size Effect on compressive Behavior of Plain and Confined Concrete

尺寸对普通混凝土和受限混凝土压缩性能的影响

• 批准号: 07650676
• 负责人: KOIKE Sachio
• 金额: $ 0.96万
• 依托单位: Aichi Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650676/
• 关键词: Size Effect; Compressive Strangth; Plastic Deformation Behavior; Strain Softning; Confined Concrete; Stress-Strain Curve; Ductility; Lateral Reinforcement; 横拘束力; 応力下降域; 靱性

In the present study, following four studies were carried out to examined the size effect on the compressive behavior of concrete prism under uniaxial compression..1)In the present study, the effects of the specimen size and aggregate size on the inelastic stress-strain behavior of plain and confined concrete were examined. The following statement can be drawn from the study.a)For air cured plain microconcrete in which the size of aggregate is reduced inproportion to the size of a specimen, the compressive strength increased and the descending portion of stress-strain curve showed more brittle behavior with increasing size of specimen or aggregate.b)The compressive strength of confined concrete increased with increasing size of specimen when cured in air. On the other hand, the size effect was almost negligible in water cured specimens. The stress-strain curve of confined concrete showed more brittle behavior with increasing size of specimen and degree of such size effectdepended on th … More e spacing of hoops.2)A series of uniaxial compression tests of confined concretes were carried out to examine the size effects on their compressive behavior. The strength of concrete has been varied from about 300-700 kgf/cm^2 to the ultra-high level of about 1000 kgf/cm^2. Based on the test results, discussion was carried out concerning the effect of specimen size on compressive strength, strain at the peak stress, and stress-strain curves of confined concrete.3)The effects of specimen size on stress-strain behavior of confined concrete and confined micro-concrete prism are examined. Experimental factors include the section size of specimen (bxb, b=9.7,15,20 and 25cm), the pitch of hoops (proportional pitch and fixed pitch), and the type of hoops (rectangular hoop and rectangular hoop with cross type subtie). The maximum sizes of aggregate are 15mm for normal concrete, and 12,9 and 6mm for microconcrete. Following statements can be drawn from the test results.a)For the same lateral reinforcement ratio, size effect on the strength of confined concrete with fixed pitch of hoop (S=1.6cm, rectangular hoop) is smaller than thoseof large specimen with proportional pitch of hoop (S=b/6, S=1.6cm for b=9.7cm), but the size effect on the stress-strain behavior is still rather remarkable.b)The Size effect of stress-strain curves of confined microconcrete are observed, as well as that of normal concrete.4)The comprete formulas of stress-strain curves of the confined concrete considering specimen sizes are proposed. These formulas considerthe experimental factors including the section size of specimen, the pitch of hoops (proportional pitch), concrete strength and yield strength of hoops. The results from the formulas agree well with the test results. Less

本文通过以下四个方面研究了混凝土棱柱体单轴受压性能的尺寸效应。1）研究了试件尺寸和骨料尺寸对素混凝土和约束混凝土非弹性应力-应变行为的影响。研究结果表明：（1）对于骨料尺寸与试件尺寸不成比例减小的气养素微混凝土，随着试件尺寸或骨料尺寸的增大，其抗压强度增大，应力-应变曲线的下降段表现出更强的脆性;（B）气养约束混凝土的抗压强度随试件尺寸的增大而增大。另一方面，在水固化试样中，尺寸效应几乎可以忽略不计。随着试件尺寸的增大，约束混凝土的应力-应变曲线表现出更强的脆性，且这种尺寸效应的程度取决于试件的强度 ...更多信息 通过单轴压缩试验研究了约束混凝土的尺寸效应。混凝土的强度从约300-700 kgf/cm ^2变化到约1000 kgf/cm ^2的超高水平。根据试验结果，讨论了试件尺寸对约束混凝土抗压强度、峰值应力应变和应力-应变曲线的影响。3）研究了试件尺寸对约束混凝土和约束微混凝土棱柱体应力-应变特性的影响。试验因素包括试件截面尺寸（b × B，B= 9.7，15，20和25 cm），箍的节距（等节距和定节距），箍的类型（矩形箍和十字形箍）。普通混凝土的最大骨料粒径为15 mm，微混凝土的最大骨料粒径为12 mm、9mm和6 mm。试验结果表明：（1）在相同的侧筋率下，箍筋间距一定时，约束混凝土强度的尺寸效应（S=1.6cm，矩形箍筋）比等间距箍筋的大试件小（S=B/6，S=1.6cm，B=9.7cm），但尺寸效应对应力-应变行为的影响仍相当显著。B）观察到约束微混凝土应力-应变曲线的尺寸效应。4）提出了考虑试件尺寸的约束混凝土应力-应变全曲线拟合公式。这些公式考虑了试件截面尺寸、箍筋间距（比例间距）、混凝土强度和箍筋屈服强度等试验因素。计算结果与试验结果吻合较好。少

项目成果

S.Koike, et al.: "Formulas of Stress-Strain Curves of Confined Concrete Considering Specimen Size" Proceedings of the Annual Meeting of AIJ.(Kinki). C-2. 799-800 (1997)

S.Koike 等人：“考虑样本尺寸的受限混凝土应力-应变曲线公式”AIJ 年会论文集。（近畿）。

小池 狭千朗(幸男): "プレーンおよびコンファインドコンクリートの圧縮特性の寸法効果に関する実験的研究" 愛知工業大学研究報告. 31号B. 137-148 (1996)

小池幸郎（Yukio）：“普通混凝土和复合混凝土压缩性能的尺寸效应的实验研究”爱知工业大学研究报告第 31 B. 137-148（1996 年）。

大澤 潤: "コンファインドコンクリートの寸法効果に及ぼす帯筋間隔と骨材寸法の影響(その2 実験結果と考察)" 日本建築学会大会学術講演梗概集(近畿). 大会号 C-2. 481-482 (1996)

Jun Osawa：“箍筋间距和骨料尺寸对约束混凝土尺寸效应的影响（第 2 部分：实验结果和讨论）”日本建筑学会会议（近畿）学术讲座摘要 C-2。 481- 482 (1996)

S.Koike et al.: "Size Effect on Compressive vihavior of Plain and Confained Concrete" Bulletin of Aichi Institute of Technology. No.31, B. (1996)

S.Koike 等人：“尺寸对普通混凝土和封闭混凝土压缩行为的影响”爱知工业大学通报。

S.Koike, et al.: "Effect of Size and Slenderness Ratio of Specimen on Stress-Strain Curves of Confined Concrete" Proceedings of the Japan Concrete Institute. Vol.12, No.2. 833-838 (1996)

S.Koike 等人：“试件尺寸和长细比对受限混凝土应力应变曲线的影响”日本混凝土学会会议录。