Statistical Evaluation of Material Strength

材料强度统计评价

• 批准号: 06805038
• 负责人: IKEDA Kiyohiro
• 金额: $ 1.22万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06805038/
• 关键词: Bifurcation; Strenght variation; Statistics; Initial imperfections; Stress versus strain curves; Concrete; Sand; Bifurcation modes; 応力〜ひずみ.曲線; 確率論

The statistical strength variation of sand and concrete is investigated through the assemblage of statistical data bank of their compressive strength and the application of the bifurcation theory to the data.For concrete, a series of compression tests are conducted on cylindrical specimens to obtain an ensemble of stress versus strain curves. First gless beads of the size of 0.5mm, 1.0mm, and 2.5mm were used for sggregates to observe the influence of the size. Through the application of the bifurcation theory, it has been noted that bifurcation is predominant when the size is small, whereas fracture is predominant when large. Next the influence of the water cement ratio was investigated by varying its values by 26%, 35%, and 62% to note that bifurcation is predominant when its value is large.For sand, a set of 50 triaxial compression tests were conducted on cylindrical Toyoura sand speciments to obtain an ensemble of stress versus strain curves. Since the present theory is applicable only for the case where the bifurcation mode is unique, the photos and sketches of the specimens were taken during the tests to identify the bifurcation modes, and those curves were categorized in view of these modes. The curves categorized in this manner accurately followed the bifurcation theory ; this assesses the validity of the theory.

通过统计数据库的组合和分叉理论的应用到数据中，研究了沙子和混凝土的统计强度变化。对于具体，在圆柱形标本上进行了一系列压缩测试，以获得一组圆柱样品，以获得一组。应力与应变曲线。首先使用0.5mm，1.0mm和2.5mm的大小的珠子，用于观察大小的影响。通过分叉理论的应用，已经注意到，当大小很小时，分叉是主要的，而骨折则主要是大的。接下来，通过将其值降低26％，35％和62％来研究水水泥比的影响，以指出分叉在其值较大时占主导地位。 Toyoura砂样品获得应力与应变曲线的集合。由于本理论仅适用于分叉模式唯一的情况，因此在测试期间拍摄样品的照片和草图以识别分叉模式，并且根据这些模式进行了分类。以这种方式分类的曲线准确地遵循分叉理论。这评估了该理论的有效性。

项目成果

IKEDA,Kiyohiro: "Statistical theory on strength variation of materials" Journal of Structural Eng. JSCE. Vol.41A. 475-484 (1995)

池田清博：“材料强度变化的统计理论”结构工程杂志。

K.IKEDA・K.MARUYAMA: "Compressive Strength Variation of Concrete Specimens due to Imperfection Sensitivity" Fracture Mechanics of Concrete Structures, Proceedings FRAMCOS-2. 2. 425-434 (1995)

K.IKEDA・K.MARUYAMA：“由于不完美敏感性而导致的混凝土试件的抗压强度变化”，《混凝土结构断裂力学》，论文集 FRAMCOS-2（1995 年）。

池田清宏・室田一雄・丸山久一・柳澤栄司: "材料の強度変動の統計理論" 構造工学論文集. 41A. 475-484 (1995)

Kiyohiro Ikeda、Kazuo Murota、Hisaichi Maruyama 和 Eiji Yanagisawa：“材料强度波动的统计理论”《结构工程学报》41A 475-484 (1995)。

K.IKEDA ・ K.MARUYAMA: "Compressive Strength Variation of Concrete Specimens drre to Imperfection Sensitivity" Fracture Mechanics of Concrete Structures, Proceedings FRAM Cos-2. 2. 425-434 (1995)

K.IKEDA ・ K.MARUYAMA：“混凝土样本的抗压强度变化对缺陷敏感性的影响”混凝土结构断裂力学，论文集 FRAM Cos-2. 425-434 (1995)。

池田清宏,室田一雄,丸山久一,柳澤栄司: "材料の強度変動の統計理論" 構造工学論文集. 41A. (1995)

Kiyohiro Ikeda、Kazuo Murota、Hisaichi Maruyama、Eiji Yanagisawa：“材料强度变化的统计理论”《结构工程学报》41A (1995)。