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(1 上海市工程結(jié)構(gòu)新技術(shù)重點(diǎn)實(shí)驗(yàn)室，上海 200032； 2 上海市建筑科學(xué)研究院，上海 200032； 3 東南大學(xué)，南京 210096)

［摘要］通過6根四面受火木柱耐火極限的對比試驗(yàn)，研究不同持荷水平、是否采用石灰膏抹面對木柱耐火極限的影響。研究結(jié)果表明，四面受火木柱耐火極限隨著荷載水平的增加而明顯降低。采用石灰膏抹面后，其耐火極限有所增加。石灰膏抹面能有效降低四面受火木柱內(nèi)的溫升梯度，延緩木柱開始炭化的時(shí)間，降低炭化速度。

［關(guān)鍵詞］木柱；四面受火；石灰膏抹面；耐火極限

Experimental research on fire endurance of timber columns exposed to four-side fire

Li Xiangmin^1,2, Li Shuaixi³, Xu Qingfeng^1,2, Xu Qiang², Zhang Jin³, Mu Baogang³(1 Shanghai Key Laboratory of New Technology Research on Engineering Structure, Shanghai 200032, China; 2 Shanghai Research Institute of Building Sciences, Shanghai 200032, China; 3 Southeast University, Nanjing 210096, China)

Abstract:To learn the effective factors such as load level and lime putty finishing, six timber columns were tested. It was found that the fire endurance of timber column exposed to four-side fire obvious decreases when the load level increases. The fire endurance will extend after lime putty finishing is used. The lime putty finishing will obviously drop the increase gradient of temperature inside the timber column, effectively delay the beginning time of charring and reduce the charring rate.

Keywords:timber column; exposed to four-side fire; lime putty finishing; fire endurance

*上海市科委青年科技啟明星計(jì)劃(07QB14031)和國家科技支撐計(jì)劃(2006BAJ03A10 02)。

作者簡介：李向民，博士，高級工程師，Email:lxm-sh@tom.com。

 參考文獻(xiàn)

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［8］許清風(fēng)，徐強(qiáng)，李向民，等. 基于炭化速度的木結(jié)構(gòu)防火設(shè)計(jì)方法研究［R］. 上海市建筑科學(xué)研究院，2009.