@article{gupta_rustogi_gupta_1999, title={Ritz vector approach for evaluating incabinet response spectra}, volume={190}, ISSN={["0029-5493"]}, DOI={10.1016/S0029-5493(99)00076-X}, abstractNote={A new method is proposed for evaluating accurate incabinet response spectra for seismic qualification of electrical instruments. Finite element analysis of several typical cabinets shows that only few (often one) modes contribute significantly to the spectral accelerations at critical instrument locations inside the cabinet. In most cases the significant mode is a local mode of the cabinet component like door or back wall on which the instrument is mounted. In some cases it can also be a global cabinet mode or a superposition of the global cabinet and local component modes. Dynamic properties of the significant modes can be calculated using Rayleigh–Ritz method. The engineering effort and computational time taken by the new method is a minute fraction of that by the finite element method.}, number={3}, journal={NUCLEAR ENGINEERING AND DESIGN}, author={Gupta, A and Rustogi, SK and Gupta, AK}, year={1999}, month={Jun}, pages={255–272} }
@article{borden_shao_gupta_1998, title={Dynamic properties of Piedmont residual soil - Closure}, volume={124}, DOI={10.1061/(ASCE)1090-0241(1998)124:6(554)}, number={6}, journal={Journal of Geotechnical and Geoenvironmental Engineering}, author={Borden, R. H. and Shao, L. S. and Gupta, A.}, year={1998}, pages={554–555} }
@article{gupta_gupta_1998, title={Missing mass effect in coupled analysis. I: Complex modal properties}, volume={124}, DOI={10.1061/(asce)0733-9445(1998)124:5(490)}, abstractNote={New formulations are developed to account for the effect of uncalculated high frequency rigid modes in the seismic analysis of coupled primary–secondary systems by modal synthesis approach. The effect of uncalculated rigid modes is included in terms of residual modal vectors for both the uncoupled primary and the multiply supported secondary systems. The reduced eigenvalue problem, obtained by transforming the original equation of motion in which the displacements at the secondary system degrees of freedom (DOF) are expressed relative to the base of the primary system, gives incorrect results when all the modes of the secondary system are not included and the effect of high frequency modes is included through residual modal vectors. An alternate formulation is presented in which the original equation of motion is transformed such that the displacements at the secondary system DOF are expressed relative to the primary system connecting DOF. The reduced eigenvalue problem is solved using the transformed equ...}, number={5}, journal={Journal of Structural Engineering (New York, N.Y.)}, author={Gupta, A. and Gupta, A. K.}, year={1998}, pages={490–495} }
@article{gupta_gupta_1998, title={Missing mass effect in coupled analysis. II: Residual response}, volume={124}, DOI={10.1061/(asce)0733-9445(1998)124:5(496)}, abstractNote={This is the second paper of two papers that describe the procedures to include the effect of uncalculated high frequency modes in coupled modal synthesis. Because the residual modal vectors of a multiply supported secondary system cannot be included directly in a coupled modal synthesis, formulations are developed to calculate the residual response due to “missing mass” contained in the uncalculated high frequency rigid modes and combine it with the response due to nonrigid modes. A criterion is developed to determine a rigid (cut-off) frequency for the uncoupled secondary system modes and estimate the upper bound of error in the secondary system residual response.}, number={5}, journal={Journal of Structural Engineering (New York, N.Y.)}, author={Gupta, A. and Gupta, A. K.}, year={1998}, pages={496–500} }
@book{gupta_gupta_1997, title={CREST-IRS: A computer program for generating instructure response spectra (Version 1.0)}, publisher={Center for Nuclear Power Plant Structures, Equipment and Piping in the Department of Civil Engineering}, author={Gupta, A. and Gupta, A. K.}, year={1997} }
@article{gupta_gupta_1997, title={Seismic response of tuned single degree of freedom secondary systems}, volume={172}, ISSN={["0029-5493"]}, DOI={10.1016/S0029-5493(96)00003-9}, abstractNote={Modal synthesis procedure for evaluating spectral acceleration in the single degree of freedom (SDOF) secondary system oscillator is studied. Problems encountered in the evaluation of response for secondary oscillators that are tuned or nearly tuned with the primary system modes are discussed and solutions to these problems are presented. A new hybrid approach is proposed that gives accurate spectral acceleration in tuned secondary systems for both cases of zero and non zero mass ratio in structures that are nonclassically damped. Formulations are developed to evaluate the interaction-free (zero mass ratio) instructure spectral accelerations for perfectly tuned secondary oscillators in a coupled primary-secondary system when the two uncoupled systems have same damping characteristics (classical damping case).}, number={1-2}, journal={NUCLEAR ENGINEERING AND DESIGN}, author={Gupta, A and Gupta, AK}, year={1997}, month={Jul}, pages={17–25} }
@book{ajaya kumar gupta_1993, title={Guidelines for design of low-rise buildings subjected to lateral forces}, publisher={Boca Raton: CRC Press}, author={Ajaya Kumar Gupta, Peter James Moss}, year={1993} }