Kazakhstan has revised one of the key standards in the road industry, ST RK 1218-2003, which regulates testing methods for asphalt concrete and organo-mineral mixes.

The new edition, developed by the Kazakhstan Road Research Institute (KazdorNII), takes into account modern climatic, technological, and load changes, and is synchronized with international and Eurasian requirements.

The main innovation is the introduction of a new method for determining the compaction coefficient. When calculating the compaction coefficient, it is now permissible to take into account the secondary crushing of gravel that occurs during compaction. For this purpose, data from both reformed samples, reflecting changes in the structure of the material under load, and samples molded from the original mix are used, depending on the purpose of the test. This is particularly relevant for sections with heavy traffic and unstable weather conditions.

“The change in the method for calculating the compaction coefficient allows for more accurate control and longer service life of the structural layers of the road pavement,” explained KazdorNII.

In recent years, Kazakhstan's road infrastructure has faced a number of new challenges, such as climate change and increasing temperature ranges, increased transport and axle loads, the introduction of new materials and technologies in construction, and the need to harmonize with TR TS 014/2011 and EAEU standards.

All these factors require a more accurate and scientifically sound approach to road materials testing. The updated ST RK 1218-2003 meets these requirements.

The following points have also been changed:

• A method for comprehensive assessment of the adhesive properties of asphalt concrete, taking into account high and low temperature effects, has been introduced;
• The temperature conditions for preparing mixes have been updated in accordance with ST RK 1225 and ST RK 1223;
• The marking of viscous bitumens has been brought into line with GOST 33133 and ST RK 1373;
• The rules for the selection and processing of samples, including the number and order of core combination, have been clarified;
• The accuracy of density calculations has been improved and technical inaccuracies in the wording have been eliminated;
• Square-mesh sieves have been added in accordance with the technical regulations of the Customs Union.

The update of the standard creates a basis for improving the quality and reliability of road pavements, improving laboratory control at all stages of construction, and effectively transitioning to international engineering practices.

ST RK 1218-2003 is used in the design and control of mixes used for the pavement of motorways, airfields, city streets, squares and landscaped areas. The introduction of new methods will ensure a higher level of safety and sustainability of Kazakhstan's roads.