[1]张大山,张建春,董毓利,等.火灾下钢-混凝土组合楼盖的声发射特性[J].长安大学学报(自然科学版),2018,38(06):69-78.
 ZHANG Da shan,ZHANG Jian chun,DONG Yu li,et al.Acoustic emission characteristic of steelconcretecomposite floor during fire[J].Journal of Chang’an University (Natural Science Edition),2018,38(06):69-78.
点击复制

火灾下钢-混凝土组合楼盖的声发射特性()
分享到:

长安大学学报(自然科学版)[ISSN:1006-6977/CN:61-1281/TN]

卷:
第38卷
期数:
2018年06期
页码:
69-78
栏目:
桥梁与隧道工程
出版日期:
2018-12-01

文章信息/Info

Title:
Acoustic emission characteristic of steelconcretecomposite floor during fire
作者:
张大山张建春董毓利卢鑫
(华侨大学 土木工程学院,福建 厦门 361021)
Author(s):
ZHANG Dashan ZHANG Jianchun DONG Yuli LU Xin
(College of Civil Engineering, Huaqiao University, Xiamen 361021, Fujian, China)
关键词:
结构工程声发射监测钢混凝土组合楼盖火灾
Keywords:
structural engineering acoustic emission monitoring steelconcrete composite floor fire
文献标志码:
A
摘要:
为研究火灾下钢混凝土组合楼盖的声发射特性,利用声发射采集仪对火灾下长跨跨中布置次梁的足尺钢混凝土组合楼盖进行监测。火灾模拟环境为ISO 834标准升温曲线,通过对钢混凝土组合楼盖的板角、周边、跨中等关键位置处的声发射数据进行滤波分析,研究典型的声发射特征参数(计数、累计计数、幅值和能量),并结合试验破坏的宏观现象,探讨了火灾下钢混凝土组合楼盖的传力机理及与声发射参数特征的关联。研究结果表明:火灾作用下钢混凝土组合楼盖的声发射参数随截面温度的非线性变化表现出不同的特征,且与混凝土板面上裂缝开展的不同阶段相吻合,这与材料和结构的力学行为密切相关;试验过程中,声发射源信号在升温初期最为活跃,这与声发射信号中计数(振铃)和累计计数曲线的转折点特征吻合,可以用来反映裂缝开展的过程、分布区域和密集程度;声发射事件在空间位置上的分布特征变化是结构失稳和内部损伤产生的重要前兆,声发射信号本身的强弱(幅值、能量等参数)需特别关注;降温时,组合结构中钢梁、混凝土板间热膨胀系数的差异使得两者之间会有错动产生,直接导致该阶段的声发射信号仍然较为活跃,建议今后建立火灾下结构倒塌的声发射预警系统时予以关注。
Abstract:
To study the acoustic emission (AE) characteristics of a steelconcrete composite floor during a fire, a MicroⅡ multichannel digital AE instrument was used to conduct AE nondestructive monitoring during a fire on a fullscale composite floor,which had a secondary frame beam arranged along the short spans in the middle of long spans. The simulated fire environment was based on the ISO 834 international standard curve. AE signal data of measuring points were collected for filtering analysis at critical locations,such as the positions of corner, perimeter, and midspan in the composite floor. Through analyzing typical AE characteristic parameters, such as ringing count, cumulative count, amplitude, and energy, and combining them with the experimental phenomena during the tests, the loadtransferring mechanism and damage process in the composite floor during fire were examined. The results show that the AE parameters of a steelconcrete composite floor during a fire show different characteristics as the temperature along the slab depth changes nonlinearly, and the characteristics are in accordance with the crack stages of the slab. The phenomenon is considered to be caused by the mechanical behaviors of the material and structures. During the tests, the signal of the AE sources at early stage is most active, and it is in accordance with the inflection points in the curve of the ringing count and cumulative count with time and also the progress, distributed area, and intensity of the cracks on the slab surface. The variation of distribution characteristics for AE events in space is an important indicator of structural instability and inner damage, and its intensity (amplitude, energy, etc.) should receive more attention. During the cooling period, a certain amount of movement appeared between the steel beam and concrete slabs because of the difference coefficient of thermal expansion. Accordingly, the AE signal is still active at this stage. For this reason, AE characteristics during the cooling period should be considered sufficiently when a collapse warning system for building structures during fires is developed. 7 figs, 25 refs.

