- 摘 要
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(蘭州理工大學(xué)土木工程學(xué)院，蘭州 730050)
［摘要］對25個結(jié)構(gòu)鋼V形缺口板試件進(jìn)行斷裂試驗。試驗表明：裂紋起始于受三軸強(qiáng)約束的V形缺口厚度心部，隨后沿厚度方向擴(kuò)展，裂紋貫通后迅速沿寬度發(fā)展，宏觀裂紋大致垂直于載荷方向，單缺口試件斷裂延性略高于雙缺口試件，薄板斷裂延性明顯高于厚板。斷口呈暗灰色，斷口大量韌窩顯示出明顯的剪切斷裂痕跡，斷裂類型為正斷和剪斷混合型斷裂，顯示了斷裂的定性規(guī)律。從整體上看，試驗數(shù)據(jù)離散性較小，為研究結(jié)構(gòu)鋼斷裂機(jī)理及抗斷理論提供了可靠的試驗依據(jù)。
［關(guān)鍵詞］結(jié)構(gòu)鋼；斷裂機(jī)理；缺口板；初始裂紋
Fracture experiments of structural steel V-shaped notched plates
Wang Wanzhen, Su Renquan, Du Yongfeng, Li Song(School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China)
Abstract:In order to study rupture mechanism and fracture design of structural steel, fracture experiments were performed on 25 notched plates. The results indicate that the first crack initiated at the center of notched section which had strong stress triaxiality and expanded towards two sides along the thickness of the plates. The crack is vertical to the direction of load and fracture quickly, the ductility of single-notched plates is higher than those of double-notched ones, and the ductility of thin plates is also higher than those of thick ones. Fracture section is dark gray and has many holes at the center,where the trace of shearing fracture is obviously. Fracture mode is combination of shear and normal fracture and reveals fracture rules. Generally, the data of the experiments are stability and qualitatively reveal fracture rules. Experimental results supply objective evidence to investigate rupture mechanism and fracture design theory of structural steel.
Keywords:structural steel; rupture mechanism; notched plates; initial crack
*國家自然科學(xué)基金(50808098)和甘肅省教育廳科研基金(0603-09)。
作者簡介：王萬禎，博士，副教授，Email：wangwanzhen1975@sina.com。
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