Stairs

Background Transtibial amputees encounter stairs and steps during their daily activities. The excessive pressure between residual limb/socket may reduce the walking capability of transtibial prosthetic users during ascent and descent on stairs. The purposes of the research were to evaluate the interface pressure between Dermo (shuttle lock) and Seal-In X5 (prosthetic valve) interface systems during stair ascent and descent, and to determine their satisfaction effects on users. Methods Ten amputees with unilateral transtibial amputation participated in the study. Interface pressure was recorded with F-socket transducer (9811E) during stair ascent and descent at self-selected speed. Each participant filled in a questionnaire about satisfaction and problems encountered with the use of the two interface systems. Findings The resultant mean peak pressure (kPa) was significantly lower for the Dermo interface system compared to that of the Seal-In X5 interface system at the anterior, posterior and medial regions during stair ascent (63.14 vs. 80.14, 63.14 vs. 90.44, 49.21 vs. 66.04, respectively) and descent (67.11 vs. 80.41, 64.12 vs. 88.24, 47.33 vs. 65.11, respectively). Significant statistical difference existed between the two interface systems in terms of satisfaction and problems encountered (P < 0.05). Interpretation The Dermo interface system caused less pressure within the prosthetic socket compared to the Seal-In X5 interface system during stair negotiation. The qualitative survey also showed that the prosthesis users experienced fewer problems and increased satisfaction with the Dermo interface system. © 2013 The Authors.

http://ac.els-cdn.com/S0268003313002106/1-s2.0-S0268003313002106-main.pdf?_tid=844f5de0-a018-11e3-8732-00000aab0f6b&acdnat=1393551471_17967ebcb8bca05fbeb53866396eb303 
http://www.ncbi.nlm.nih.gov/pubmed/24161521

The purpose of this study was to assess the safety of a winding glass stairway by observing the behavior of stair users and to identify issues that should be studied in a laboratory setting. A checklist for coding stair use behaviors was developed. Video observations were conducted in a retail store with a glass stairway (GS) and a shopping mall with a conventional stairway (CS). Key behaviors related to safety (tread gaze, diverted gaze, handrail use) and stair incidents on the two stairways (GS and CS) were identified from the recordings and compared. On the glass stairway, more users glanced down at the treads (GS: 87% vs. CS: 59%); fewer users diverted their gaze away from the stairs (GS: 54% vs. CS: 67%); and handrail use was higher (GS: 32% vs. CS: 24%). Incident rates were much higher on the glass stairway (6.2%) compared to the conventional stairway (0.7%). Walking on winding treads made of glass may be more dangerous than walking on conventional materials due to reduced visibility of the tread edge or reduced friction between shoes and treads. Recent laboratory research suggests that stairway users may behave more cautiously using stairways with glass treads but the results from this study demonstrate that the benefit of increased caution can be negated in real world conditions.

Slender monumental stairs are major architectural features in many high-end building structures. Architectural requirements for these are usually very aggressive, with long spans and slender stringers being the norm. The resulting low natural frequencies are often within reach of the lower harmonics (which have high amplitudes) of the vertical force caused by a person descending the stair. Also, some configurations with very low frequency lateral vibration modes might allow high lateral accelerations. Because the potential for annoying vibrations is high, it is critical that stair designers have access to evaluation methods. Current evaluation methods rely on finite-element analysis-based response prediction methods that are outside the reach of many structural engineering firms. This paper presents a simplified vertical acceleration prediction method, based on the fundamental natural mode of the stair, which is suitable for manual calculations. Response predictions are compared to experimental measurements to calibrate the prediction method for design use. Lateral vibrations are discussed, and an evaluation method is proposed. Finally, a numerical example is provided. DOI: 10.1061/(ASCE)ST.1943-541X .0001256. © 2015 American Society of Civil Engineers.

Fire research has provided engineers with practical models and data that can be used to undertake perforinance based fire engineering analysis. This form of analysis is demonstrated in the development of a fire safety design strategy for the National Gallery of Victoria which required a significant upgrade of fire safety measures. As part of the development of the fire safety strategy, the analysis undertaken required input on evacuation times as part of an egress study. A full evacuation of the Gallery provided valuable data to coinpare with EVACNET+ model predictions. Experiinental evacuation data and observations of human behaviour were consistent with other research in this field alld highlighted a number of issues that fire safety designers and regulators need to take into account in the design and operation of buildings. In particular, the evacuation raised serious issues about the use of fire rated stairs in public buildings.

