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（1 東南大學(xué)土木工程學(xué)院， 南京 210096； 2 南京市金陵中學(xué)， 南京 210005）

［摘要］通過(guò)4組14根膠合木短柱四面受火后力學(xué)性能的對(duì)比試驗(yàn)，研究不同截面尺寸、表面處理、受火時(shí)間后膠合木柱的剩余承載力、破壞形態(tài)和炭化速度的變化規(guī)律。研究表明，四面受火20～60min后，膠合木柱剩余承載力隨受火時(shí)間增加而顯著降低，下降幅度為21%～73%，且下降幅度隨截面尺寸的增加而減小，截面尺寸為200×200時(shí)，下降幅度為28%～73%，截面尺寸為300×300時(shí)，下降幅度為21%～51%。膠合木柱炭化速度隨受火時(shí)間增加有所降低。提出的基于實(shí)測(cè)炭化速度剩余承載力改進(jìn)計(jì)算方法的計(jì)算結(jié)果與試驗(yàn)結(jié)果吻合較好，可用于預(yù)測(cè)四面受火膠合木柱的剩余承載力。

［關(guān)鍵詞］膠合木柱； 四面受火； 力學(xué)性能； 炭化速度； 阻燃涂料

中圖分類號(hào)：TU317-1文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2018)10-0068-05

Experimental research on the mechanical behavior of short glulam columns with different fire retardant coating exposed to four-side fire

Hu Xiaofeng1, Han Yichen2

(1 School of Civil Engineering, Southeast University, Nanjing 210096, China; 2 Nanjing Jinling High School, Nanjing 210005, China)

Abstract:The residual bearing capacity, failure mode and charring rare of 14 glulam columns in 4 series exposed to four\|side fire were experimentally studied under different cross-sections, fire retardant coating and exposed time. It is found that the residual bearing capacity of exposed specimens decrease obviously while the exposed time increasing, the residual bearing capacity decreases by 21% to 73% while the exposed time increased from 20 minutes to 60 minutes. The residual bearing capacity for specimens with 200×200 cross-section decreased by 28% to 73%, while for 300×300 cross-section was 21% to 51%. The charring rate decreases with increasing exposed time. The modified calculated method for the residual bearing capacity of glulam columns based on testing charring rate agrees well with the test results, which can be used for calculating the residual bearing capacity of glulam columns.

Keywords:glulam column; exposure to four-side fire; mechanical behavior; charring rate; fire retardant coating

*上海市青年科技啟明星計(jì)劃項(xiàng)目（17QB1403400），上海市科委課題（17DZ1203702）。

作者簡(jiǎn)介：胡小峰，碩士，Email：702236754@qq.com。