884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

（1 上海市建筑科學(xué)研究院有限公司 上海市工程結(jié)構(gòu)安全重點(diǎn)實(shí)驗(yàn)室， 上海 200032；2 國(guó)際竹藤組織， 北京 100102）

［摘要］紫外線(xiàn)是導(dǎo)致材料老化的主要因素之一，通過(guò)人工加速老化試驗(yàn)，模擬太陽(yáng)光中的紫外線(xiàn)輻射，加上溫濕度循環(huán)變化的影響，測(cè)試未經(jīng)防護(hù)處理的工程竹的物理力學(xué)性能，并與花旗松木材在紫外線(xiàn)輻射下的物理力學(xué)性能變化進(jìn)行對(duì)比，評(píng)價(jià)膠合竹、重組竹、花旗松木材試樣的抗紫外線(xiàn)老化性能。結(jié)果表明，花旗松木材顏色對(duì)紫外線(xiàn)輻射比較敏感，受輻射面有明顯的顏色變深，在紫外線(xiàn)輻射下膠合竹也發(fā)生顏色變黃但沒(méi)有花旗松木材嚴(yán)重，重組竹的顏色變化不明顯； 除順紋抗壓強(qiáng)度膠合竹降幅最大外，順紋抗壓彈性模量、順紋抗拉強(qiáng)度、抗彎強(qiáng)度、抗彎彈性模量均為花旗松木材降幅最大?？傮w來(lái)說(shuō)，重組竹的抗紫外線(xiàn)老化性能最優(yōu)，但膠合竹、重組竹、花旗松木材這三種材料在紫外線(xiàn)輻射作用下均有不同程度的力學(xué)性能退化，用于室外環(huán)境時(shí)需要進(jìn)行防護(hù)處理。

［關(guān)鍵詞］工程竹； 膠合竹； 重組竹； 花旗松木材； 紫外線(xiàn)老化； 加速試驗(yàn)

中圖分類(lèi)號(hào)：TU366-3文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2021)02-0131-04

Experimental study on anti-aging performance of engineered bamboo for structural use under UV radiation

LENG Yubing1, XU Qingfeng1, LIU Kewei2

(1 Shanghai Key Laboratory of Engineering Structure Safety, Shanghai Research Institute of  Building Sciences Co., Ltd., Shanghai 200032, China; 2 International Bamboo and Rattan Organization, Beijing 100102, China)

Abstract:UV radiation is one of the main factors that lead to material aging. Through artificial accelerated aging tests, UV radiation in sunlight was simulated, coupled with the influence of temperature and humidity cycles, to test the physical and mechanical properties of unprotected engineered bamboo. The physical and mechanical properties were compared with those of Douglas fir wood under UV radiation, and the anti-aging performance of laminated bamboo, reconsolidated bamboo and Douglas fir wood samples under UV radiation were evaluated. The results show that the wood color of Douglas fir wood is more sensitive to UV radiation, and the radiation surface has obvious color darkening. The laminated bamboo also has yellow color under UV radiation, but the color change of the reconsolidated bamboo is not as obvious as that of Douglas fir wood. In addition to the greatest reduction in grain compressive strength of laminated bamboo, the greatest reduction in grain compressive modulus, grain tensile strength, flexural strength and flexural elastic modulus of Douglas fir wood was found. In general, the recombination bamboo has the best anti-UV aging performance, but the three materials of laminated bamboo, recombination bamboo and Douglas fir wood all have different degrees of mechanical properties degradation under the action of UV radiation, so they need to be protected when used in the outdoor environment.

Keywords:engineered bamboo; laminated bamboo; reconsolidated bamboo; Douglas fir wood; aging performance under UV radiation; accelerated test

*上海市青年科技啟明星計(jì)劃（19QB1405100）。

作者簡(jiǎn)介：冷予冰，博士，博士后，Email: leng_yb@163.com； 通信作者：許清風(fēng)，博士，教授級(jí)高級(jí)工程師，Email: xuqingfeng73@163.com。