This research aims to introduce a new technique—off-site and self-form segmental concrete masonry arches fabrication, without the need of construction formwork or centering. The innovative construction method in the current study encompasses two construction materials forms the self-form masonry arches, wedge-shape plain concrete voussoirs, and carbon fiber-reinforced polymer (CFRP) composites. The employment of CFRP fabrics was for two main reasons: bonding the voussoirs and forming the masonry arches. In addition, CFRP proved to be efficient for strengthening the extrados of the arch rings under service loadings. An experimental test was conducted on four sophisticated masonry arch specimens. The research parameters were the Keystone thickness and the strengthening of the self-form arch ring at the intrados. The major test finding was that the use of thicker Keystone alters the behavior of the self-form arch and considerably increases the load carrying capacity by 79%. Partial strengthening of the intrados with CFRP fabrics of typical arch ring Keystone resulted considerable increase in the debonding load of fabrication CFRP sheets by 81%, increase in the localized crushing load by 13% and considerably increase voussoir sliding load by 107%.

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Two of the main advantages of segmental construction are economics, as well as the rapid construction technique. One of the forms of segmental construction, for structural elements, is the segmental beams that built-in short sections, which referred to segments. This research aims to exhibit a new technique for the fabrication of short-span segmental beams from wedge-shaped concrete segments and carbon fiber reinforced polymers (CFRP) in laminate form. The experimental campaign included eight short-span segmental beams. In this study, two selected parameters were considered. These parameters are; the number of layers of CFRP laminates and the adhesive material that used to bond segments to each other, forming short-span segmental beams. The test results showed that for segmental beams reinforced by 2-layer of CFRP laminates, undergoes less deflection and sustained considerable ultimate loading value of 38.4%–104% than beams reinforced by 1-layer. Moreover, the test of segmental beams fabricated by adhering to the concrete segments with epoxy resin exhibited an increase in ultimate loading by 16%–65% than beams constructed using cementitious adhesive for bonding the wedge-shaped segments. Theoretically, segmental beams were analyzed by the American Concrete Institute (ACI) 440.2R-17 procedure with slight modifications. The analysis gave an overestimation of flexural strength for segmental beams when compared with experimental outcomes.

Recently, Iraq has experienced an unprecedented seismic activity, specifically, near the east boundary with Iran which reveals the need to re-evaluate the seismic hazard at this region. This study consists of two phases. The first is collecting the earthquake records covering the recent events till the end of November 2017 including the 12 November 2017 (7.3Mw) earthquake, and applying data processing to get the net data for independent events for the study area which were more than 4300 of net main earthquakes of Mw ≥ 4 and were used in the second phase. The second phase is applying the PSHA method by dividing the study area into a grid of small cells of size 0.5 0.5°and the hazard parameters were calculated at the center of each of these grid cells then, converting the final results to contours over the study area. It is found that the values increases towards the east-northeast and north due to the continued tectonic boundary convergence between the Arabian, Iranian and Turkish plates which produces intense earthquake activity. The design spectral acceleration at 0.2 and 1.0 seconds found to be 0.33, 0.17, 0.47, 0.25, 0.71, 0.35 g for Basra, Baghdad and Erbil, respectively. The comparison between the PGA values from this study and from the seismic hazards maps from Iraqi seismic codes of 1989, 1997 and 2016, for return periods of 475 and 2475 years, reveals the continued increase with time which reveals the need to updating the seismic hazard maps continuously.