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Over the past few years, some studies have introduced the capability of using avideo camera and a videogrammetric technique in capturing the spatial changes inmoving bodies. However, the previous studies have not evaluated the accuracy oftracking objects moving at different speeds. Thus, this research discusses of thefeasibility of using a digital camera and a videogrammetric technique to capturespatial changes of objects moving at different speeds. The study includes validatingthe accuracy of a digital camera on videoing and tracking moving objects anddetermining effects of speed variations on the accuracy of monitoring moving objects.A car (Mark KIA, SOUL) having many target points was chosen in this study torepresent a moving object. The car was videoed at four circumstances (static andmoving at speed (5km/h), (10 km/h) and (15km/h)) by two cameras mounted in twodifferent angles to get stereo video clips. By utilizing videogrammetric technique, thestereo clips were used to determine the coordinates of target points placed on the carin the four circumstances. The accuracy of the work was evaluated by comparing the3D coordinates of the targets determined using videogrammetry with the values ofthese points (control points) measured by total station. The assessment show that adigital camera are appropriate to achieve accurate and reliable measurement reachto millimeters when tracking a moving object at low speed (5km/h, 10km/h and15km/h) and the videogrammetric technique can determine the spatial location ofpoints on a dynamic object with total accuracy between (RMSE= 2.00 mm to 4.00mm)).

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Cement is among the important contributors to carbon dioxide emissions in modern society. Researchers are studying solutions to reduce the cement content in concrete to minimize the negative impact on the environment. Among these solutions is replacing cement with other materials, such as waste, which also poses environmental damage and requires landfill areas for disposal. Among these wastes are eggshell powder ash (ESPA) and wheat straw ash (WSA), which were utilized as cement substitutes in green mortar production. Thirteen mixtures were cast, one as a reference without replacement and twelve others that included replacing ESPA and WSA (single and combined) with cement in 2%, 4%, 6%, and 8% proportions of cement's weight. The mechanical (compressive and flexural strength), microstructural (SEM), and thermogravimetric analysis (TG/DTA) properties of all mixtures were examined. The results showed a remarkable improvement in mechanical properties, and the best improvement was recorded for the (4%ESPA+4%WSA) mixture, which reached 73.3% in compressive strength and 56% in flexural strength, superior to the reference mixture. Furthermore, SEM analyses showed a dense and compact microstructure for the ESPA and WSA-based mortars. Therefore, the WSA and ESPA wastes can be recycled and utilized as a substitute for cement to produce an eco-friendly binder that significantly improves the microstructural and mechanical characteristics of mortar. In addition, combining the two materials also presents a viable option for creating a sustainable ternary blended binder (with cement) that boasts superior properties compared to using the WSA or ESPA individually.