The difference between highway asphalt pavement design code 2017 and 2006

JTG D50-2017 "Code for Design of Highway Asphalt Pavement".

The main differences compared with the original JTG D50-2006 are:

1.The traffic load classification has been adjusted, and the extremely heavy traffic level has been added; Cumulative equivalents are used.

The application of the traffic load grade of axle load action is inconvenient, and it is more appropriate to divide the traffic volume of trucks, and the new specification divides the traffic load grade by the cumulative traffic volume of the pavement design period;

2.Cancel the underlayment.

The asphalt pavement structure layer can be made from top to bottom by the surface layer. Grass roots. The subbase layer and the necessary functional layer are composed. The functional layer includes antifreeze layer, drainage layer, isolation layer, particle layer, permeable layer, etc.;

3.Modulus of rebound on the top surface of the road bed.

The requirements have been greatly improved from the original specification, which is about 2 or 3 times that of the original specification. The rebound modulus of the original standard roadbed was pressed into the bearing plate experiment. The new specification is determined by triaxial experimental test of the rebound modulus of the roadbed. The original specification uses the humidity of the roadbed in the most unfavorable season, and this code adopts the humidity of the roadbed when it is balanced;

4.The classification indexes and standards of subgrade humidity were adjusted, and the temperature adjustment coefficient and equivalent temperature were introduced.

5.The original specification used consistency to characterize the dry and wet state of the roadbed, but the consistency could not reflect the humidity state of the non-cohesive soil and accurately reflect the influence on the resilience modulus. In addition, moisture content.

At the same time, the change causes the change of soil compactness, which is also a major factor affecting the resilience modulus. And the saturation of the soil.

It reflects the influence of moisture content and compactness. Saturation is therefore used instead;

6.Adopt a damage-specific design index system. The design indexes of permanent deformation of subgrade, permanent deformation of asphalt layer and low-temperature cracking of pavement are added, the fatigue cracking prediction model of asphalt layer and inorganic binder layer is improved, and the surface deflection value is cancelled.

Index; 7.The design parameters of pavement materials and subgrade were changed, the test methods were adjusted, and three levels of pavement materials and subgrade design parameters were stipulated.

8.The investigation and analysis methods of axle load spectrum and traffic parameters were standardized.

9.The chapter arrangement was sorted out, the design requirements of the structural combination were highlighted, and the terms and symbols were standardized.

Highway asphalt pavement design code.

jtg d50-2017

Announcement No. 10 of the Ministry of Transport of the People's Republic of China.

Announcement of the Ministry of Transport on the issuance of the "Highway Asphalt Pavement Design Code".

The Code for the Design of Highway Asphalt Pavement (JTG D50-2017) is now issued, as the industry standard for highway engineering, which will come into force on September 1, 2017, and the original Code for the Design of Highway Asphalt Pavement (JTG D50-2006) shall be repealed at the same time.

Highway asphalt pavement design code (JTG D50-2017) was compiled by Zhongjiao Road and Bridge Technology. The management and interpretation of the standard belongs to the Ministry of Transport, and the daily management and interpretation work is responsible for the technical work of CCCC Road and Bridge.

Please pay attention to the relevant units in practice to sum up experience, and timely inform the problems found and modification suggestions to Zhongjiao Road and Bridge Technology **** (address: Jiangsu Building, No. 88, Andingmenwai Street, Dongcheng District, Beijing, postal code: 100011), so that it can be used when revising.

The announcement is hereby made. Ministry of Transport of the People's Republic of China.

March 10, 2017.

The allowable deviation of asphalt pavement thickness is less than 5% of the total thickness.

The pavement thickness requires the allowable deviation of the total thickness to be -5%mm, and the allowable deviation of the upper layer is -10%mm. The thickness deviation of the asphalt concrete pavement of the first-class highway shall not be less than -5%mm of the total thickness, and the upper layer shall not be less than -10%mm.

This is clearly stipulated in the quality inspection and evaluation standards of highway engineering. Usually after the asphalt concrete pavement is completed, the core sample is taken out on site, measured with a ruler or vernier caliper, the total thickness is taken out first, and then the thickness of the upper layer is measured again, both of which are within the specified range, it is regarded as qualified.

Crack advantages of asphalt pavement:

1. Sufficient mechanical properties to withstand various forces exerted on the road surface by vehicle loads.

2. It has elastic and plastic deformation ability, and can withstand strain without damage.

3. The adhesion with the car tires is good, which can ensure the safety of driving.

4. It has a high degree of shock absorption, which can make the car run quickly, smoothly and with low noise.

5. It is not easy to raise dust in summer, and it is very beneficial to clean up. <>

According to the "Highway Asphalt Pavement Design Code JTGD50-2006", the structural depth of high-speed and first-class highway TD is not less than and not greater than.

According to the provisions of the "Highway Asphalt Pavement Design Code JTGD50-2006" and the "Technical Guide for Asphalt Pavement Surface Penetration and Regeneration Repair", the structural depth of asphalt pavement is not less than.

According to the provisions in the specification, the structural depth of cement concrete pavement has the following provisions: the depth of high-speed and first-class highway construction is not less than and not greater than; The depth of other highway structures is not less than and not greater than.

In order to meet the needs of highway construction and development, make asphalt pavement meet the use requirements, ensure pavement quality, improve engineering durability, and formulate asphalt concrete pavement design specifications.

Legal basis: Article 29 of the Road Traffic Safety Law of the People's Republic of China The planning, design and construction of roads, parking lots and road supporting facilities shall meet the requirements of road traffic safety and smoothness, and be adjusted in a timely manner according to traffic demand. If the traffic management department of the public security organ finds that there are frequent traffic accidents on the road that has been put into use, or there are serious traffic safety hazards in parking lots and road supporting facilities, it shall report to the local people in a timely manner, and put forward suggestions to prevent traffic accidents and eliminate hidden dangers, and the local people shall make a decision in a timely manner.

Legal analysis: In order to meet the needs of highway construction and development, make asphalt pavement meet the use requirements, ensure the quality of pavement, and improve the durability of the project, the design specifications for asphalt concrete pavement are formulated.

Legal basis: Article 29 of the Road Traffic Safety Law of the People's Republic of China The planning, design and construction of roads, parking lots and road supporting facilities shall meet the requirements of road traffic safety and smoothness, and be adjusted in a timely manner according to traffic demand. The traffic management department of the public security organ finds that there are frequent traffic accidents on the road that has been put into use, or the parking lot and road supporting facilities are in the heart of the serious traffic safety hazard of Tsai Xiaoye, should be reported to the local people in a timely manner, and put forward suggestions to prevent traffic accidents and eliminate the hidden dangers of caution, and the local people should make a decision in a timely manner.