Papers by Keyword: Steel Reinforcement

Abstract: There has been increasing concern in recent years over the structural integrity of construction in Nigeria. Reinforced concrete is the primary structural material in the country, so the strength of the steel reinforcement has become a major target for scrutiny. This study reviews the reported literature on reinforcing steel strengths from tests carried out in Nigeria between 2010-2021. The characteristic strength of steel is the basis for the design of steel reinforcement in both the Eurocode and British Standards used for design in Nigeria. However, it is noted that in every case, the characteristic strength results are missing or erroneously reported. A total of 18 studies are found, and the raw data for each study is analysed to derive the characteristic strength results. An average characteristic strength of 342.4 MPa is found from all the studies, lower than the 400 MPa and 500 MPa minimums assumed in the Eurocode and British Standards respectively. The finding here indicates that the widespread methodology around interpreting the tensile testing of steel reinforcement in Nigeria needs revisiting.

Abstract: The study of liquid corrosion of cement concrete was carried out, the results of which allow to determine the mass transfer parameters in the studied system and calculate the service life of the concrete product in environments of varying degrees of aggressiveness. Dates of the beginning of electrochemical corrosion of steel reinforcement in reinforced concrete and the achievement of the limit state of steel reinforcement in the conditions of liquid corrosion of reinforced concrete in a chloride-containing medium were mathematically calculated and experimentally established. Investigations of the corrosion resistance of fiberglass reinforcement in various environments have been carried out. The possibility of replacing steel reinforcement with fiberglass when reinforcing concrete products is considered.

Abstract: Retracted paper: In high speed machining, performance is generally influenced by the dynamic behaviour of the machine tool structures. The machine tool structure is required to be rigid in order to remove the undesirable vibration and to improve the work piece quality. The most conventional material used in machine tool structure is cast iron which has both stiffness and dynamic characteristics to perform at varying speeds. The objective of this work is to improve damping capacity of vertical machining centre column. The damping capacity of column can be increased further by using passive damping method of ball packing. Damping capacity is a crucial factor which makes the dissipation of vibration happens at faster rate. As compared with cast iron established studies shows that epoxy granite a composite material improves damping capacity. Epoxy granite though could be a good choice for improving the machine tool performance at high speeds but is poor in static stiffness compared to cast iron. In this investigation it was observed that, the static stiffness of epoxy granite composite vertical machining centre column could be increased by using steel reinforcements. The final results reveal that, steel balls with epoxy granite provide faster dissipation time of 15ms at 70% packing ratio as compared to glass balls that showed dissipation time of 35ms. Also it was seen that, the steel balls offer the better damping capacity at optimum packing ratio of 50% mainly due to its specific gravity and mass of the balls.

Abstract: The number of destroyed cities in Iraq has increased significantly over the last five years. It presents a negative impact on the country's economy on the one hand and on the environment on the other. Reconstruction of these cities requires substantial capital to provide building materials needed for reconstruction and this leads to depletion of natural resources. This paper aims at finding an effective management method that contributes to the investment of the remnants of the components of destroyed buildings, including reinforcing steel, using the building information modelling (BIM) technique. The results showed that the amount of steel reinforcement that can be obtained from the destroyed buildings is enormous. Therefore, these quantities must be addressed through reusing or recycling. The sale of these quantities as recycling materials can provide a large income which can be added to the capital of the project.

Abstract: The contribution focuses on the effect of selected input parameters on probabilistic estimation of chloride induced reinforced concrete bridge deck corrosion initiation. The reinforced concrete bridge deck with steel protected by epoxy-coating is considered. A finite element diffusion model in conjunction with a probabilistic method using Monte Carlo technique is used to address the inherited randomness of input variables. Presented parametric study shows the sensitivity of estimation of the corrosion initiation likelihood on variation of input parameters.

Abstract: Vital problem, occurring in the operation process of structures such as timber beams, is the increase of their bearing capacity and span length with keeping their height. One of the possible ways to solve this problem is steel reinforcement of such structures. The aim of the research work is to show possibility of increasing bearing capacity of single-span reinforced timber beams and develop the main points of calculation and design of such structures. The beam is reinforced symmetrically by 2 rods d28 with both sides with A_r=24.63 cm² (4d28 A300). The reinforcement is placed in compressed and stretched areas. Reinforced timber structures are designed on two groups of limit conditions. Design on the first limit condition (normal and tangential stress) is made using geometric characteristics of rectangular section of reinforced timber beam. Design on the second limit condition is made taking onto account the timber elastic nodule and inertia moment for reinforced timber beam. The main features of joint work of timber and reinforcement, which can increase operation reliability of bearing structures, are shown in the research work.

Abstract: The review of the main physical and mechanical characteristics of steel and nonmetallic composite reinforcements is presented in the article. Also there are complex studying, analysis and synthesis of available information. Much attention is paid to recommendations for designing building constructions of different functions with nonmetallic composite reinforcements. Scopes of nonmetallic composite reinforcements in the construction industry in Russia and abroad are considered.Information about main producer and the official distributor of composite reinforcements is provided in the article. This company is the official distributor in the Northwest of the Russian Federation. Their production is successfully used on many objects under construction in Russia. Materials of the article are based on the real photographic materials provided by personal archive of the company.

Abstract: With the improvement of requirements for the building, and the effects of various factors for some existing steel structure building during the long-term service process, structural function is damaged, which requires reinforcement for existing structures to meet the requirements of its use of the function. This paper systematically introduces the research and application of steel structure member on strengthening aspects, which is prepared for the research of steel column reinforced by enclosed reinforced concrete under axial compression with initial compressive load. According to development and characteristics of steel columns reinforced by enclosed reinforced concrete under axial compression, this paper analyzes the common working mechanism of steel structure and concrete after reinforcement, and introduces the calculation method and its engineering application in our country.

Abstract: Analysis of force transmission through the various structural components is needed to the full understanding of the seismic behavior of masonry buildings. It is in fact necessary to identify the weak links of the chain and define the essential reinforcements to insert in the structure. In this context the Paper analyzes the strengths of masonry walls under the action of out of plane and in plane horizontal forces and compares the systems of reinforcement of the walls that can use steel or Fiber Reinforced Polymers (FRP).

Abstract: Along with our country economy fast development, the building and renovation is becoming more and more widely, layer for steel structure system, relying on its obvious advantages, has gradually become one of hot topics in the study of engineering. Combining with engineering example, through the integrity research, bearing capacity calculation, field exploration, the analysis of the concrete strength testing, etc., has carried on the appraisal on the safety of building structure, and analyses the feasibility of after add layer. In layer for steel structure design, at the same time puts forward the design and construction of some key points, provide a reference for similar projects.