Dual – loop force – displacement mixed control strategy and its application on the quasi – static test

The Quasi-static test is a well-known powerful methodology to evaluate the seismic performance of structural components and systems. One of the most important challenges in the Quasi-static testing is to achieve precise boundary conditions, especially for the axial loading of vertical components. The requirement of synchronized displacement loading and target axial force formed a pair of contradiction. A dual-loop force-displacement mixed control strategy is proposed. The presented approach is successfully verified through the quasi-static testing for a full-scale concrete filled steel tube column. The control targets are achieved with an excellent control performance

A novel sectional constitutive model for beam-column element

The constitutive models on sectional level can meet both computational accuracy and efficiency, and hence have great potential for nonlinear analyses of frame structures. However, currently available sectional constitutive models usually assume a constant axial force and therefore cannot account for axial force and bending moment coupling flexibly. In this paper, a sectional constitutive model is proposed in the framework of classical plastic theory. The proposed model features kinematic/isotropic hardening. It can well account for axial flexure interaction, and can be used to describe distributed plasticity along beam-column members in comparison with a plastic hinge model. The numerical simulations of a cantilever column and a steel frame structure showed that the proposed sectional constitutive model is more accurate than a plastic hinge model and more efficient than a fiber model

Creative destruction in science

Drawing on the concept of a gale of creative destruction in a capitalistic economy, we argue that initiatives to assess the robustness of findings in the organizational literature should aim to simultaneously test competing ideas operating in the same theoretical space. In other words, replication efforts should seek not just to support or question the original findings, but also to replace them with revised, stronger theories with greater explanatory power. Achieving this will typically require adding new measures, conditions, and subject populations to research designs, in order to carry out conceptual tests of multiple theories in addition to directly replicating the original findings. To illustrate the value of the creative destruction approach for theory pruning in organizational scholarship, we describe recent replication initiatives re-examining culture and work morality, working parents\u2019 reasoning about day care options, and gender discrimination in hiring decisions. Significance statement It is becoming increasingly clear that many, if not most, published research findings across scientific fields are not readily replicable when the same method is repeated. Although extremely valuable, failed replications risk leaving a theoretical void\u2014 reducing confidence the original theoretical prediction is true, but not replacing it with positive evidence in favor of an alternative theory. We introduce the creative destruction approach to replication, which combines theory pruning methods from the field of management with emerging best practices from the open science movement, with the aim of making replications as generative as possible. In effect, we advocate for a Replication 2.0 movement in which the goal shifts from checking on the reliability of past findings to actively engaging in competitive theory testing and theory building. Scientific transparency statement The materials, code, and data for this article are posted publicly on the Open Science Framework, with links provided in the article

A novel sectional constitutive model for beam-column element

The constitutive models on sectional level can meet both computational accuracy and efficiency, and hence have great potential for nonlinear analyses of frame structures. However, currently available sectional constitutive models usually assume a constant axial force and therefore cannot account for axial force and bending moment coupling flexibly. In this paper, a sectional constitutive model is proposed in the framework of classical plastic theory. The proposed model features kinematic/isotropic hardening. It can well account for axial flexure interaction, and can be used to describe distributed plasticity along beam-column members in comparison with a plastic hinge model. The numerical simulations of a cantilever column and a steel frame structure showed that the proposed sectional constitutive model is more accurate than a plastic hinge model and more efficient than a fiber model

Application of the Energy-Conserving Integration Method to Hybrid Simulation of a Full-Scale Steel Frame

The nonlinear unconditionally stable energy-conserving integration method (ECM) is a new method for solving a continuous equation of motion. To our knowledge, there is still no report about its application on a hybrid test. Aiming to explore its effect on hybrid tests, the nonlinear beam-column element program is developed for computation. The program contains both the ECM and the average acceleration method (AAM). The comparison of the hybrid test results with thesetwo methods validates the effectiveness of the ECM in the hybrid simulation. We found that the energy error of hybrid test by using ECM is less than that of AAM. In addition, a new iteration strategy with reduction factor is presented to avoid the overshooting phenomena during iteration process with the finite element program