectional Width of Step and Cone-shape Pile Cap 154
Appendix V Stability Evaluation for Excavation Support Structures 156
Appendix W Anti-seepage Stability Evaluation for Foundation Pit 160
Appendix Y Key Points for Pre-stressed Earth Anchor Testing 161
Explanation of Wording in this Code 163
List of Quoted Standards 164
1 General Provisions
1.0.1 This code is formulated with a view to implementing technical and economic policies of the nation in foundation design, and achieving safety and usability, advanced technology, economy and rationality, quality guarantee and environmental protection.
1.0.2 This code is applicable to the design of foundation of industrial and civil buildings (including structures). The design of collapsible loess, permafrost and expansive soil foundation and the foundation under the action of seismic and mechanical vibration load shall also meet the requirements of the current corresponding professional standard of the nation.
1.0.3 The design of foundation shall persist in the principle of adjusting measures to local conditions, using local materials, protecting environment and saving resources, comprehensively consider such factors as structure type, material condition and construction condition according to geotechnical engineering investigation data, and elaborately conduct.
1.0.4 The design of building foundation shall not only comply with this code, but also those in the current relevant ones of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 Ground, foundation soils
Soil mass or rock mass which supports foundation.
2.1.2 Foundation
Structure component which transfers various actions borne by the structure to the ground.
2.1.3 Characteristic value of subsoil bearing capacity
Pressure value corresponding to deformation specified within linear deformation section of subsoil pressure deformation curve determined by load test, and its maximum value is the proportion limit value.
2.1.4 Gravity density, unit weight
Gravity borne by rock-soil mass per unit volume, the product of density and gravity acceleration of rock-soil mass.
2.1.5 Rock discontinuity structural plane
Plane which cracks and is easy to crack in rock mass, such as bedding surface, joint, fault, schistosity, etc., also called discontinuous structural plane.
2.1.6 Standard frost penetration
Average value of maximum frost penetration actually measured for more than 10 years in the flat and exposed open area outside the city.
2.1.7 Allowable subsoil deformation
Deformation control value determined in order to guarantee normal use of the building.
2.1.8 Soil-rock composite ground
Ground with larger underlying bed rock surface gradient within the range of main bearing layer of building ground; or ground with densely-spread and exposed clint; or ground with exposed mass boulder or individual clint.
2.1.9 Ground treatment, ground improvement
Engineering measures to be taken in order to increase subsoil bearing capacity or improve its deformability or permeability.
2.1.10 Composite ground, composite foundation
Artificial ground that subsoil and reinforcement formed by reinforcing or replacing partial soil mass jointly bear load.
2.1.11 Spread foundation
Foundation that spreads a certain base area to side edge in order to diffuse the load transmitted from superstructure to make the compressive stress acted on the base meet the design requirements of subsoil bearing capacity and the internal stress of foundation meet the design requirements of material strength.
2.1.12 Non-reinforced spread foundation
Strip foundation under wall or independent foundation under column, composed of such materials as brick, rubble, concrete or rubble concrete, dirt and cement and not reinforced.
2.1.13 Pile foundation
Foundation which is composed of pile arranged in rock-soil and slab connected to pile top end.
2.1.14 Retaining structure
Structure which is built to make rock-soil side slope remain stable, control displacement and mainly bear lateral load.
2.1.15 Excavation engineering
General term of retaining structure, underground water control, environmental protection and other measures required for guaranteeing underground space formed in downward ground excavation safe and stable during the construction period of underground structure.
2.2 Symbols
2.2.1 Action and action effect
Ea——Active earth pressure;
Fk——Value of vertical force, transferred from superstructure to foundation top, corresponding to the acting standard combination;
Gk——Deadweight of foundation and soil weight on foundation;
Mk——Value of moment acts on the foundation bottom, corresponding to the acting standard combination;
pk——Average pressure at foundation bottom, corresponding to the acting standard combination;
p0——Average additional pressure at foundation bottom;
Qk——Vertical force borne by single pile in pile foundation under the action of axial vertical force, corresponding to the acting standard combination.
2.2.2 Resistance and material property
a——Compressibility coefficient;
c——Cohesion strength;
Es——Compression modulus of soil;
e——Void ratio;
fa——Corrected characteristic value of subsoil bearing capacity;
fak——Characteristic value of subsoil bearing capacity;
frk——Standardized value of uni-axial compressive strength of saturated rock;
qpa——Characteristic value of soil bearing capacity of pile tip;
qsa——Characteristic value of frictional force of pile periphery soil;
Ra——Characteristic value of vertical bearing capacity of single pile;
w——Moisture content of soil;
wL——Liquid limit;
wp——Plastic limit;
γ——Gravity density of soil, referred to as unit weight of soil;
δ——Friction angle between fill and retaining wall back;
δr——Friction angle between fill and resistant rock slope surface;
θ——Pressure diffusion angle of ground;
μ——Friction coefficient between soil and retaining wall base;
v——Poisson's ratio;
φ——Internal friction angle.
