Highway Bridge and Culvert Design General Specifications JTG D60—2004

Author: Edited by China Road and Bridge Research Institute
Publisher:
Publishing Time: Not available
Features: This revision of the specification incorporates the developments and requirements of China's highway bridges over the past decade, making comprehensive improvements to the original specification. The main revisions include:
1. Clarified that highway bridge and culvert structures should be designed for both ultimate limit states and serviceability limit states, introducing three design conditions for structural design: permanent, temporary, and accidental conditions.
2. Modified the combination methods and coefficients of action effects for highway bridge and culvert structural design, introducing short-term and long-term effect combinations of actions, and proposing frequent value coefficients for short-term effect combinations and quasi-permanent value coefficients for long-term effect combinations.
3. Introduced the safety level and importance coefficient for highway bridge and culvert design, using different importance coefficients based on the severity of potential consequences of structural failure, making the design more rational.
4. Conducted a special study on "Classification Standards for Highway Bridges and Culverts," adjusting the classification standards based on the research findings.
5. Conducted a special study on "Flood Frequency Standards for Highway and First-Grade Highway Bridge and Culvert Design," analyzing and comparing the original standards with relevant domestic and international standards, as well as evaluating design flood calculation methods. Through comprehensive analysis, it was concluded that the original specification's provisions could be maintained.
6. Replaced the original vehicle load classification with the Highway-I and Highway-II standard vehicle load standards, removing the verification loads for trailers and tracked vehicles, and indirectly reflecting the impact of verification loads in vehicle loads.
7. Changed the calculation method for the vehicle impact coefficient, now primarily based on the structural fundamental frequency instead of span length.
8. Partially adjusted the standard values for pedestrian load.
9. Adjusted the calculation formulas for loads and their influencing coefficients, providing a national basic wind speed map and a table of basic wind and wind pressure values for meteorological stations across the country.
10. Added calculation methods and formulas for ice pressure.
11. Improved the provisions for temperature effects, refined the system temperature specifications, and adjusted the temperature gradient curve specifications.
12. Added calculations and design requirements for vehicle impact loads.
13. Added provisions for the impact of seagoing vessel collisions.