TIMBER HOUSE STRUCTURE WITH URUGUAYAN WOOD DEVELOPMENT OF STRUCTURAL METHOD AND STUDY ON STRUCTURAL PERFORMANCE

摘要

Uruguay has an increasing forested area. This led to a huge production of wood in near future. Then the government of Uruguay will promote the construction of wooden houses. In 2000, the Technological Laboratory of Uruguay (LATU) with the support of JICA started the research to understand and to obtain the mechanical properties of Uruguayan wood. Eucalyptus Grandis, Elliotis Pines and Tadea Pines were selected for the research. Recent research demonstrated the feasibility of their use in structure and also using the most traded sections in the region, having the result of LATU and JICA as information. The first challenge for this project was to design the structure entirely with four sections 1"×6", 2"×6", 2"×12", and 5"×5" inches. To develop the wooden structure project, we applied the Timber frame structure of Japan and Wood-Frame Construction of North America, and the Japanese standards for structural design of timber structures were employed. Although Uruguay is not located in a seismic zone, it is necessary to provide appropriate horizontal resistance to analyze and prove the wooden structure, so the application of this study can be extended to others countries of South America which are located in seismic zone or like Japan in different location but with heavy earthquake conditions with the intention to promote the use of this kind of wood. Many examples in relation to earthquake behavior and the earthquake resistance of wooden structure are available in Japan. Those techniques were used as reference for this project. Special attention has been paid to the frame joints, where Japanese standards are used, and additionally the applicability of some special joints, recently investigated in Japan on special conditions. The geographic area where Uruguay is located, with unexpected flood and heavy rain season in winter, as well as the growing increase in rainfall and relative humidity due to the phenomenon of "El Nino forecast" generate new challenges. The critical factor refer that relative humidity (RH) variation in the ambient air, and thus varying moisture content, reduce the load bearing capacity of individual timber elements. Dependent on how fast the RH changes the mechanical properties and dimensions, it's possible elaborates a feasible procedure to reduce this problem. The combination of Uruguayan wood with international methods of construction could contribute to develop an adequate structural solution that consider the seismic behavior and weather conditions.