1.0.1 This specification was formulated with a view to unifying the technical standards for design of highway subgrade and making the design of highway subgrade engineering meeting the requirements on safety and reliability, advanced technology and economic feasibility.
1.0.2 This specification is applicable to the subgrade design of the constructed, reconstructed and extended highways of various classes.
1.0.3 Subgrade shall have sufficient strength, stability and durability.
1.0.4 As for subgrade design, the engineering geological investigation and test work along the highway shall be well done to ascertain the hydrological conditions and geological conditions along the line and to obtain the physical and mechanical parameters of rock and soil necessary for design.
1.0.5 Subgrade design shall reasonably determine the subgrade scheme and form integrated design via comprehensive technical and economic comparison and selection according to the function and class of highway and in compliance with the principles of adaptation to local conditions, use of local materials, land conservation and environment protection.
1.0.6 Subgrade design shall follow the relevant technical and economic policies of the Nation, and actively adopt new techniques, structures, materials and processes with caution.
1.0.7 In addition to the requirements stipulated in this specification, the subgrade design shall also comply with those specified in the current relevant national and professional standards.
1 General Provisions
2 Terminologies and Symbols
2.1 Terminologies
2.2 Symbols
3 General Subgrade
3.1 General Requirements
3.2 Roadbed
3.3 Filling Subgrade
3.4 Excavated Subgrade
3.5 Treatment of the Junction between Filling and Excavation of Subgrade
3.6 High Embankment and Steep Slope Embankment
3.7 Deep Cutting
3.8 Rockfill Embankment
3.9 Lightweight Embankment
3.10 Industrial Waste Embankment
3.11 Soil Borrow and Spoil for Subgrade
4 Subgrade Drainage
4.1 General Requirements
4.2 Surface Drainage
4.3 Underground Drainage
5 Subgrade Protection and Retaining
5.1 General Requirements
5.2 Slope Protection
5.3 Protection of Riverside Subgrade
5.4 Retaining Wall
5.5 Side Slope Anchorage
5.6 Soil Nailing Support
5.7 Slide-resistant Pile
6 Subgrade Widening and Rebuilding
6.1 General Requirements
6.2 Survey Evaluation of Existing Subgrade Condition
6.3 The Subgrade Widening and Rebuilding of Class II and Below Highways
6.4 Subgrade Widening and Rebuilding of Expressway and Class I Highway
7 Special Subgrade
7.1 General Requirements
7.2 Subgrade in Landslide Section
7.3 Subgrade in Collapse Section
7.4 Subgrade in Talus Section
7.5 Subgrade in Debris Flow Section
7.6 Subgrade in the Karst Area
7.7 Subgrade in Soft Soil Area
7.8 Subgrade in Red Clay and High Liquid Limit Soil Areas
7.9 Subgrade in Expansive Soil Area
7.10 Subgrade in Loess Area
7.11 Subgrade in Saline Soil Area
7.12 Subgrade in Permafrost Area
7.13 Subgrade in Sand Storm Area
7.14 Subgrade in Snow Damage Section
7.15 Subgrade in Salivary Flow Ice Section
7.16 Subgrade in mined-out area
7.17 Coast Subgrade
7.18 Subgrade in Reservoir Section
7.19 Subgrade in Seasonally Frozen Soil Area
Appendix A Standard Test Method for Dynamic Resilience Modulus of Subgrade Soil
Appendix B Value Range of Dynamic Resilience Modulus of Subgrade Soil
Appendix C The Method for Pre-estimating the Equilibrium Moisture of Subgrade
Appendix D Range of Moisture Adjustment Coefficient for Resilience Modulus of Subgrade
Appendix E Rock Mass Classification for Rock Slope
Appendix F Monitoring Contents and Items of Subgrade
Appendix G Strength Requirements for Materials of Drainage, Protection and Retaining Structures
Appendix H Design and Calculation of Retaining Wall
Appendix J Loess Zoning Map
Appendix K Classification of Permafrost Highway Engineering
Explanation of Wording in this Specification
1.0.1 This specification was formulated with a view to unifying the technical standards for design of highway subgrade and making the design of highway subgrade engineering meeting the requirements on safety and reliability, advanced technology and economic feasibility.
