During the recent years, the use of pozzolanic materials (e.g. volcanic ash) in concrete and cement manufacturing has increased significantly since it can reduce the environment hazard associated with using Portland cement. In this paper, the effect of elevated temperatures on the physical and mechanical characteristics of building mortar produced with volcanic ash is experimentally explored. In order to evaluate the performance of the mortar, four different proportions of volcanic ash (0, 5, 15 and 25%)-as weight replacement of the cement-were prepared. A series of tests were conducted after 28, 90 and 120 days under different temperatures (25, 200, 500 and 800Cº). This paper demonstrates that the replacement of cement by a proportion of volcanic ash can sustain an acceptable level of compressive strength and improve the overall characterization of the mortar while reducing the amount of CO2 released. The mortar with 15% ratio of the volcanic ash replacement showed better flexural and the tensile strength. This paper also heights that the volcanic ash replacement affects the late-age properties of the mortar more than the early-age ones at both ambient and elevated temperatures.

Due to increasing cost of asphalt binder, significant economic savings can be realized by using the amount from reclaimed asphalt pavement (RAP) in the production of new hot mix asphalt (HMA). Moreover, this is an environmentally friendly option as it reduces the demand for virgin materials. It has to be remarked that in Iraq RAP is not used in the production of HMA and this valuable material is mostly degraded for use in lower value applications. Four mixtures were designed, which contains three different percent RAP, it is (0%, 5%, 15%) with asphalt grade (40-50) and (25%) with asphalt grade (60-70), it has been changed the grade of asphalt when adding RAP (25%) to compensate for the aged binder in the RAP when adding to mixture. All types of tests result demonstrated that all mixtures have good properties compared with the virgin mixture. This demonstrated that mixtures with RAP content could be successfully designed to meet the local volumetric and performance-specification requirements.

The important component in the asphalt mixture is mineral filler materials as it plays an essential part in the stiffening and toughening of asphalt binder. In addition, the mechanical properties of asphalt binder are influenced by the mineral filler, and significantly affected with respect to stripping or moisture susceptibility. This paper is displayed the mechanical properties of asphalt mixtures that used asphalt binder grade (40-50), the gradation of aggregates selected with the mid-point according to the Iraqi specification and two types of mineral filler materials (High Reactivity Attapulgite (HRA) and Portland Cement (PC)) according to the empirical requirements. The mixtures are produced and compacted according to the Marshall Mix design method. In addition, this paper is displayed the positive influence of HRA and PC in the asphalt mixtures such as (Volumetric Properties, Marshall Properties, Marshall Stiffness, the Indirect Tensile Strength and Moisture Susceptibility). The results explained that the (5%) and (7%) HRA had an important influence on the properties of asphalt mixtures. With the increment in the percentages of HRA, the volumetric properties of asphalt mixtures enhanced. Laboratory investigation results support the advantage of adding HRA to the asphalt mixtures. HRA as an active mineral filler has good resistance to moisture sensitivity and mechanical properties, which contributes to extending the life cycle of the pavement layer.

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