相似文献/References:

[1]李新忠,魏雪英,赵均海.混凝土力学性能的应变率效应[J].长安大学学报(自然科学版),2012,32(02):82.
 LI Xin-zhong,WEI Xue-ying,ZHAO Jun-hai.Strain rate effect on mechanical properties of concrete[J].Journal of Chang’an University (Natural Science Edition),2012,32(06):82.
[2]王春玲,王爱勤,吴艳红.弹性半空间地基上正交异性矩形中厚板的弯曲[J].长安大学学报(自然科学版),2012,32(02):87.
 WANG Chun-ling,WANG Ai-qin,WU Yan-hong.Bending of orthotropic rectangular middle thick plate on elastic half-space foundation[J].Journal of Chang’an University (Natural Science Edition),2012,32(06):87.
[3]杨富社,徐春龙,王晋国.基于地震响应时程的多层轻钢结构特性[J].长安大学学报(自然科学版),2012,32(04):55.
 YANG Fu-she,XU Chun-long,WANG Jin-guo.Structural property of multi-layer lightweight steel based on seismic response time history[J].Journal of Chang’an University (Natural Science Edition),2012,32(06):55.
[4]苟长飞,叶 飞,张金龙.城市地下空间需求预测及其分布体系建立[J].长安大学学报(自然科学版),2012,32(05):58.
 GOU Chang-fei,YE Fei,ZHANG Jin-long.Demand forecasting and demand distributional system development method of urban underground space[J].Journal of Chang’an University (Natural Science Edition),2012,32(06):58.
[5]刘 鸣,刘伯权.钢筋混凝土柱低周疲劳力学性能分析[J].长安大学学报(自然科学版),2012,32(05):65.
 LIU Ming,LIU Bo-quan.Low-cycle fatigue damage for shear behavior of reinforced concrete columns[J].Journal of Chang’an University (Natural Science Edition),2012,32(06):65.
[6]万战胜,夏永旭,韩瑞昌.化学锚栓的高温力学性能试验[J].长安大学学报(自然科学版),2010,30(01):63.
 WAN Zhan-sheng,XIA Yong-xu,HAN Rui-chang.Experimental research on mechanic behavior under high temperature of chemistry anchor bolts[J].Journal of Chang’an University (Natural Science Edition),2010,30(06):63.
[7]张志权,赵均海,张玉芬,等.复合钢管混凝土柱轴压承载力的计算[J].长安大学学报(自然科学版),2010,30(01):67.
 ZHANG Zhi-quan,ZHAO Jun-hai,ZHANG Yu- fen,et al.Axial bearing capacity of composite concrete-filled steel tubular columns[J].Journal of Chang’an University (Natural Science Edition),2010,30(06):67.
[8]丁江澍,刘伯权,冼耀强.空间错位双排密贴PHC桩支护结构分析[J].长安大学学报(自然科学版),2010,30(04):66.
 DING Jiang-shu,LIU Bo-quan,XIAN Yao-qiang.Analysis of retaining structure with space double-row layout dislocation PHC piles[J].Journal of Chang’an University (Natural Science Edition),2010,30(06):66.
[9]陈 峰,郑建岚.自密实混凝土与老混凝土的粘结-滑移性能[J].长安大学学报(自然科学版),2010,30(06):56.
 CHEN Feng,ZHENG Jian-lan.Bond-slip relationship between self-compacting concrete and old concrete[J].Journal of Chang’an University (Natural Science Edition),2010,30(06):56.
[10]李炳宏,江世永,飞 渭.基于挠度控制方法的BFRP筋混凝土梁抗弯设计[J].长安大学学报(自然科学版),2010,30(06):61.
 LI Bing-hong,JIANG Shi-yong,FEI Wei.Flexural design of concrete beams reinforced with BFRP bars based on deflection control approach[J].Journal of Chang’an University (Natural Science Edition),2010,30(06):61.

更新日期/Last Update: 2018-12-18