Roads Foundation & Construction
Road projects have become one of the important projects in our present community just like many other vital projects. Road systems include various types of roads whose names vary according to their importance, capacity, performance and the purpose for which they were established. Various types of roads range from high-speed and large-sized to local streets in areas that carry traffic low traffic . According to the Saudi road system , this can be summarized in three main sections, namely:
Main Roads: Roads that connect the main cities of the Kingdom. They are identified by two numbers.
Secondary roads: Roads that connect the medium-important cities and then connect them with the main road network. They are identified by three numbers.
Sub-roads: Roads that connect villages, deserts, farms, and other roads. They are identified by four numbers.
In addition to these three types, there are precise definitions of other types of roads, such as highway, main road, service road and agricultural roads . In general, it is possible to identify any type of road from the name given to it.
Road construction stages
After completing the planning and design process selecting the optimum road path and width , the type of pavement , completing the technical inspection and the schedule of quantities , preparing the feasibility studies that refer that the project is feasible economically , then the items of the technical inspection are to be implemented as follow :
First Stage
Surveying works , drawing contour lines and hidden arms, and drawing a construction line showing the soil layers and space and the successful bituminous base layer in laboratory tests.
Second Stage
After performing the surveys and preparing the plans , we do the settlement and modification of the natural land based on the construction line that shows the areas of excavation and burial areas until the soil is settled according to the levels taken in the previous item and according to the construction line .
Third Stage
Successful layers of dirt were added and settled by laboratory tests according to the construction line and levels in the form of layers not more than 15 cm thick and then sprayed with water in an appropriate amount for the purpose of obtaining the best water content and then tamped with staple or rubber mashers according to the type of soil to obtain a maximum dry density and a percentage not less than 95% according to the modified Proctor method .
Fourth Stage
Successful substrate or space layers are added with laboratory tests, leveled and amalgamated exactly as in the above item .
Fifth Stage
The surface of the space is sprayed with Prime Coat (1 asphalt: 1.5 gasoline or kerosene) and wait until the ground is impregnated with the substance .
Sixth Stage
Successful pavement layers are spread through laboratory tests by spreaders and conveying mechanisms and are free at the bedding (110 degrees) with a thickness of not less than 10 cm and flattened by tube rollers that spray water during compaction so that the asphalt concrete material does not become attached to it, and then with rubber rollers until it hardens and the percentage of compaction is not less than 97%
