1.0.1 The Guidelines is formulated with a view to improving the construction technique level of highway roadbases and subbase and ensuring the construction quality.
1.0.2 The Guidelines are applicable to base and subbase construction in newly constructed, extended and renovated projects of all-class highways.
1.0.3 Raw materials, construction mix ratio, construction process as well as quality standard and control provisions meeting the Guidelines shall be adopted; economical and reasonable local materials with reliable technology shall be preferred under the premise of satisfying the technical requirements of practical engineering.
1.0.4 The quality assurance system shall run through the whole construction process to define the quality responsibilities of full staff, enhance the quality control and management of each process and ensure the engineering quality.
1.0.5 A sound safety production management system and emergency plan shall be established to define the safety accountability and strictly enforce safe operation rules, and ensure the occupational health of construction personnel and construction safety.
1.0.6 Focus on optimal land utilization, reduction of energy and material consumptions and environmental protection.
1.0.7 Economical and reasonable new technology, new material, new equipment and new process shall be positively and reliably adopted.
1.0.8 In addition to the requirements stipulated in the Guidelines, Highway roadbases and subbase construction shall comply with those stipulated in the current relevant national and professional standards
2 Terms
2.0.1
base
main bearing stratum directly below surface course of asphalt pavement, or structural layer directly below the cement concrete panel
2.0.2
subbase
secondary bearing stratum paved under asphalt pavement base or auxiliary layer paved under cement concrete pavement base
2.0.3
cement stabilized material
mixture taking cement as binder and formed through mixing with to-be-stabilized material by adding water, including cement stabilized graded crushed stone, cement stabilized graded gravel, cement stabilized stone chips, cement stabilized soil, cement stabilized sand, etc.
2.0.4
composite stabilized material
mixture taking two or more kinds of materials as binder and formed through mixing with to-be-stabilized material by adding water, including cement and lime stabilized material, cement fly ash stabilized material, lime and fly ash stabilized material, etc.
2.0.5
lime stabilized material
mixture taking lime as binder and formed through mixing with to-be-stabilized material by adding water, including lime crushed stone soil, lime soil, etc.
2.0.6
industrial waste stabilized material
mixture taking lime or cement as binder and industrial wastes like coal slag, steel slag, mineral waste residue as main to-be-stabilized material and formed through mixing by adding water
2.0.7
graded crushed stone
mixture with crushed stones and stone chips (of various particle sizes) mixed according to certain proportion, gradation satisfying certain requirements and plasticity index and bearing ratio meeting specified requirements
2.0.8
graded gravel
mixture with gravel and sand (of various particle sizes) mixed according to certain proportion, gradation satisfying certain requirements and plasticity index and bearing ratio meeting specified requirements
2.0.9
crushed stone
crushed stone mixture obtained by removing oversize particles from crushed stones of different particle sizes with sieve whose mesh size complies with the maximum particle size specified for the engineering
2.0.10
coefficient of loose paving material
ratio of thickness of loose paving material to compaction thickness reaching the specified compactness
2.0.11
permitted delay time
maximum permitted time interval after cement stabilized material mixing and before rolling formation under the premise of satisfying the strength standard
2.0.12
compaction time
number of rolling compaction calculated on the basis that road roller compacting by rolling along the same or close wheelmark back and forth for once respectively is called as 1 time of rolling compaction
3 Raw Material Requirements
3.1 General
3.1.1 During raw material test assessment, sufficient samples shall be randomly selected for material test.
3.1.2 Recycled material whose technical index is ought to meet the relevant requirements of the Guidelines may be used for the construction of highway with the structure layer and road grade lower than those of the original road.
