Fabric formwork can be used in both cast-in-place and precast applications. It offers several advantages over conventional formwork technology and provides opportunities for innovations in architectural and structural concrete members. arabic 10 English 48
Hakim Salem Abdelgader Abdelgader (3-2018)

Concrete is a material that is widely used in the construction market due to its availability and cost, although it is prone to fracture formation. Therefore, there has been a surge in interest in self-healing materials, particularly self-healing capabilities in green and sustainable concrete materials, with a focus on different techniques offered by dozens of researchers worldwide in the last two decades. However, it is difficult to choose the most effective approach because each research institute employs its own test techniques to assess healing efficiency. Self-healing concrete (SHC) has the capacity to heal and lowers the requirement to locate and repair internal damage (e.g., cracks) without the need for external intervention. This limits reinforcement corrosion and concrete deterioration, as well as lowering costs and increasing durability. Given the merits of SHCs, this article presents a thorough review on the subject, considering the strategies, influential factors, mechanisms, and efficiency of self-healing. This literature review also provides critical synopses on the properties, performance, and evaluation of the self-healing efficiency of SHC composites. In addition, we review trends of development in research toward a broad understanding of the potential application of SHC as a superior concrete candidate and a turning point for developing sustainable and durable concrete composites for modern construction today. Further, it can be imagined that SHC will enable builders to construct buildings without fear of damage or extensive maintenance. Based on this comprehensive review, it is evident that SHC is a truly interdisciplinary hotspot research topic integrating chemistry, microbiology, civil engineering, material science, etc. Furthermore, limitations and future prospects of SHC, as well as the hotspot research topics for future investigations, are also successfully highlighted.
Hakim S. Abdelgader (4-2022)

Abstract Pouring of concrete underwater is necessary in the implementation of most in-shore, and off-shore structures. The pouring of underwater concrete is considered as a challenge for engineers, even during the design stage or during implementation and supervision. This is due to the fact that many precautions must be taken for the success of casting process. The most important precaution is to protect the fresh concrete during the casting process from the water to avoid the risk of washout of cement past and segregation of aggregates. Concrete can be placed underwater successfully though good design of concrete mix, and through choosing the most suitable method for placing of concrete. There are new techniques for underwater concreting such as grouted aggregate which is known as two-stage concrete (TSC) method which, as the name implies, consists of filling a form work with the coarse aggregate and then injecting the grout to fill the voids through pumping tubes extended to the bottom of the form. The main objective of the thesis is to present the capability of pouring the concrete underwater by using (TSC) method. A laboratory model was prepared and visually investigated and tested by extracting core samples, performing compressive test, tensile test and using ultrasonic pulse velocity test. From the obtained results it has been observed that, it is possible to pour concrete underwater by using two stage concrete in successful way, and it is recommended to develop this research by using different water cement ratios and cement sand ratios to get the optimum mix design and also, different types of aggregates which are available in local quarries.
منال فاروق النجار (2010)