Clarification on the Spalling of Concrete Exposed to Fire

关于混凝土遇火剥落的澄清

• 批准号: 17560406
• 负责人: MORIMOTO Hiroaki
• 金额: $ 2.24万
• 依托单位: Gifu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17560406/
• 关键词: Concrete; Spalling; Fire; Vapor pressure; Thermal stress; Acoustic emission; 湿度応力

The influences of strength and water content on the spalling of concrete exposed to fire were examined by the experiments, in which vapor pressure, temperature, and AE(Acoustic Emission)arising from cracking were measured. The results obtained by the study are as follows ;1. Vapor pressures of more than 2.2Mpa were measured in the spalling concrete specimens.2. Before the spallins arose, the thermal cracking were observed. The thermal cracks is assumed to have a large influence on the scale of subsequent spalling.3. The spalling with the wet specimens expands from surface toward inside being accompanied by fairly local apalling, meanwhile with the air-dried specimens arises in a region adjacent to the surface at a stretch. This is believed linked to the moisture distribution in the specimens.4. The spalling is assumed to develop due to chain reaction of cracking, explosion of vapor pressure, spalling, redistribution of vapor pressure, re-explosion, re-spalling.5. Measuring of AE can be applied for estimating of the development of the cracking and the spalling.6. AE arose over the whole area of the surface of specimens after 20 to 30 minutes after the beginning of application of heat. More AE counts were measured with the high strength concrete specimens as compared to the normal strength concrete specimens. No meaningful differences in AE counts were observed between the wet specimens and the air-dried specimens.

通过实验，测量了蒸汽压、温度和开裂产生的声发射，研究了强度和含水量对混凝土火灾剥落的影响。研究所得结果如下： 1．剥落混凝土试件的蒸汽压大于2.2Mpa。 2．在剥落出现之前，观察到热裂纹。假设热裂纹对后续剥落的规模有很大影响。3．湿样本的剥落从表面向内部扩展，并伴有相当局部的令人震惊的现象，而风干样本的剥落则在邻近表面的区域突然出现。这被认为与样本中的水分分布有关。4．假定剥落是由于裂化、蒸气压爆炸、剥落、蒸气压重新分布、再爆炸、再剥落的链式反应而发生的。5． AE的测量可用于估计裂纹和剥落的发展情况。6．开始加热后 20 至 30 分钟后，样品表面的整个区域都会出现 AE。与普通强度混凝土样本相比，高强度混凝土样本测量到更多的 AE 计数。在湿样本和风干样本之间没有观察到 AE 计数的有意义的差异。

项目成果

高温加熱によるコンクリートの爆裂現象に関する実験的研究

混凝土高温加热爆炸现象试验研究

• 发表时间: 2007
• 期刊: コンクリート工学年次論文集 29(印刷中)
• 作者: R. Enomoto;Y. Izue;Y. Yamashita;T. Ono;A. Kumamoto;Y. Kasahara;後藤 由貴;T. Ono;A. Kumamoto;Y. Goto;Y. Kasahara;T. Ono;Y. Miyoshi;Y. Miyoshi;Y. Miyoshi;長野 勇;井町 智彦;後藤 由貴;B. Tsurutani;K. Shiokawa;H. Matsumoto;I. Nagano;T. Imachi;Y. Goto;B. Tsurutani;K. Shiokava;B.Tsurutani;K.Shiokawa;越山 祐一;中嶋 充;長野 勇;Y.Kasahara;Y.Kasahara;Y.Goto;Y.Goto;R.Higashi;Y. Kasahara;Y. kasahara;Y. Kasahara;Y. Goto;Y. Goto;Y. Goto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;Y. Kasahara;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;王若平;小澤満津雄;R.Wang;M.Ozawa;小澤満津雄
• 通讯作者: 小澤満津雄

Experimental study on the spalling of concrete

混凝土剥落试验研究

• 发表时间: 2006
• 期刊: Annual journal of concrete engineering 28-1
• 作者: R. Enomoto;Y. Izue;Y. Yamashita;T. Ono;A. Kumamoto;Y. Kasahara;後藤 由貴;T. Ono;A. Kumamoto;Y. Goto;Y. Kasahara;T. Ono;Y. Miyoshi;Y. Miyoshi;Y. Miyoshi;長野 勇;井町 智彦;後藤 由貴;B. Tsurutani;K. Shiokawa;H. Matsumoto;I. Nagano;T. Imachi;Y. Goto;B. Tsurutani;K. Shiokava;B.Tsurutani;K.Shiokawa;越山 祐一;中嶋 充;長野 勇;Y.Kasahara;Y.Kasahara;Y.Goto;Y.Goto;R.Higashi;Y. Kasahara;Y. kasahara;Y. Kasahara;Y. Goto;Y. Goto;Y. Goto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;Y. Kasahara;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;王若平;小澤満津雄;R.Wang;M.Ozawa;小澤満津雄;王若平;川上寛正;M.Ozawa;R.Wang
• 通讯作者: R.Wang