Previously, the study of 3D joint angle has been proven to give better interpretations on the joint and muscular activities. However, it has not been widely discovered and usually limited to normal subject and level walking activity. The inspiration of the study was based on the fact that, the obesity and staircase activity factors will significantly influence the mechanics of a joint. It has been proven significantly affected the knee rather than the hip which leading to the knee osteoarthritis disease. Moreover, since to date no experimental study has reported on hip 3D joint mechanics associating with these two factors, therefore, the analysis of hip 3D joint angle for obese and normal individuals during stair ascending activity have been proposed in order to help the hip 3D joint interpretations. Our hypothesis is that, it is hard to describe the difference of the gait strategy used between obese and normal individuals due to the effect of the mechanics adaptations of the hip joint. Therefore, with the aid of hip 3D joint angle interpretations, it is believed that these phenomena can be successfully described and investigated. The result seems to confirm that, at the late stance of stair ascending activity, the obese individuals seem to have an alternative strategy of mainly hip resistance compared to the normal' strategy of mainly hip stabilization. Otherwise, the normal and obese individuals seem to have a similar strategy of mainly hip stabilization. In addition, the obese seem to absorb or generate energy with systematically lower proportion of the 3D joint moments than normal individuals. © 2011 Springer-Verlag.

http://download.springer.com/static/pdf/845/chp%253A10.1007%252F978-3-642-21729-6_43.pdf?auth66=1393724075_e5f7595bca07a8c2fb6b12704beba604&ext=.pdf 
http://link.springer.com/chapter/10.1007/978-3-642-21729-6_43

La obra del arquitecto almeriense Fernando Cassinello Pérez (Almería, 1928-Madrid, 1975)ha sido escasamente publicada a pesar de ser prolífica y de calidad. El desarrollo de su profesión descansa sobre tres pilares: la producción arquitectónica, la actividad académica y la inquietud investigadora. Cassinello encontró en las escaleras un elemento donde depositar el ingenio creativo y un tema sobre el que escribir e investigar, además de transferir ese conocimiento a sus propias obras de Arquitectura. Las proyectó voladas, helicoidales y semicirculares. Las construyó de acero y de hormigón, directamente en la obra o con elementos prefabricados: en todos los casos recibieron con agrado las huellas que imprime el proceso de construcción. Las moldeó escultóricas o las resolvió con una eficacia ingenieril, pero siempre hubo una reflexión estructural, constructiva y proyectual sobre lo que significa subir al hogar o bajar al jardín. Unas veces, el interés residía en la escalera propiamente dicha; otras, en la caja contenedora, donde celosías caladas, muros de hormigón o de ladrillo convertían el movimiento vertical es un sensual paseo. También las barandillas, y su contacto con la mano; o los peldaños, vinculados dimensionalmente con la huella del pie, subrayan el componente antropológico de la escalera y el interés de Cassinello por su proyecto y construcción. De ellas extrajo la estricta utilitas que la modernidad les otorgó, y supo hacer de ellas, además, un elemento del paisaje urbano; un escenario de encuentro de la colectividad; e incluso, el símbolo reconocible de una obra de arquitectura. Esta investigación recoge las principales escaleras que Fernando Cassinello proyectó y construyó. Y que, desde luego, merecen ser conocidas por quien decida hoy proyectar y construir arquitectura contemporánea.

Even though, for decades, it had been accepted as an initial and critical stage in the design process, conceptual design has been inadequately supported on Computer-Aided Architectural Design (CAAD) systems. Since the computer, is by nature, proficient in high-speed calculations and data storage a wide range of tools and applications have been developed for it to enhance precision, efficiency and productivity. Only minimal achievements have been realized in exploring the territory of conceptual design—a domain that combines both creativity and problem-solving skills. This research addresses issues in existing CAAD models and argues that there must exist certain shared core constructs, or abstractions of design components that are universal and invariable. Such abstractions need to be carefully recognized and designed to capture the most fundamental and straightforward concept about the components.
For the purpose of this research, stairs have been selected as the subject of study because of their historical significance, systematic structure, and because they exist in abundance in various forms. Initially existing computer tools for stair-generation were reviewed to gather tool constraints. Then a new way of thinking regarding stair design is proposed as well as a properly defined abstraction of stairs. This abstract model is capable of modeling wide variety of stairs, including numerous special cases.
A software tool is implemented as part of AutoCAD to test the abstraction and modeling process against feasibility and coverage of cases. The tool is a relationship-based modeling environment that enables native CAD objects to be managed by relationships. A relationship-pattern ‘sequence’ is used to implement the abstraction of stairs and is used to test common and empirical stair examples. Potential applications of the Sequence pattern are far beyond stair modeling since the abstraction is so generic that it would encompass any sequential structured entity in a building. In response to the arguments made by this research, the tool also provides a set of functions for rapid modeling of an abstract design—relationship-based modeling.

