Alexander Salenikovich

Identification of multiple criteria for the evaluation of light-frame wood wall assemblies

Design of light-frame wood wall assemblies should consider several performance criteria. Possible alternatives must respect minimum code requirements for the studied context. Then, additional performance characteristics may be considered to achieve the most suitable configuration for a specific project. It is, however, not simple to define how several performance criteria can be evaluated simultaneously and which scale should be used to compare assemblies. Existing tools to evaluate performance criteria consider mostly one parameter at the time. An evaluation methodology taking into account at once different performance characteristics would be beneficial in the decision process. With the final aim of developing a multi-criteria framework to support the evaluation of improved factory-built wood-frame exterior walls, this article presents a methodology for quantitative evaluation of a set of performance characteristics. The identification of appropriate criteria is followed by the choice of quantification mechanisms. A case study comparing five wall assemblies exemplifies this methodology.

Multicriteria decision analysis applied to the design of light-frame wood wall assemblies

Designers of light-frame wood wall assemblies should consider several performance criteria simultaneously in addition to minimum requirements set by building codes. Evaluation of various performance characteristics can help select the most suitable configuration for a given project in a given context. In a previous article, we identified appropriate criteria and explored their means of evaluation. Following up, this article integrates the context and the preference of the decision-maker and seeks to obtain a ranking of the various alternatives using quantitative and qualitative information. Four multicriteria decision analysis (MCDA) techniques are explored: weighted sum, MACBETH, ELECTRE II, and PROMETHEE. The approach is applied to a case study where five wall assemblies are compared within six different decision contexts. It shows how the choice of the appropriate aggregation method depends on the nature of the performance evaluation scales and demonstrates the usefulness of MCDA to consider simultaneously different aspects of wall performance.

RACKING AND BENDING TESTS FOR PREFABRICATED WALL PANELS

El objetivo de este estudio fue evaluar y optimizar conexiones lineales “muro a muro” utilizadas en la instalacion de muros de madera prefabricados para casas. Los resultados de 6 tests de cizallamiento y 9 tests de flexion realizados en muros de 2.44 x 2.44 m son presentados a continuacion. Los muros fueron prefabricados a partir de dos segmentos de 1.22 x 2.44 m conectados con tres tipos de conexion. Los tests de cizallamiento fueron realizados de acuerdo a las indicaciones presentes en la norma ASTM, y dos conexiones diferentes a los cimientos fueron utilizadas. Los tests de flexion fueron llevados a cabo utilizando un protocolo de carga propuesto, ideado a partir del calculo de la presion de viento ejercida perpendicularmente a los muros. Para estos tests, tres tipos de conexion a los cimientos fueron utilizadas. En los tests de cizallamiento, los resultados demuestran que el tipo de conexion utilizada entre los muros no incide significativamente en la resistencia de los muros anclados a los cimientos, mientras que, para los muros clavados a los cimientos, la capacidad de resistencia no fue alcanzada. Respecto a los tests de flexion, los muros resistieron alta presion de viento, independiente del tipo de conexion muro a muro utilizada. Los resultados seran usados para validar un modelo preliminar de elementos finitos, desarrollado para predecir el comportamiento de muros prefabricados ante solicitaciones de cizallamiento y de flexion, con especial atencion en la optimizacion de la conexion muro a muro y del anclaje a los cimientos