Mild steel is relatively low-cost and easily accessible material to fabricate some structural members. It would be a significant advantage if seismic energy dissipaters that are used in structures constructed in the earthquake prone areas, could also be produced on site. In this paper, a promising seismic energy dissipater made of mild steel, so-called steel cushion (SC) is presented. It is provided experimental and analytical responses of SCs subjected to bi-axial loadings. SC rolls under the lateral loading that allows relocation of the plasticized cross-section. Henceforth, SC dissipates considerable amount of seismic energy. A series of tests were performed to achieve experimentally the behavior of SC subjected to longitudinal and transversal loading. Finite Element Models (FEMs) were also generated to reproduce the experimental backbone curves and to predict the bi-directional response properties for discrete transversal forces and plate thicknesses. Closed-form equations were derived to determine yield and ultimate forces and the corresponding displacements as well as location of the plasticized sections. The behavior of SC could either be projected by the FEMs with the exhibited parameters or by means of the proposed closed-form equations and the normalized design chart.
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Energy dissipative steel cushions (EDSCs) are simple units that can be used to join structural members. They can absorb a substantial amount of seismic energy due to their geometric shapes and the ductile behavior of mild steel. Large deformation capability and stable hysteretic behavior were obtained in monotonic and cyclic tests of EDSCs in the framework of the SAFECLADDING project. Discrete numerical modeling strategies were applied to reproduce the experimental results. The first and second models comprise two-dimensional shell elements and one-dimensional flexural frame elements, respectively. The uncertain points in the preparation of the models included the mesh density, representation of the material properties, and interaction between contacting surfaces. A zero-length nonlinear link element was used in the third attempt in the numerical modeling. Parameters are recommended for the Ramberg–Osgood and bilinear models. The obtained results indicate that all of the numerical models can reproduce the response, and the stiffness, strength, and unloading and reloading curves were fitted accurately.
This chapter reports on the findings of a research project aimed at investigating the actual thermal environment of the housing of older occupants (aged 65 or over) in South Australia. The study documented their thermal preferences and behaviours during hot and cold weather and relationships to their well-being and health. Information was collected in three phases, a telephone survey, focus group discussions and detailed house environmental monitoring that employed an innovative data acquisition system to measure indoor conditions and record occupant perceptions and behaviours. The research covered three climate zones and extended over a nine-month period. The detailed monitoring involved a total of 71 participants in 57 houses. More than 10,000 comfort/well-being questionnaire responses were collected with more than 1,000,000 records of indoor environmental conditions. Analysis of the data shows the relationships between thermal sensation and self-reported well-being/health and the various adaptive strategies the occupants employ to maintain their preferred conditions. Findings from the research were used to develop targeted recommendations and design guidelines intended for older people with specific thermal comfort requirements and more broadly advice for architects, building designers and policymakers. Original publication at: Routledge Handbook of Resilient Thermal Comfort Chapter 7: https://doi.org/10.4324/9781003244929-10
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