Analysis of the Effects of Applying Different Quantities and Types of Additives on Strength Parameters of Cold in-Situ Recycled Mixtures Made of Bitumen Foam

Nowadays recycling technology is used in many branches of science e.g. road civil works. In this research, 162 specimens of mixtures were produced by Reclaimed Asphalt Pavement (RAP) made from cut old pavements. The Cold in-situ recycling (CIR) method with foam bitumen was applied. It is mentioned that each specimen has a weight of approximately 1200 g. The final goal of this article is to represent an experimental study on tensile strength, resilience module, the ability to tolerate the dry and saturate indirect tensile stress (ITSDry and ITSSat) and the tensile stress ratio (TSR) of these mixtures. For this purpose, 162 Marshal Samples were built and cured for the time period of 72 hours under temperature of 40, and then, these specimens were analyzed and tested with UTM14, to obtain their module of resilience, in the laboratory of Ministry of Road and Transportation. Moreover, the total number of the samples (162) was divided into 3 equal groups and Marshal Strength, ITSDry and ITSSat tests were performed for each group, including 54 specimens. The differences between the samples were the amounts of bitumen foam (%1,%2, & %3), percentage and type of additives or active fillers which include %0, %1 and %2 of every type of active filler, such as Portland cement type II, slaked lime, quick lime, oven slag, pozzolan, and rubber powder. The Granulation of the RAP and the temperature of bitumen were assumed to be constant. To finalize the issue, the results of the above- mentioned tests showed that through applying SPSS and MATLAB software and artificial neutral networks modeling, one can forecast these results. Also, with a sufficient accuracy, the effect of each additive with its specific percentage of foam bitumen on the strength parameters would be measurable.