Loading...
Search for:
aggregates
0.07 seconds
Evaluation of Aggregate Angularity Using Image Analysis
, M.Sc. Thesis Sharif University of Technology ; Tabatabaee, Nader (Supervisor)
Abstract
Form and angularity of aggregates are two important shape characteristics that have a significant effect on the performance of hot-mix asphalt. The first step toward the study of the effect of these characteristics on pavement performance is their proper measurement. Current test methods used in practice have several limitations in measuring these characteristics. In this thesis, a method based on image processing called “Sharif Aggregate Imaging System (SHAMS)” has been introduced which is capable of directly measuring aggregate dimensions and determining angularity index for aggregates classification. Calculated results related to the form and angularity of aggregates measured by SHAMS...
Numerical Modeling of Non-Cemented and Cemented Ballast Aggregates under Triaxial Test with a Flexible Membrane Using Discrete Element Method (DEM)
, M.Sc. Thesis Sharif University of Technology ; Pak, Ali (Supervisor)
Abstract
This research deals with numerical simulation of triaxial test to determine behavior of non-cemented and cemented ballast aggregates used in base and subbase of roads and railroads. Ballast aggregates, thanks to their high strength and durability, are widely used in various fields including dam, river, road construction, and railway. One of the most widespread uses of this material is in the road body, and according to the recommendation of the British Highway Center, the materials used in the road body are well-graded gravel with the maximum size of 20 mm. Cement is also used as a corrective material to enhance the performance of road bodies. Therefore, knowing the characteristics of these...
Discrete Element Method (DEM)Modeling of the Behavior of Uncemented and Cemented Coarse-Grained Soils in Triaxial Test Using Non-Spherical Particles
, M.Sc. Thesis Sharif University of Technology ; Pak, Ali (Supervisor)
Abstract
The present research focuses on the numerical modeling of the behavior of uncemented and 1% and 2% cemented coarse-grained materials commonly used in the base and subbase of roads and railways. Portland cement is used as a stabilizing material to improve the performance of aggregates in road/railroad construction, which requires an understanding of the mechanical properties of these materials for optimal design. Numerous triaxial tests under monotonic and cyclic loading have been conducted to investigate the mechanical properties of these materials. Conducted laboratory experiments have several limitations, such as high costs, membrane rupture under high confining pressures, and the...