×
The submission system is temporarily under maintenance. Please send your manuscripts to
Go to Editorial ManagerThe effect of fines content (material finer than 0.075 mm) on the mechanical properties of subbase course aggregate is studied in this paper. a laboratory tests were carried out using percentage of fines material 5%, 10% and 15% by weight adding to the original subbase aggregate class B according to Iraqi specification (SCRB) which the specification limit the range of fines between 5-15%. The repeated load CBR test was done to study the mechanical properties; accumulative permanent, elastic deformation and equivalent elastic modulus.The RL CBR test was useful technique to assess the influence of fines material and stress level on the equivalent elastic modulus, and on the evolution of deformation. The equivalent modulus increase when adding 5% of fines material in case of plastic fines, but in case of non-plastic the increase continues until adding 10% fines material. Adding fines material also led to change in accumulative permanent deformation, where adding 5% fines material increase the permanent deformation by 36%, 5% for material with plastic fines and 20% for material with non-plastic fines for unsoaked samples. In case of soaked samples permanent deformation increase by 28% and 25% at adding fines material for material with plastic fines where decrease by 1% at adding 5% fines to original granular material with non-plastic fines. The theoretical modeling show that the deformation increase by increasing number of loads repetitions.
Soil reinforcement techniques have been successfully used to improve the shear properties of weak soils in recent years. To improve the utilization of waste resources and promote sustainable development of infrastructure amid rapid urbanization, one potential option for reinforcement materials is human hair fibers (HHF). Because it is a natural fiber, there are risks to human and environmental health associated with the improper disposal of human hair fiber, an occurring waste product that does not decompose completely. This fabric is abundant, has a high reusability rate, and is ideal for use as a reinforcement to address waste management issues and make the most of inefficient or unnecessary manufacturing websites for long-term sustainability. The CBR test was executed on several samples with diverse fiber possibilities to evaluate the engineering properties of the randomly placed HHF in clayey soil samples using fibers whose average length was 50 mm and whose diameter ranged from 60 to 80 microns and compared the outcomes to those of unreinforced soil. The soil sample was treated with different percentages of Human Hair fiber (0%, 0.75%, 1.5%, 1.75% and 2.25%). The results showed that the value of CBR of the soil sample decrease at 0.75% of HHF and then increased up to 2.25% of HHF.