Detail of JTG/T B02-01-2008

Introduction of JTG/T B02-01-2008

1.0.1 This guideline was established with a view to implementing "Law of the People's Republic of China on Protecting Against and Mitigating Earthquake Disasters", adopting the policy of prevention first, alleviating the earthquake damages on highway bridges, protecting people's life and property safety, decreasing economic losses and better exerting the functions of the highway traffic network and its actions in the seismic relief. 1.0.2 This guideline is mainly applicable to concrete beam bridges, masonry or concrete arch bridges whose single span is no more than 150m. As for the cable stayed bridges, suspension bridges and oversize span beam bridges and arch bridges whose single span exceeds 150m, they may be designed referring to the seismic design criteria given in this guideline. 1.0.3 According to the significance of highway bridges and difficulty of restoration (emergency repair) in this guideline, the seismic fortifications for bridges are classified into four classes, namely, class A, class B, class C and class D, respectively corresponding to different seismic fortification criterions and fortification targets. 1.0.4 As for highway bridges in areas where the seismic fortification intensity is magnitude 6 and above, seismic design must be carried out for them. 1.0.5 This guideline is applicable to the seismic design of highway bridges in areas where the seismic fortification intensity is magnitude 6, 7, 8 and 9. As for bridges in areas where the seismic fortification intensity is larger than magnitude 9 and large-span or special bridges with special requirements, their seismic design shall be studied specially and conducted according to the relevant specific requirements. 1.0.6 The seismic fortification intensity must be determined according to those documents (drawings) approved and issued by the national due authorities. As a rule, the seismic fortification intensity may be adopted in accordance with the basic seismic intensity specified in the current "Seismic Ground Motion Parameter Zonation Map of China". As for those bridges whose sites have already been conducted with special seismic safety evaluation, their seismic fortification shall be carried out according to the approved seismic fortification intensity or design seismic ground motion parameters. 1.0.7 As for the seismic design of highway bridges, except for the requirements in this guideline, those in the relevant national and professional standards and codes also shall be complied with.

Contents of JTG/T B02-01-2008

1 General Provisions - 1 - 2 Terms and Symbols - 2 - 2.1 Terms - 2 - 2.2 Symbols - 3 - 3 Basic Requirements - 6 - 3.1 Seismic fortification targets, classifications and criteria of bridges - 6 - 3.2 Basic requirements for determining the earthquake action - 7 - 3.3 Flow figure of seismic design - 7 - 3.4 Action effect combination - 8 - 4 Site and Foundation - 9 - 4.1 Site - 9 - 4.2 Bearing capacity of the foundation - 10 - 4.3 Foundation liquefaction and soft soil foundation - 11 - 5 Earthquake Action - 15 - 5.1 General rules - 15 - 5.2 Design acceleration response spectrum - 15 - 5.3 Design ground motion time history - 17 - 5.4 Design ground motion power spectrum - 17 - 5.5 Seismic active earth pressure and hydrodynamic pressure - 17 - 6 Seismic Analysis - 20 - 6.1 General rules - 20 - 6.2 Ductility seismic design of beam bridges - 23 - 6.3 Modeling criteria - 24 - 6.4 Response spectral method - 25 - 6.5 Time history analysis method - 26 - 6.6 Power spectrum method - 26 - 6.7 Calculation for regular bridges - 26 - 6.8 Calculation of capacity protected members - 30 - 6.9 Abutment - 31 - 7. Checking Calculation of Strength and Deformation - 33 - 7.1 General requirements - 33 - 7.2 The checking calculation of Type D bridge-girder, masonry arch bridge, gravity type bridge pier and abutment. - 33 - 7.3 The checking calculation of aseismic strength of bridge of Type B and C - 34 - 7.4 The deformation checking calculation of pier column of bridge-girder of type B and C - 35 - 7.5 The bearing checking calculation of bridge-girder of Type B and C - 37 - 8 Ductility Design of Structural Details - 39 - 8.1 Structure measures of pier columns - 39 - 8.2 Structure measures of nodes - 40 - 9 Seismic Design of Special Bridges - 43 - 9.1 General rules - 43 - 9.2 Seismic concept design - 43 - 9.3 Modeling and analytical principles - 43 - 9.4 Performance requirements and seismic checking - 44 - 9.5 Seismic measures - 44 - 10 Seismic Isolation Design of Bridges - 45 - 10.1 General rules - 45 - 10.2 Isolated equipments - 45 - 10.3 Modeling criterion and analysis methods for isolated bridges - 45 - 10.4 Performance requirement and seismic checking - 46 - 11 Seismic Measures - 47 - 11.1 General rules - 47 - 11.2 Area with magnitude 6 - 47 - 11.3 Area with magnitude 7 - 48 - 11.4 Area with magnitude 8 - 49 - 11.5 Area with magnitude 9 - 50 - Appendix A Approximate Formula of Fundamental Period of Bridge Structure - 51 - A.1 Approximate formula of fundamental period of beam bridge's pier - 51 - A.2 Fundamental period proximate calculation formulae of the beam bridge which adopts rubber bearing of plate type - 52 - Appendix B Yield Curvature and Ultimate Curvature Calculation of Round and Rectangular Section - 54 - Appendix C Implementation Principles of Power Spectrum Method - 56 - C.1 Calculation of auto-power spectrum responded by the structure when the ground is in uniform motion - 56 - C.2 Calculation of auto-power spectrum responded by the structural when the traveling wave effect in considered. - 56 - C.3 Calculation of structural response demand - 56 - Appendix D Computing Formula of Seism Earth Pressure of Cohesive Backfill - 58 - Wording Explanations - 60 -