Studies on Effect of Wheel Configuration-Temperature and Type of Binder on Rutting Characteristics of Bituminous Concrete Mix
This report presents the investigation of rutting characteristics of bitumen mixes using plain bitumen (VG-10) and modified binders (CRMB-60 and PMB-70). The report will be of particular interest to engineers in the public and private sectors with responsibility for the design, construction, maintenance and rehabilitation of HMA pavements. The present work is aimed at understanding the properties of mix and the machine parameters which influence the deformation causing ruts for mixes. The rutting was caused on the beam specimens prepared in the laboratory. The study includes the influence of different types of binders, air voids, and along with the applied loads on the rutting characteristics. The results are analyzed to formulate regression equations. It is found that modified binders resist rutting compared to plain binders. PMB-70 binders perform better than VG-10 and CRMB-60 binders under the laboratory induced applied pressures and number of passes.
Performance Studies of Gap-Graded Mixes using Elastomer Modifier for Wearing Course
:- Road construction crossing the world created huge demand for construction materials. Natural aggregates is the prime material for the road construction use of aggregates leads to question about the preservation of natural resource. In other hand use of recycled pavement asphalt (RAP) as a alternative material in place natural aggregate which makes environmental friendly construction material. This research investigated the feasibility of using reclaimed asphalt pavement in stone mastic asphalt mix by modifying the binder with waste engine oil and elastomer modifier. RAP is replaced with aggregates at 10%, 20%, 30% & 40%. Further in order to increase the percentage of RAP in SMA mix waste engine oil and elastomer modifier is added i.e., RAP of 50%, 60% and 70%. The results indicated that 30% of RAP is found to be feasible through laboratory investigation for SMA mixes and 60% RAP is found to be feasible to use in SMA mix through laboratory investigation by modifying binder with waste engine oil and elastomer modifier.
Formation and Strength of Magnesia Whiskers
The formation of single-crystal magnesia whiskers during the compressive deformation of single crystals at room temperatures is described. These whiskers can have strengths of the order of millions of pounds per square inch. They are formed during fracture as a result of the discontinuous propagation of cracks which are mechanically relieving internal stresses resulting from plastic flow