2.2.3 Geometric parameters
A——Foundation bottom area;
b——Foundation bottom width (minimum side length); or foundation bottom side length of moment action direction;
d——Embedded depth of foundation, pile body diameter;
h0——Foundation height;
Hf——Building height counting from foundation bottom;
Hg——Building height counting from outdoor ground;
L——Building length or unit length separated by settlement joint;
l——Length of foundation bottom;
s——Settlement volume;
u——Peripheral length;
z0——Standard frost penetration;
zn——Calculation depth of ground settlement;
β——Slope angle of side slope to horizontal plane.
2.2.4 Calculation coefficient
——Average additional stress coefficient;
ηb——Correction coefficient of bearing capacity of foundation width;
ηd——Correction coefficient of bearing capacity of embedded depth of foundation;
φs——Empirical coefficient of settlement calculation.
3 Basic Requirements
3.0.1 The design of foundation shall be divided into three design grades according to ground complexity, building scale and functional characteristics as well as the degree of building damage or normal use influence caused by possible ground problems, and shall be selected in accordance with those specified in Table 3.0.1 according to specific conditions.
Table 3.0.1 Design Grade of Foundation
Design grade Building and ground type
Grade A Important industrial and civil buildings
High-rise buildings with more than 30 storeys
Combined high- and low-storey building with complicated shape and storey number difference exceeding 10
Extensive multi-story underground building (such as underground garage, shopping mall and sports ground)
Building with specific requirements for subsoil deformation
Building on slope (including high slope) under complicated geological conditions
Newly-built building with larger influence on existing engineering
General building with complicated site and ground conditions
Excavation engineering of basement of two-storey or above building in complicated geological conditions and soft soil area
Excavation engineering with excavation depth greater than 15m
Excavation engineering with complicated surrounding environment condition and high environmental protection requirements
Grade B Industrial and civil buildings beyond Grade A and Grade C
Excavation engineering beyond Grade A and Grade C
Grade C Seven-storey or below civil buildings and general industrial buildings with simple site and ground conditions and even load distribution; secondary light buildings
Excavation engineering in non-soft soil area, with simple site geological conditions, simple foundation pit surrounding environment conditions, not high environmental protection requirements and excavation depth less than 5.0m
3.0.2 The design of foundation shall meet the following requirements according to the design grade of building foundation and the influence degree of subsoil deformation under the action of long-term load on superstructure:
1 The foundation design calculation of all the buildings shall meet the relevant requirements for calculation of bearing capacity;
2 The buildings with a design grade of Grade A or Grade B shall be designed according to subsoil deformation;
3 The buildings with a design grade of Grade C shall be subjected to deformation checking under one of the following conditions:
1) Buildings with characteristic value of subsoil bearing capacity less than 130kPa and with complicated shape;
2) When there is ground loading on the foundation and neighborhood or the difference between the adjacent loads is large, and the ground may be caused to generate excessive nonuniform settlement;
3) When the building on soft ground has eccentric load;
4) When the adjacent buildings are close and may have inclination;
5) When there is relatively thick or uneven fill in ground and the deadweight consolidation is not completed.
4 For high-rise buildings, high-rise structure, retaining wall, etc. frequently subjected to horizontal load, as well as buildings and structures built on slope or near side slope, their stability shall also be checked;
5 Excavation engineering shall be subjected to stability checking;
6 When building basement or underground structure has floating upward problem, anti-floating checking shall also be conducted.
3.0.3 The buildings with a design grade of Grade C within the range listed in Table 3.0.3 may not be subjected to deformation checking.
