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Recent strong earthquakes have shown that column failure is the primary cause of collapse in many existing older buildings and bridges. The main objective of this paper is to develop a macromodel to simulate the cyclic lateral load--deformation response of reinforced concrete columns with limited computational effort. Flexural, longitudinal bar slip, and shear deformations are predicted under monotonic lateral loads, including the effects of strength decay and stiffness degradation. Using these monotonic responses as envelopes or primary curves, cyclic responses corresponding to these three deformation components are calculated. The column under consideration is classified into one of five categories considering the potential for flexural, shear, or axial load failure. Individual cyclic responses then are combined to obtain the total lateral response of the column based on its identified failure mode. Comparison of predicted cyclic response and experimental data showed that the proposed model is sufficiently accurate. DOI: 10.1061/(ASCE)0733-9445(2009)135:2(139) CE Database subject headings: Reinforced concrete; Concrete columns; Shear resistance; Shear failure; Axial loads; Cyclic loads.

In this paper, we present the first interior solutions representing compact stars in κ (ℛ ,) gravity by solving the modified field equations in isotropic coordinates. Further, we have assumed the metric potentials in Schwarzschild's form and a few parameters along with the isotropic condition of pressure. For solving, we use specific choice of the running gravitational constant as κ (ℛ ,) = 8 π − λ (G = c ̃ = 1). Once arrived at the reduced field equations, we investigate two solutions with c = 1 and c ≠ 1 , where c denotes here another constant that should not be confused with the speed of light. Then, we investigate each solution by determining the thermodynamics variable viz pressure, density, speed of sound and adiabatic index. We found that these solutions satisfy the Bondi criterion, causality condition and energy conditions. We also found that the M − R curves generated from these solutions satisfy the stringent constraints provided by the gravitational wave observations due to the neutron star merger GW 170817. [ABSTRACT FROM AUTHOR]