Narrow Results

The groundwater in the subgrade always fluctuates under the influence of the atmosphere (rainfall, drainage, the fluctuation of river), especially in unsaturated soil. Thus, it is necessary to study the drainage effect of different drainage materials in unsaturated soil subgrade. This paper studies the drainage hydraulic calculation method of underground sewers, as well as its drainage effect in unsaturated soil subgrade. It shows that an underground sewer in the subgrade is necessary. The numerical calculation method of sewer drainage can be used to analyze the groundwater seepage in subgrade soils. The sewer can discharge the groundwater in sprinklers effectively. The other methods should be implemented to ensure the subgrade is in steady moisture, and the drainage ability is strong when the sewer is deep and it can be enhanced by increasing the number of sewers and reducing the space of the sewers.

Ribbed plate construction is a shallow foundation system known to provide stiff planar substructure capable of transferring large vertical loads more uniformly to the subgrade. One special class of ribbed mat foundations has been patented in Indonesia and is called the spider net construction (Konstruksi Pondasi Sarang Laba-Laba/KSLL). KSLL can function as pavement or foundation system and consists of rib, plate and infill materials. This study, first discusses the importance of different components in ribbed mat foundation and then develops the design strategy to apply it for airport and highway pavements. The effectiveness of ribbed mat foundation in comparison with the conventional rigid pavement construction is also elaborated.