Table 3.0.3 Range of Buildings with a Design Grade of Grade C not Subjected to Subsoil Deformation Checking
Conditions of main bearing layer of ground Characteristic value of subsoil bearing capacity
fak(kPa) 80≤fak<100 100≤fak<130 130≤fak<160 160≤fak<200 200≤fak<300
Gradient of each soil layer (%) ≤5 ≤10 ≤10 ≤10 ≤10
Building type Masonry bearing structure and frame structure
(layer number) ≤5 ≤5 ≤6 ≤6 ≤7
Single-layer bent structure (6m column space) Single-span Rated lifting capacity of crane (t) 10~15 15~20 20~30 30~50 50~100
Plant building span
(m) ≤18 ≤24 ≤30 ≤30 ≤30
Multi-span Rated lifting capacity of crane (t) 5~10 10~15 15~20 20~30 30~75
Plant building span
(m) ≤18 ≤24 ≤30 ≤30 ≤30
Chimney Height (m) ≤40 ≤50 ≤75 ≤100
Water tower Height (m) ≤20 ≤30 ≤30 ≤30
Volume (m3) 50~100 100~200 200~300 300~500 500~1000
Notes: 1 The main bearing layer of ground refers to the range with a depth of 3b (b is the foundation bottom width) under strip foundation bottom, 1.5b under independent foundation, and thickness not less than 5m (except the general civil buildings less than two storeys);
2 If the main bearing layer of ground has soil layer with characteristic value of bearing capacity less than 130kPa, the design of masonry bearing structure in this table shall meet the relevant requirements of Chapter 7 of this code;
3 Masonry bearing structure and frame structure in this table refer to civil buildings; for industrial buildings, equivalent storey number of civil buildings may be converted according to plant building height and load condition;
4 The value of rated lifting capacity of crane, chimney height and water tower volume in this table refers to the maximum value.
3.0.4 Geotechnical engineering investigation shall be carried out before the design of foundation and shall meet the following requirements:
1 Geotechnical engineering investigation report shall be provided with the following data:
1) Check whether there is adverse geologic action influencing building site stability and assess the hazard degree;
2) Stratum structure and its uniformity within building range, physical and mechanical property indexes of each rock-soil layer as well as corrosiveness for building materials;
3) Underground water embedment condition, type, water-level fluctuation amplitude and rule, as well as corrosiveness for building materials;
4) Classify site category in seismic fortification zone, and carry out liquification evaluation for saturated sandy soil and silty soil;
5) Demonstrate and analyze the available design scheme of foundation, and propose economic and rational and advanced-technology design scheme suggestion; provide subsoil bearing capacity and deformation calculation parameters corresponding to the design requirements, and propose suggestion for problems to be noticed in design and construction;
6) If necessary for engineering, provide: rock-soil technical parameters required for slope stability calculation and support design of deep foundation pit excavation, demonstrate the influence on surrounding environment; technical parameters related to precipitation in foundation pit construction and suggestion for underground water control method; fortification water level for calculating underground water flotage.
2 The ground assessment should adopt boring sampling, laboratory soil test, penetration test and combine other in-situ test methods. For the buildings with a design grade of Grade A, load test index, shear strength index, deformation parameter index and penetration test data shall be provided; for the buildings of Grade B, shear strength index, deformation parameter index and penetration test data shall be provided; for the buildings of Grade C, penetration test and necessary boring and soil test data shall be provided.
3 All the building grounds shall be subjected to construction and foundation subsoil inspection. Where the ground condition doesn't conform to the original investigation report, construction investigation shall be carried out.
3.0.5 In design of foundation, the adopted action effect and corresponding resistance limit value shall meet the following requirements:
1 When determining foundation bottom area and buried depth according to subsoil bearing capacity or determining pile number according to single pile bearing capacity, the action effect transmitted to foundation or slab bottom shall be in accordance with the standard combination acting in limit state of normal use, and the corresponding resistance shall adopt characteristic value of subsoil bearing capacity or characteristic value of single pile bearing capacity;
2 When calculating subsoil deformation, the action effect transmitted to foundation bottom shall be in accordance with the quasi-permanent combination acting in limit state of normal use and shall not be counted into wind load and earthquake action; corresponding limit value shall be the allowable subsoil deformation;
3 When calculating retaining wall, ground or landslide stability and foundation anti-floating stability, the action effect shall be in accordance with the fundamental combination acting in limit state of bearing capacity, but the partial coefficient shall be 1.0;
4 When determining foundation or pile foundation slab height, retaining structure section, calculating internal force of foundation or retaining structure, determining reinforcement and checking material strength, the action effect transmitted from superstructure and corresponding base counterforce, retaining wall earth pressure and landslide thrust shall be in accordance with the fundamental combination acting in limit state of bearing capacity, and the corresponding partial coefficient shall be adopted; if it is necessary to check the foundation crack width, they shall be in accordance with the standard combination acting in limit state of normal use;
5 Foundation design safety class, structure design service life and significance coefficient of structure shall be adopted according to the relevant specifications, but the significance coefficient of structure Υ0 shall not be less than 1.0.
