%0 Journal Article
%T An芍lisis del comportamiento reol車gico y termo-higromec芍nico en probetas de tableros tensados de madera para puentes a condiciones ambientales variables Analysis of rheological and thermo-hygro-mechanical behaviour of stress-laminated timber bridge deck in variable environmental conditions
%A Macarena Figueroa
%A Cecilia Bustos
%A Peter Dechent
%A Laura Reyes
%J MADERAS : Ciencia y Tecnolog赤a
%D 2012
%I Universidad del B赤o-B赤o
%X La madera presenta un comportamiento termo-higromec芍nico cuando se somete a la acci車n conjunta de variaciones de temperatura, humedad relativa y carga mec芍nica. Los tableros tensados de madera presentan p谷rdidas de fuerza en la barra de tensado debido principalmente a la relajaci車n de la tensi車n y a la contracci車n de la madera, aumentando con los cambios de humedad y temperatura de 谷sta. El objetivo de este estudio fue estudiar el comportamiento reol車gico de tableros tensados de madera de pino radiata (Pinus radiata D. Don) sometidos a cambios de temperatura y humedad relativa. Un total de 16 probetas fueron previamente tratadas con diferentes tratamientos de preservaci車n, las cuales fueron sometidas a cuatro ciclos de temperatura y humedad relativa en una c芍mara de clima. La deformaci車n de las probetas y la tensi車n de las barras de acero fueron medidas. Los resultados mostraron que la variaci車n de la temperatura y de la humedad tiene una fuerte influencia en la variaci車n de la tensi車n de las barras tensoras. Los retensados minimizaron la p谷rdida de tensi車n de las barras. Adem芍s, no se observaron evidencias de fluencia termo-higromec芍nica ni relajaci車n de la tensi車n de las muestras de puentes tensados en este estudio. Wood material has a thermo-hygromechanical behaviour because its deformation depends on the combined action of temperature, relative humidity and mechanical load variations. Stress-laminated timber bridge deck show a reduction of stress in the tension bars mainly due to the relaxation and shrinkage of wood, increasing with moisture content and temperature changes within the wood. The aim of this research was to study the rheological behavior of stress-laminated timber bridge deck samples under temperature and relative humidity variations. A total of 16 samples were previously treated with four types of preservative treatments, which were subjected to four cycles of temperature and relative humidity in a climate chamber. Wood samples deformation and stress in the steel bars were measured. The results showed a significant stress reduction in the steel bar during the summer season and a significant increase during the winter season. The results also showed significant differences between the deformations of control samples compared to the preservative treated samples for each cycle. However, for interlaminar stress, differences were significant only in the winter season. Moreover, for both deformation and interlaminar stress, no significant differences between cycles three and four were found. Therefore there is no evidence of thermo-hygromec
%K Puentes tensados
%K tensi車n en las barras
%K tratamientos de preservaci車n
%K Pinus radiata D.Don
%K Stress-laminated timber bridge deck
%K bar stress
%K preservation treatments
%K Pinus radiata D.Don
%U http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-221X2012000300005