A Simple Critical Response Evaluation Method for Base-Isolation Building-Connection Hybrid System Under Double Impulse as Representative of Near-Fault Ground Motion

We revisit a unique building system including a base-isolation, building-connection hybrid control system. The base-isolation system withstands pulse-type earthquake ground motions effectively and the building-connection system resists long-duration earthquake ground motions efficiently. A simple smart critical response evaluation method without nonlinear time-history response analysis is proposed for this hybrid building system under near-fault ground motions. An analytical expression of the maximum elastic-plastic deformation of a damped bilinear hysteretic single-degree-of-freedom (SDOF) model under critical double impulse as a representative of pulse-type ground motions derived in our previous paper plays an important role in the development of the simple critical response evaluation method. A two-step transformation procedure into an SDOF model is proposed. The first step is the transformation of the main base-isolated building into an SDOF system and the second step is the reduction of the connecting dampers supported on a sub building to a damper with a sophisticated compensation factor on an assumed rigid wall. The evaluation of damping coefficients with the consideration of yielding of the base-isolation story is a key step in this paper. Different from the previous work, the equivalent damping coefficient is derived depending on the response range before and after yielding of the base-isolation story. This treatment enhances the accuracy of the proposed method. The accuracy and reliability of the proposed response evaluation method is demonstrated by the time-history response analysis of the multi-degree-of-freedom (MDOF) model.

Base Isolation Compared To Capacity Design For Large Corner Periods And Pulse-Type Seismic Records

Southern Romania experiences special soil conditions, leading to rather long corner periods and to an enlarged plateau of the response spectrum, with associated large displacement demands. Pulse-type ground acceleration records complete this unique seismic area. Research on the seismic behavior of structures built under these special conditions is limited and engineers are not comfortable with alternative solutions such as base isolation. This study investigates the seismic performance of a hospital building with the following two anti-seismic solutions: 1) stiffening, in line with the capacity design method and 2) base isolation. Base shear, structural drift and structural acceleration are compared for both approaches.

Potential of Pulse Flours as Partial Meat Replacers in Heat-Treated Emulsion-Type Meat Sausages

Reformulation approaches in the meat industry are required to promote nutritional improvement, health functionality, and reduce environmental impact. A relevant approach among these is to reduce the amount of meat in meat products. Reduced-meat products should maintain or improve the sensory characteristics and nutritive value compared to conventional meat products. Among meat products, heat-treated emulsion-meat sausages are widely consumed and especially suitable for reformulation approaches. Due to its high protein content, with high functionally and biological value, pulse flour has a high potential to be used as meat replacer. Most studies regarding the replacement of meat with pulses have been made on fresh meat preparations where amounts of up to 15% of pulse flour did not negatively affect sensory quality while increased yield and firmness. However, studies using pulse flour in emulsion-type sausages are scarce. Further research is warranted to optimize the reformulation of these meat products using flour pulses. The topics to be addressed are the following: effects of pulse type, pulse pretreatments, such as soaking or germination, pulse flour treatments before incorporation into the meat mix, combination of pulses with other proper ingredients, and heat treatment intensity on the pulse antinutrient inactivation and the technological and edible quality traits of the pulse-containing sausages.

Active Gaits Generation of Quadruped Robot Using Pulse-Type Hardware Neuron Models

In this chapter, the authors will propose the active gait generation of a quadruped robot. We developed the quadruped robot system using self-inhibited pulse-type hardware neuron models (P-HNMs) as a solution to elucidate the gait generation method. We feedbacked pressures at the robot system’s each foot to P-HNM and varied the joints’ angular velocity individually. We experimented with making the robot walk from an upright position on a flat floor. As a result of the experiment, we confirmed that the robot system spontaneously generates walk gait and trot gait according to the moving speed. Also, we clarified the process by which the robot actively generates gaits from the upright state. These results suggest that animals may generate gait using a similarly simple method because P-HNM mimics biological neurons’ function. Furthermore, it shows that our robot system can generate gaits adaptively and quite easily.

Inelastic response spectra of self-centering structures with the flag-shaped hysteretic response subjected to near-fault pulse-type ground motions

Many studies on the inelastic response spectra have mainly focused on structures with the conventional hysteretic behavior. However, for self-centering structures with the flag-shaped (FS) hysteretic behavior, the corresponding study is limited. The primary aim of this study is to investigate the inelastic response spectra of self-centering structures with FS hysteretic behavior subjected to the near-fault pulse-type ground motion. To this end, the smooth FS hysteretic model based on Bouc–Wen model is developed, and the characteristics of pulse-type ground motions are described in detail. It is found that the general features of inelastic response spectra of the FS model are sensitive to the acceleration-, velocity-, and displacement-sensitive spectral regions of the ground motion. The inelastic displacement, velocity, acceleration, and ductility factor spectra of the FS hysteretic model for pulse-type ground motions are much larger than those for ordinary ground motions, while the residual displacement spectra under the two types of ground motions are both very small due to its self-centering capacity. Moreover, the inelastic response spectra are affected by the ground motion characteristics and structural hysteresis behavior, especially the large pulse period and peak ground velocity (PGV) significantly increase the inelastic displacement, velocity, and acceleration spectra.