- 摘 要
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（1 上海市建筑科學(xué)研究院 上海市工程結(jié)構(gòu)安全重點實驗室， 上海 200032；2 東南大學(xué)建筑設(shè)計研究院有限公司， 南京 210096； 3 東南大學(xué)土木工程學(xué)院， 南京 210096）
［摘要］通過4組18根膠合木梁三面受火耐火極限的對比試驗，研究截面尺寸、持荷比、阻燃涂料、木梁跨中受拉區(qū)是否存在指接對耐火極限的影響。研究結(jié)果表明，隨著持荷比增加，三面受火膠合木梁耐火極限明顯降低，當(dāng)持荷比由30%增加到50%時，耐火極限降低5～29min；隨著截面尺寸增加，耐火極限略有增加，當(dāng)截面尺寸由100×200增加到150×300時，耐火極限增加1～12min；膠合木梁表面采用I型阻燃涂料涂抹后耐火極限提高4～6min，采用Ⅱ型阻燃涂料常溫常壓浸漬后耐火極限提高4～13min；純彎段受拉區(qū)存在指接時，耐火極限降低4～25min。多數(shù)試件豎向炭化速度大于水平炭化速度，有阻燃涂料木梁的炭化速度略小于沒有阻燃涂料木梁的炭化速度。
［關(guān)鍵詞］膠合木梁； 阻燃涂料； 三面受火； 耐火極限； 指接
中圖分類號：TU317-1文獻(xiàn)標(biāo)識碼：A文章編號：1002-848X(2018)10-0073-06
Experimental research on fire endurance of glulam beams with different fire retardant coating exposed to three-side fire
Xu Qingfeng1, Han Chongqing2, Hu Xiaofeng3, Chen Lingzhu1, Leng Yubing1
(1 Shanghai Key Laboratory of Engineering Structure Safety, Shanghai Research Institute of Building Sciences, Shanghai 200032, China; 2 Architects & Engineers Co., Ltd. of Southeast University, Nanjing 210096, China; 3 School of Civil Engineering, Southeast University, Nanjing 210096, China)
Abstract:To learn about the effective factors of fire endurance, such as cross-section, load ratio, fire retardant coating and whether the finger joints existing in the tension zone of wooden beam cross section, 18 specimens in 4 series glulam beams exposed to three-side fire were experimentally studied. It is found that the fire endurance of glulam beams exposed to three-side fire decreased greatly with the increasing load ratio. When the load ratio increases from 30% to 50%, the fire endurance decreases 5～29min; the fire endurance increases slightly with the increasing cross-section. When the cross-section increases from 100×200 to 150×300, the fire endurance increases 1～12min. The fire endurance increases 4～6min when painted the I type fire retardant coating over the beam surfaces; the fire endurance increases 4～13min by Ⅱ type fire retardant coating impregnation under normal pressure and normal temperature. The finger joints at the tension zone reduces the fire endurance about 4～25min. The vertical charring rate of most specimens is greater than the horizontal charring rate, and the charring rate of specimens with fire retardant coating is slightly smaller than the others without fire retardant coating.
Keywords:glulam beam; fire retardant coating; exposed to three-side fire; fire endurance; finger joint
*上海市科委標(biāo)準(zhǔn)項目（17DZ2202600），上海市青年科技啟明星計劃項目（17QB1403400）。
作者簡介：許清風(fēng)，博士，教授級高級工程師，Email：xuqingfeng73@163.com。