3.0.6 In the design of foundation, the design value of the action combination effect shall meet the following requirements:
1 In limit state of normal use, the design value of the standard combination effect Sk shall be determined according to the following formula:
Sk=SGk+SQ1k+ψc2SQ2k+……+ψcnSQnk (3.0.6-1)
Where,
SGk——the effect of standardized value of permanent action Gk;
SQik——the effect of standardized value of the ith variable action Qik;
ψci——the combination value coefficient of the ith variable action Qi, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
2 The design value of the quasi-permanent combination effect Sk shall be determined according to the following formula:
Sk=SGk+ψq1SQlk+ψq2SQ2k+……+ψqnSQnk (3.0.6-2)
Where,
ψqi——the quasi-permanent value coefficient of the ith variable action Qi, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
3 In limit state of bearing capacity, the design value of the fundamental combination effect Sd controlled by variable action shall be determined according to the following formula:
Sd=γGSGk+γQlSQ1k+γQ2ψc2SQ2k+……+γQnψcnSQnk (3.0.6-3)
Where,
γG——the partial coefficient of permanent action, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009;
γQi——the partial coefficient of the ith variable action, valued according to the requirements of the current national standard "Load Code for the Design of Building Structures" GB 50009.
4 For fundamental combination controlled by permanent action, simplification rule may also be adopted, and the design value of the fundamental combination effect Sd may be determined according to the following formula:
Sd=1.35Sk (3.0.6-4)
Where,
Sk——the design value of action effect of standard combination.
3.0.7 The design working life of foundation shall not be less than that of building structure.
Contents of GB 50007-2011
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Basic Requirements
4 Geotechnical Classification and Index Properties
4.1 Geotechnical Classification
4.2 Engineering Index Properties
5 Foundation Design Calculation
5.1 Embedded Depth of Foundation
5.2 Bearing Capacity Calculation
5.3 Deformation Calculation
5.4 Stability Calculation
6 Foundation in Mountain Area
6.1 General Requirements
6.2 Foundation on Rock and Soil
6.3 Foundation on Compacted Fill
6.4 Landslide Prevention
6.5 Foundation on Rock
6.6 Karst and Sinkhole
6.7 Earth Slope and Gravity Retaining Wall
6.8 Rock Slope and Anchor Wall
7 Soft Ground
7.1 General Requirements
7.2 Usage and Treatment
7.3 Architectural Measurement
7.4 Structural Measurement
7.5 Massive Ground Surcharge
8 Foundation
8.1 Non-reinforced Spread Foundation
8.2 Spread Foundation
8.3 Strip Foundation under Columns
8.4 Raft Foundation of High-rise Buildings
8.5 Pile Foundation
8.6 Rock Bolt Foundation
9 Excavation Engineering
9.1 General Requirements
9.2 Excavation Engineering Exploration and Environmental Investigation
9.3 Earth Pressure and Water Pressure
9.4 Design Calculation
9.5 Internal Bracing of Support Structure
9.6 Soil Bolt
9.7 Excavation Engineering Inverse Practice
9.8 Excavation Engineering of Rock Mass
9.9 Underground Water Control
10 Inspection and Monitoring
10.1 General Requirements
10.2 Inspection
10.3 Monitoring
Appendix A Division of Rock Hardness and Rock Mass Integrity Degree
Appendix B Field Identification of Gravel Soil
Appendix C Key Points for Shallow Plate Load Testing
Appendix D Key Points for Deep Plate Load Testing
Appendix E Standardized Value for Shear Strength Parameters C and
Appendix F Contour of Seasonal Standardized Frost Depth in China
Appendix G Classification of Soil Expansion upon Freezing and Maximum Allowable Thickness of Frozen Earth above Building Foundation
Appendix H Key Points for Loading Test on Rock
Appendix J Requirements for Uni-axial Compressive Strength Testing on Rock
Appendix K Stress Influence Coefficient α and Average Stress Influence Coefficient
Appendix L Active Earth Pressure Coefficient ka for Retaining Wall
Appendix M Key Points for Pullout Resistance Testing on Rock Anchors
Appendix N Calculation of Subsequent Foundation Settlement under Massive Ground Surcharge
Appendix P Perimeter of Critical Section for Shearing and Polar Moment of Inertia Calculation
Appendix Q Key Points for Vertical Static Load Test on Single Pile
Appendix R Final Settlement Calculation for Pile Foundation
Appendix S Key Points for Lateral Load Test on Single Pile
Appendix T Key Points for Uplift Capacity Test on Single Pile
Appendix U Anti-shearing Sectional Width of Step and Cone-shape Pile Cap
Appendix V Stability Evaluation for Excavation Support Structures
Appendix W Anti-seepage Stability Evaluation for Foundation Pit
Appendix Y Key Points for Pre-stressed Earth Anchor Testing
Explanation of Wording in this Code
List of Quoted Standards
