Numerical analysis of structural behavior of welded wire reinforcement in reinforced concrete beams

Thesis (M.S.) University of Alaska Fairbanks, 2016Modernization and industrialization have paved the way for the construction industry of India to expand. On the other hand the Indian construction industry is set to face an acute workforce shortage. The shortage of construction workers has in fact slowed down the growth of this industry in major cities across the country and escalated its cost by 40 percent. An alternative way to replace the labor force is by automation techniques. This study is a numerical analysis to evaluate structural behavior of simply supported concrete beams reinforced with welded wires in comparison with mild steel reinforced concrete beams. Welding conventional steel bars (60 ksi) reduces their shear strength by 50 percent. Welded Wire Reinforcement (80 ksi), with its greater strength, higher durability, significantly lower placing and overall cost, provides an alternative and perhaps a better substitution for mild steel bars. The commercial finite element analysis program, ABAQUS, was used to model the non-linear behavior of reinforced concrete beams. In order to evaluate the structural behavior of welded wire reinforced concrete beams, different configurations of longitudinal and transverse wires have been considered. First, different types of stirrup configurations in a rectangular reinforced concrete beam are compared with a conventional reinforced beam. Second, a structurally performing welded wire configuration is compared with a Mexican chair styled reinforcement configuration. This part of the analysis is evaluated for a T–beam, used for building roof applications.Chapter 1 Introduction -- Welded Wire Reinforcement -- Traditional Rebar versus Welded Wire Reinforcement (WWR) -- Potential Gains through Welded Wire Reinforcement (WWR) -- Welded Wire Reinforcement Specifications and Nomenclature -- Welded Wire Reinforcement Manufacturing, Handling and Placing -- Aim and Scope -- Outline of Thesis -- Chapter 2 Literature Review -- Impact of Welded Wire Reinforcement in Structural Members -- Welded Wire Reinforcements in Columns -- Welded Wire Reinforcements in Beams and Girders -- Welded Wire Reinforcements in Structural Walls -- Summary -- Chapter 3 Finite Element Modeling of Reinforced Concrete Beams -- ABAQUS Modeling -- Non-linear Behavior of Concrete -- Uniaxial and Biaxial Behavior -- Non-linear Modeling of Reinforced Concrete Beam -- Material Model Properties -- Concrete Damage Plasticity Parameters -- Reinforcement Properties -- Convergence Analysis -- Chapter 4 Numerical Analysis of Concrete Beams Reinforced with Traditional and Welded Wire Reinforcement -- Introduction -- Initial Validation and Mesh Convergence -- Analysis of Welded Wire Reinforcement Grids in Reinforced Concrete Beams -- Rectangular Reinforced Concrete Beams Subjected to Four Point Loading Condition -- Rectangular Reinforced Concrete Beams Subjected to Uniformly Distributed Loading Condition -- T - Beams Subjected to Four Point Loading Condition -- Chapter 5 Conclusion and Recommendation -- Conclusion -- Recommendation -- References

Mathematical model for the dc-ac inverter for the Space Shuttle

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