若材齢コンクリートの熱膨張係数推定法の関する研究

新拌混凝土热膨胀系数估算方法研究

• 发表时间: 2005
• 期刊: セメント・コンクリート論文集 59
• 作者: R. Enomoto;Y. Izue;Y. Yamashita;T. Ono;A. Kumamoto;Y. Kasahara;後藤 由貴;T. Ono;A. Kumamoto;Y. Goto;Y. Kasahara;T. Ono;Y. Miyoshi;Y. Miyoshi;Y. Miyoshi;長野 勇;井町 智彦;後藤 由貴;B. Tsurutani;K. Shiokawa;H. Matsumoto;I. Nagano;T. Imachi;Y. Goto;B. Tsurutani;K. Shiokava;B.Tsurutani;K.Shiokawa;越山 祐一;中嶋 充;長野 勇;Y.Kasahara;Y.Kasahara;Y.Goto;Y.Goto;R.Higashi;Y. Kasahara;Y. kasahara;Y. Kasahara;Y. Goto;Y. Goto;Y. Goto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;Y. Kasahara;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;王若平;小澤満津雄;R.Wang;M.Ozawa;小澤満津雄;王若平;川上寛正;M.Ozawa;R.Wang;H.Kawakami;王若平;MITSUO.OZAWA;王若平;M.Ozawa;小澤満津雄
• 通讯作者: 小澤満津雄

高温加熱よるコンクリートの爆裂現象メカニズムに関する研究

高温加热引发混凝土爆炸机理研究

• 发表时间: 2007
• 期刊: 平成18年度土木学会中部支部研究発表会講演概要集
• 作者: R. Enomoto;Y. Izue;Y. Yamashita;T. Ono;A. Kumamoto;Y. Kasahara;後藤 由貴;T. Ono;A. Kumamoto;Y. Goto;Y. Kasahara;T. Ono;Y. Miyoshi;Y. Miyoshi;Y. Miyoshi;長野 勇;井町 智彦;後藤 由貴;B. Tsurutani;K. Shiokawa;H. Matsumoto;I. Nagano;T. Imachi;Y. Goto;B. Tsurutani;K. Shiokava;B.Tsurutani;K.Shiokawa;越山 祐一;中嶋 充;長野 勇;Y.Kasahara;Y.Kasahara;Y.Goto;Y.Goto;R.Higashi;Y. Kasahara;Y. kasahara;Y. Kasahara;Y. Goto;Y. Goto;Y. Goto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;Y. Kasahara;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;王若平
• 通讯作者: 王若平

A Study on the Method of Estimating Creep of Early-age Concrete

早龄混凝土徐变估算方法的研究

• 发表时间: 2005
• 期刊: Creep, Shrinkage and Durability of Concrete and Concrete Structures, CONCREEP8 8
• 作者: R. Enomoto;Y. Izue;Y. Yamashita;T. Ono;A. Kumamoto;Y. Kasahara;後藤 由貴;T. Ono;A. Kumamoto;Y. Goto;Y. Kasahara;T. Ono;Y. Miyoshi;Y. Miyoshi;Y. Miyoshi;長野 勇;井町 智彦;後藤 由貴;B. Tsurutani;K. Shiokawa;H. Matsumoto;I. Nagano;T. Imachi;Y. Goto;B. Tsurutani;K. Shiokava;B.Tsurutani;K.Shiokawa;越山 祐一;中嶋 充;長野 勇;Y.Kasahara;Y.Kasahara;Y.Goto;Y.Goto;R.Higashi;Y. Kasahara;Y. kasahara;Y. Kasahara;Y. Goto;Y. Goto;Y. Goto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;A. Kumamoto;Y. Kasahara;Y. Kasahara;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;S. Yamawaki;T. Ito;M. Nakashima;Y. Sakai;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;Y. Goto;Y. Kasahara;Y. Kasahara;Y. Goto;R. Higashi;王若平;小澤満津雄;R.Wang;M.Ozawa;小澤満津雄;王若平;川上寛正;M.Ozawa;R.Wang;H.Kawakami;王若平;MITSUO.OZAWA;王若平;M.Ozawa
• 通讯作者: M.Ozawa