Walter Benjamin utiliza en el Libro de los Pasajes la metáfora de la acción de despertar para explicar la entrada en la modernidad de la sociedad burguesa del siglo XIX. Y pone la obra de Marcel Proust como ejemplo privilegiado de este cambio. Adolf Loos en arquitectura juega un papel similar al de Proust en literatura: despoja los interiores de las casas burguesas de oscuridad y simbolismo.
La arquitectura de Loos incorpora dos rasgos del espíritu moderno: el dinamismo y la simultaneidad. Loos organiza los espacios de sus viviendas con una fuerte teatralidad. La casa se hace con una suma de escenarios simultáneos puestos en relación por juegos de escaleras múltiples y aperturas visuales. La acción de subir o bajar una escalera introduce el dinamismo del que prescindía la casa burguesa del siglo XIX. Las piezas, situadas como pequeños escenarios, convierten a sus habitantes en instantáneos actores de lo cotidiano.



In Das Passagen-Werk, Walter Benjamin uses the awakening metaphor to explain the entry into modernity of the bourgeois society in nineteenth-century. And he indicates the Marcel Proust work as a preferential example of this change. In architecture, Adolf Loos plays a similar role to Proust in literature: he eliminates darkness and symbolism from the interior of bourgeois houses.

Loos’s architecture incorporates two traits of modern spirit: dynamism and simultaneousness. Loos organizes the spaces of his dwellings with a strong theatricality. The house is the sum of simultaneous stages related by multiple sets of stairs and visual openings. The action of going up or down a stair introduces the missing dynamism in bourgeois dwellings of nineteenth-century. The rooms, situated as small stages, transform their inhabitants in instantaneous actors of day-to-day life.

Le esigenze di rappresentanza della società di corte, tradotte nell’etichetta del cerimoniale di udienza, hanno influito in modo determinante nel radicarsi sul lungo termine di pratiche poi diventate massime generali per la configurazione delle scale principali. Lo scalone di un palazzo, tanto più se di una residenza reale, corrisponde di fatto al primo passo nel percorso cerimoniale e per questo assume una forte valenza simbolica nel suo apparire. D’altro canto, per gli architetti di età moderna la scala è un tema privilegiato di riflessione e sperimentazione, che si pone quale sfida compositiva e costruttiva. Attraverso la rilettura dei progetti di Filippo Juvarra per gli scaloni del palazzo reale di Messina, di Palazzo Madama, Rivoli e da ultimo Madrid, in un confronto aperto con modelli ricercati, prima di tutto, nella cultura romana di inizio Settecento ed esperienze condotte in parallelo (come nelle corti dell’Impero), ci si interroga sul modo in cui l’architetto messinese abbia saputo soddisfare le esigenze di carattere cerimoniale ed esprimere la propria arte: come, cioè, abbia interpretato il tema progettuale dello scalone e la sua funzione di rappresentanza per trasformarli in un’occasione creativa, perseguendo il proprio ideale di architettura aperta.

En este artículo se ofrece una visión de conjunto sobre la arquitectura civil –tanto privada como pública– levantada en tierras aragonesas a lo largo del Quinientos. Partiendo del análisis de las tipologías y prestando una atención especial a las fuentes y modelos empleados, este estudio contempla sus relaciones con la arquitectura desarrollada en el reino de Navarra a lo largo de este mismo periodo.

In this article we offer an overall vision on civil architecture –private or public– applied on Aragonese land during the 16th century. Starting from the analysis of typologies and paying a particular attention to the sources and models employed, this study considers its relations with the civil architecture developed in the Kingdom of Navarre throughout the same period of time.

This paper reviews empirical studies in product modeling and issues of CAAD, and then proposes a new way of thinking in object modeling for abstract design concepts – by using stairs as the subject of study because of its systematic nature and wide variety of forms. This object model works in the higher level over existing product models and deals with abstract concept only. It provides a mean for capturing design concepts and knowledge. Most stair generator in CAAD are only capable of making regular stairs, let alone those fascinating free-form stairs. The purpose of this research is to find a higher conceptual structure of stairs by the object modeling method, so virtually all types of stairs can be described and modeled. Therefore conceptual design in CAAD would be possible and useful for designers. A prototype on AutoCAD will be implemented to demonstrate how the conceptual structure works.