# Evaluation of Resilient Modulus and Rutting for Warm Asphalt Mixtures: A Local Study in Iraq
## 1 Introduction
NCAT conducted in situ investigations in numerous states between 2006 and 2010 in collaboration with each state's DOT. They have discovered generally encouraging results in their performance assessment of WMA combinations. The NCHRP project 09-43 was carried out to offer suggestions for mixed design methods for WMA [18]. The main outcome of the research effort was that a standalone WMA mix design technique was not required. According to the NCHRP 09-43, the project's investigation of the content of the binder, HMA and WMA mixtures made with similar aggregates and binders did not have significantly different average design binder contents [19]. [PERSON] et al. [20] estimated the compatibility and workability of WMA mixes. A comparison of the Superpave Gyratory Compactor and Marshall compactor's compaction rates revealed that mixes with greater levels of WMA additions compacted more readily than a control mixture without WMA additives when the mixture temperature was reduced to below (110-115) \({}^{\circ}\)C.  
Mixing temperatures which has lower value could cause more water to get trapped in the aggregate Due to concerns about an increase in moisture-induced damage, this raises a red flag, questioning how well these blends perform in the field. These problems are exacerbated by WMA techniques that add chemicals or foam to mixtures to boost moisture content. Additionally, lower mixing temperatures will cause the mixes to become less oxidatively hardened, although this diminished hardening may increase the mixes' resistance to rutting [17]. In the case of WMA with zeolites, [PERSON] [21] stated that the findings of the chemical and physical tests are consistent the stiffness of the mix, its resistance to water, and its resistance to rutting. These measurements unquestionably depend on the materials being utilized (the asphalt, aggregate type, and zeolite), in addition to the testing procedure and parameters, at least in part. Alumino-silicates of alkali metals make up the synthetic zeolite which is known as Aspha-min. About twenty percent of the product comprises water that is released when the temperature rises. Zeolite can absorb and lose water without damaging its crystal structure. It is usually used by a percentage of weight-based of 0.3 percent by the total mix weight. Synthetic zeolite releases a low amount of water when the temperature is high, approximately between (100-200) \({}^{\circ}\)C, which causes a little asphalt binder volume increase which leads to a depression in the value of viscosity [22]. The rutting distress can be defined as the distortion of the surface of the asphalt pavement due to the applied load [23]. Reduced temperature results in less oxidative binder hardening, which could result in more rutting and less stability in hot weather [24]. Despite this fact, the earlier lab tests and the observations in the field show that the mixes of WMA have rutting performance comparable to the mixes of HMA [25]. [PERSON] [21] stated that multi-factor variance research revealed that the inclusion of zeolite has no impact on the modulus of stiffness and wheel-tracking of mixed asphalt. The findings of the HMA samples compacted at 149 \({}^{\circ}\)C were compared, and it was discovered that the resistance o rutting had increased and WMA with zeolite compacted at 129 \({}^{\circ}\)C in conjunction with PG 58-28 alone and limestone aggregate. The stiffness modulus value was related to the type of asphalt being used. The type of aggregate and asphalt employed, as well as the compaction temperature, to a lesser extent, determined the resistance to rutting [25]. The asphalt binder aging tends to be reduced as a result of the WMA mixture's low compaction temperature. The density improvement of the compacted mixtures may somewhat counterbalance this drop, which could tend to increase the possibility of rutting [26]. [PERSON] and [PERSON] [25; 27] evaluated the WMA using the Asphalt Pavement Analyzer (APA) test and showed the applicability of using zeolite and synthetic wax in different processes.