1.0.2 This specification is applicable to the subgrade design of the constructed, reconstructed and extended highways of various classes.
1.0.3 Subgrade shall have sufficient strength, stability and durability.
1.0.4 As for subgrade design, the engineering geological investigation and test work along the highway shall be well done to ascertain the hydrological conditions and geological conditions along the line and to obtain the physical and mechanical parameters of rock and soil necessary for design.
1.0.5 Subgrade design shall reasonably determine the subgrade scheme and form integrated design via comprehensive technical and economic comparison and selection according to the function and class of highway and in compliance with the principles of adaptation to local conditions, use of local materials, land conservation and environment protection.
1.0.6 Subgrade design shall follow the relevant technical and economic policies of the Nation, and actively adopt new techniques, structures, materials and processes with caution.
1.0.7 In addition to the requirements stipulated in this specification, the subgrade design shall also comply with those specified in the current relevant national and professional standards.
Contents of JTG D30-2015
1 General Provisions
2 Terminologies and Symbols
2.1 Terminologies
2.2 Symbols
3 General Subgrade
3.1 General Requirements
3.2 Roadbed
3.3 Filling Subgrade
3.4 Excavated Subgrade
3.5 Treatment of the Junction between Filling and Excavation of Subgrade
3.6 High Embankment and Steep Slope Embankment
3.7 Deep Cutting
3.8 Rockfill Embankment
3.9 Lightweight Embankment
3.10 Industrial Waste Embankment
3.11 Soil Borrow and Spoil for Subgrade
4 Subgrade Drainage
4.1 General Requirements
4.2 Surface Drainage
4.3 Underground Drainage
5 Subgrade Protection and Retaining
5.1 General Requirements
5.2 Slope Protection
5.3 Protection of Riverside Subgrade
5.4 Retaining Wall
5.5 Side Slope Anchorage
5.6 Soil Nailing Support
5.7 Slide-resistant Pile
6 Subgrade Widening and Rebuilding
6.1 General Requirements
6.2 Survey Evaluation of Existing Subgrade Condition
6.3 The Subgrade Widening and Rebuilding of Class II and Below Highways
6.4 Subgrade Widening and Rebuilding of Expressway and Class I Highway
7 Special Subgrade
7.1 General Requirements
7.2 Subgrade in Landslide Section
7.3 Subgrade in Collapse Section
7.4 Subgrade in Talus Section
7.5 Subgrade in Debris Flow Section
7.6 Subgrade in the Karst Area
7.7 Subgrade in Soft Soil Area
7.8 Subgrade in Red Clay and High Liquid Limit Soil Areas
7.9 Subgrade in Expansive Soil Area
7.10 Subgrade in Loess Area
7.11 Subgrade in Saline Soil Area
7.12 Subgrade in Permafrost Area
7.13 Subgrade in Sand Storm Area
7.14 Subgrade in Snow Damage Section
7.15 Subgrade in Salivary Flow Ice Section
7.16 Subgrade in mined-out area
7.17 Coast Subgrade
7.18 Subgrade in Reservoir Section
7.19 Subgrade in Seasonally Frozen Soil Area
Appendix A Standard Test Method for Dynamic Resilience Modulus of Subgrade Soil
Appendix B Value Range of Dynamic Resilience Modulus of Subgrade Soil
Appendix C The Method for Pre-estimating the Equilibrium Moisture of Subgrade
Appendix D Range of Moisture Adjustment Coefficient for Resilience Modulus of Subgrade
Appendix E Rock Mass Classification for Rock Slope
Appendix F Monitoring Contents and Items of Subgrade
Appendix G Strength Requirements for Materials of Drainage, Protection and Retaining Structures
Appendix H Design and Calculation of Retaining Wall
Appendix J Loess Zoning Map
Appendix K Classification of Permafrost Highway Engineering
Explanation of Wording in this Specification
