This title slide, labeled "Cover," presents the main topic: "Research on Size Effect of Compressive Strength in Small Cylindrical Ultra-High Performance Concrete Specimens and Numerical Simulation." The subtitle section is for a scientific research report, with placeholders for author, institution, and date.

超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究

科研汇报 作者： 单位： 日期：

Source: 封面主标题：超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究。副标题：科研汇报。包含作者、单位、日期。蓝白渐变背景，简洁科技风。（保留原图）

This agenda slide, titled "目录" (Table of Contents), outlines the presentation structure. It includes five main sections: research background and objectives, experimental design, numerical simulation, size effect analysis, and conclusions with outlook.

目录

1. 1. 研究背景与目标
2. 2. 实验设计
3. 3. 数值模拟
4. 4. 尺寸效应分析
5. 5. 结论与展望

Source: 超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究

This section header slide introduces Section 1 on the research background and objectives. It covers UHPC applications, size effect challenges, and aims to investigate size effects on compressive strength of small cylindrical specimens via numerical simulation.

超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究

1

研究背景与目标

超高性能混凝土（UHPC）应用与尺寸效应问题介绍。目标：探讨小圆柱体抗压强度尺寸效应及数值模拟

Source: 用户提供章节过渡页描述

UHPC features high strength and low brittleness, but size effects impact structural design. This study fills the research gap in small cylinder data to guide engineering applications.

研究背景

• UHPC高强度、低脆性特点
• 尺寸效应影响结构设计
• 研究空白：小圆柱体数据不足
• 本研究指导工程应用

The slide, titled "研究目标" (Research Objectives), lists key goals for the study. These include experimentally measuring compressive strength of small cylinders of different sizes, building a numerical simulation model, analyzing size effect patterns, and proposing design suggestions.

研究目标

• 实验测定不同尺寸小圆柱体抗压强度
• 建立数值模拟模型
• 分析尺寸效应规律
• 提出设计建议

This slide serves as the header for Section 2: Experimental Design. It introduces specimen preparation, size specifications, and loading methods.

2. 实验设计

2

实验设计

试件制备、尺寸规格与加载方式介绍

Source: 原实验图表，蓝白配色

The slide's left column specifies specimen dimensions, such as φ20mm×40mm and φ30mm×60mm small cylinders, made from ultra-high performance concrete with precise ratios of cement, silica fume, sand, and water for strength consistency. The right column outlines loading via universal testing machine in displacement control mode, retaining and optimizing the loading curve graph in blue-white tech style for enhanced academic visuals.

试件规格与加载

The slide displays experimental compressive strengths: 150 MPa for 20mm-diameter cylinders (minimum size) and 120 MPa for 40mm-diameter cylinders (maximum size). It notes a 20% strength drop due to size effects as dimensions increase.

实验结果统计

• 150 MPa: 最小尺寸抗压强度

直径20mm圆柱体

• 120 MPa: 最大尺寸抗压强度

直径40mm圆柱体

• 20%: 尺寸效应强度降幅

随尺寸增大明显下降 Source: 实验数据

This slide is a section header for Section 3, titled "Numerical Simulation." It highlights the use of ABAQUS finite element software with a damage plasticity model.

数值模拟

3

数值模拟

采用ABAQUS有限元软件，损伤塑性模型

Source: 超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究

This slide, titled "Simulation Model and Mesh," illustrates the construction of a small cylinder's 3D model. It highlights optimized fine mesh division and a schematic for boundary condition loading.

模拟模型与网格

!Image

• 小圆柱体三维模型构建
• 精细网格划分优化
• 边界条件加载示意

Source: Wikipedia

The slide outlines a five-step timeline for simulating ultra-high performance concrete (UHPC) small cylinder behavior, starting with finite element model establishment, meshing, axial loading, failure analysis, and peak strength extraction. Results validation shows simulated strength-size curves closely matching experimental data, confirming model accuracy.

模拟过程与结果

步骤1: 模型建立 建立超高性能混凝土小圆柱体有限元模型，定义材料属性和边界条件。 步骤2: 网格划分 生成高质量结构化网格，确保模拟计算精度和收敛性。 步骤3: 加载过程 施加轴向压缩载荷，模拟实验加载条件和速率。 步骤4: 破坏模拟 分析破坏过程，提取峰值强度数据。 步骤5: 结果验证 强度随尺寸变化曲线与实验结果高度匹配，验证模型准确性。

This slide is a section header titled "4. Size Effect Analysis." Its subtitle summarizes the consistency between experiments and simulations while proposing laws of size effects.

4. 尺寸效应分析

4

尺寸效应分析

总结实验与模拟一致性，提出尺寸效应规律

Source: 《超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究》PPT

This slide on "Size Effect Law" presents the formula σ = k / D^m, fitted to experimental data via a logarithmic strength-size curve. The model achieves low fitting error (<5%) and high goodness-of-fit (R² = 0.98).

尺寸效应规律

• <5%: 拟合误差

强度-尺寸对数曲线

• σ = k / D^m: 尺寸效应公式

实验数据拟合模型

• R² = 0.98: 拟合优度

对数曲线精度高

The slide discusses the size effect mechanism, emphasizing the significant influence of the interface transition zone, and validates the accuracy of numerical simulations. It offers engineering suggestions, including a strength reduction factor for small components and optimizing reinforcement spacing to mitigate size effects.

讨论与建议

• 尺寸效应机理：界面过渡区显著影响
• 数值模拟精度得到有效验证
• 工程建议：小构件强度折减系数
• 优化配筋间距以降低尺寸效应

The conclusion slide confirms significant size effects in small cylinders, validates the numerical model's reliability, and proposes future multi-scale simulations. It closes with "Thank you for listening! Q&A."

结论

• 证实小圆柱体尺寸效应显著

• 数值模型可靠
• 未来：多尺度模拟

感谢聆听！Q&A

Source: 超高性能混凝土小圆柱体抗压强度尺寸效应及数值模拟研究