Manufacturing of fiber-reinforced concrete bridge arches

Objective. A new method of manufacturing arches for a fiber-reinforced concrete bridge in the form of an analogue of permanent formwork is considered. Within the framework of this work, research results have been obtained that confirm the effectiveness of the system for the construction of bridge arches of various configurations.Method. The proposed developments will improve the strength characteristics of the bridge arch for small and medium bridges by optimizing the shape and size of the cross section in accordance with the change in the bending moment along the length of the arch. At the same time, reduce its metal consumption by several times.Result. The results obtained confirmed the effectiveness of electrostatic spraying of dry concrete mixture with simultaneous moisture up to moisture, which contributes to the work of capillary forces for compaction of concrete layers and the manufacture of a profiled strong shell (analogue of non-removable reinforced formwork) from reinforced fiber-reinforced concrete.Conclusion. By varying the shape and dimensions of the cross- section, the thickness of the shell and the degree of its reinforcement, as well as filling this shell with high-strength fiber-reinforced concrete, it is possible to design and manufacture bridge arches for various loads.

Reinforcement of metal structures by external reinforcement by gluing high-strength fiber-reinforced systems: analytical approach

Ukraine's construction heritage includes numerous examples of the use of metal structures, especially those used in industrial buildings and high-span structures. The use of metal structures in construction is due primarily to their mechanical properties. They are frost-resistant and can withstand temperatures down to -65 degrees, hard, durable, strong and reliable. They can also be used in areas with high seismic activity. But, as in the case of other types of structures, there is a need to restore or strengthen metal structures due to structural defects, wear of load-bearing elements, as well as to increase the load-bearing capacity. In some cases, reinforcement with fiber-reinforced polymer composites (FRP) gives a better result compared to traditional methods of reinforcement using metal

Critical Analysis of the Selection of Non-Conventional Machining Processes

Non-Convectional Machining (NCM) processes are used widely to produce accurate and intricate material shape such as titanium, stainless steels and resistant alloy that are of high strength, fiber-based composite, refractories and ceramics. The production of more complex shapes of materials using convectional machining processes is considered to be challenging. This research paper focusses on the section of the most effective NCM process. The ‘choice’ of the most considerable NCM process for a particular application could be seen as a multi-technique for making proper choices for diverse or conflicting approaches. To aid the process of choosing, various NCM techniques have been proposed in this research. This contribution focuses on the usage of unexplored NCM and Multi-Feature Decision-Making (MFDM) ‘choice’ issues.