Detail of JTG 3370.1-2018

Introduction of JTG 3370.1-2018

1General Provisions 1.0.1These Specifications are intended to provide standards and guidelnes for design of highway tunnels. 1.0.2These Specifications are applicable to all classes of new, reconstructed or expandedhighway tunnels excavated primarily by drill-and-blast method. 1.0.3Tunnel designs shall fulfill highway functions and follow the basic principles of " safety . durability,economy and environmentai protection" . 1.0.4 Highway tunnels can be grouped into four categories by length, as specified in Table 1. 0. 4. 1.0.8Tunnel design shall be such that land use is minimal, existing vegetation preserved whereverpossible and muck and sewage properly disposed. 1.0.9Tunnel design shall proactively and safely adopt new technologies , materials, equipmentand processes in line with relevant national technological and economic policies. 1.0. 10Highway tunnel design shall comply with relevant current national and industrial standards,in addition to these Specifications herein. 2Terms and Symbols 2.1 Terms 2.1.1 Highway tunnel An underground passageway for motor vehicles, non-motor vehicles and pedestrians to passthrough. Highway tunnels are commonly classified into motor vehicle tunnels and mixed-usetunnels for motor vehicles, non-motor vehicles and pedestrians 2.1.2 Mountain tunnel A tunnel featured by excavation through mountains 2.1.3 Drill-and-blast tunnel A tunnel excavated bymanually or mechanically drilling boreholes, loading explosives and controlled blasting 2.1.4Cui-and-cover tunnel A tunnel byilt by cut and cover method 2.1.8 Emergency stop zone An area inside the tunnel for temporary parking of faulty or inspection vehicles 2.1.9Cross passage A transverse, nearly horizontal passage linking two tunnels or caverns, or linking the tunnel toground surface 2.1.10 Vertical shaft A vertical excavation provided to improve operational ventilation or construction conditions 2.1.11 Inclined shaft An inclined excavation at a certain angle to improve operational ventilation or construction conditions 2.1.12 Twin tunnels with small clearanceI'wo parallel tunnels constructed in sufficiently close proximity to each other such that one will havea structural impact on the other. 2.1.20 Distortional pressure The pressure acting on the lining structure as a result of deformation of surrounding rock mass 2.1.21 Rock load The pressure acting on the lining structure as a result of deformation or loosening of surroundingrock mass, It is a collective term for distortional pressure and loosening pressure 2.1.22 Eccentric load Unsymmetrical load acting on a tunnel’s lining structure 3Tunnel Survey and Surrounding RockClassification 3.1General 3. 1.1 The content and scope of survey data to be collected shall be established according to theobjectives at each phase of the tunnel design.Scoping surveys shall also consider the highwayclass, tunnel requirements and size before carrying out data collection, survey, mappingexploration and test. The survey datashal be complete andaccurate to provide sufficientinformation to fulfil the design requirements. 3.6.5 The physical and mechanical parameters of each class of surrounding rock should beobtained from laboratory or field tests. If there are no test data and preliminary classification, theycan be selected from Table A.0.7-1 in Appendix A hereto. The shear peak strength of rock massdiscontinuity may be selected from Table A.0.7-2 in Appendix A hereto. If measurement data areunavailable , physical and mechanical parameters of each class of surrounding soil may be obtainedfrom Table A.0.7-3 in Appendix A hereto.

Contents of JTG 3370.1-2018

1General Provisions 2 Terms and Symbols 2.1 Terms 2.2 Symbols 3 Tunnel Survey and Surrounding Rock Classification3.2 Collection of available informatión3.3 Topographical and geological survey 3.1Genera 3.4 Meteorological survey 3.5 Survey of engineering environment 3.6 Surrounding rock classifieation 4Overall Design 4.1Ceneral 4.2Tuanel siting 4.3Tunnel alignment designClear section design 4.5Cross passage and parallel adit 4.7Construction plan 5 Building Materials 5.1 General 5.2 Material properties 5.3Properties of waterproof and drainage materials 6 Load 6.1 General 6.2 Permanent load6.3 Variable loads 6.4 Accidental loads7 Portal & Portal 7.1 General 7.2 0pening engineering7.3 Portal engineering8 Design of Lining Structure 8.1 General 8.2 Shotcrete and rockbolt lining 9 Structural Calculation 9.1General 9.2 Lining caleulation Calculation for cut-and-covef tunnelCalcúlation for portalsWaterproofing and Drainage 10General 10.2Waterproofing 10.3Drainage 10.5Waterproofing and drainage for tunnels in cold regions 11 Special Types of Tunnels 11.1 General 11.2 Twin tunnels with small clearance 11.3 Twin-arch tunnel 11.4 Branching-out tunnel 12 Auxiliary Channel 12.1General 12.2 Vertical shaft 12.3 Inclined shaft 12.4 Parallel adit and cross passage 12.5 Duct and underground machine room 12.6 Intersection 13 Auxiliary Engineering Measures 13.1 General 14 Design of Tunnels in Special Geology 14.1 General 14.2 Swelling surrounding rock 15 Tunnel Subgrade and Pavement 15.1 General 15.2 Tunnel subgrade 15.3 Tunnel pavement 16 Seismic Design 16.1 Seismic fortification classification and standard 16.2 Earthquake effect 16.3Seismic design check 16.4Seismic measures 16.5 In-tunnel facilities 17 Reconstruction and Expansion Design 17.1General 17.2 Tunnel reconstruction and expansion scheme design 17.3 Tunnel expansion 17.4 Tunnel reconstruction 17.5 Additional tunnel 18 In-tunnel Reservation,Embedment and Structures