Dataset of stress distribution in concrete under nonuniform passive confinement

The axial stress distribution of ten FRP-confined concrete columns with different cross-sections is provided in this dataset. The varying cross-sections include a circle, a square with sharp corners, a square with rounded corners, and two rectangles with different aspect ratios. The concrete strength (28-day) is 18.3 MPa, and two different thicknesses of carbon fiber reinforced polymer (CFRP), including 0.111 mm and 0.167 mm, were used to jacket the concrete. All these axial stress distribution data were obtained during a series of concentrically axial compression tests using an “I-Scan" pressure mapping system developed by Tekscan, Inc., Massachusetts, United States (https://www.tekscan.com/).The specimens in this dataset are named as follows:C-A1R1P1 represents a circular specimen with an aspect ratio of 1.0, a corner radius ratio of 1.0 mm, and a CFRP thickness of 0.111 mm.C-A1R1P2 represents a circular specimen with an aspect ratio of 1.0, a corner radius ratio of 1.0 mm, and a CFRP thickness of 0.167 mm.S-A1R0P1 represents a square specimen with an aspect ratio of 1.0, a corner radius ratio of 0.0 mm, and a CFRP thickness of 0.111 mm.S-A1R0P2 represents a square specimen with an aspect ratio of 1.0, a corner radius ratio of 0.0 mm, and a CFRP thickness of 0.167 mm.S-A1R0.4P1 represents a square specimen with an aspect ratio of 1.0, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.111 mm.S-A1R0.4P2 represents a square specimen with an aspect ratio of 1.0, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.167 mm.RT-A1.5R0.4P1 represents a rectangular specimen with an aspect ratio of 1.5, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.111 mm.RT-A1.5R0.4P2 represents a rectangular specimen with an aspect ratio of 1.5, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.167 mm.RT-A2R0.4P1 represents a rectangular specimen with an aspect ratio of 2.0, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.111 mm.RT-A2R0.4P2 represents a rectangular specimen with an aspect ratio of 2.0, a corner radius ratio of 0.4 mm, and a CFRP thickness of 0.167 mm.The dataset contains the following data files:1. “Stress-strain curves.xlsx”, This file comprises the stress-strain curves for the specimens with different cross-sections and CFRP confinement stiffness.2. “Cross-sectional images of cut specimens. rar”, This file contains photographs of cross-sections of cut specimens showing the aggregate and pore distribution at the stress measurement section of the specimens.3. “C-A1R1P1.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined circular specimen (C-A1R1P1).4. “C-A1R1P2.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined circular specimen (C-A1R1P2).5. “S-A1R0P1.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined square specimen with sharp corner (S-A1R0P1).6. “S-A1R0P2.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined square specimen with sharp corner (S-A1R0P2).7. “S-A1R0.4P1.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined square specimen with rounded corner (S-A1R0.4P1).8. “S-A1R0.4P2.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined square specimen with rounded corner (S-A1R0.4P2).9. “RT-A1.5R0.4P1.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined rectangular specimen with an aspect ratio of 1.5 (RT-A1.5R0.4P1).10. “RT-A1.5R0.4P2.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined rectangular specimen with an aspect ratio of 1.5 (RT-A1.5R0.4P2).11. “RT-A2R0.4P1.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined rectangular specimen with an aspect ratio of 2.0 (RT-A2.0R0.4P1).12. “RT-A2R0.4P2.xlsx” Data of axial stress distribution at four characteristic points on the stress-strain curve of FRP confined rectangular specimen with an aspect ratio of 2.0 (RT-A2.0R0.4P2).All data has been analyzed and presented in detail in the following paper:Peng-Da Li, Si-Jie Gao, Yu-Fei Wu. Stress Distribution in Concrete with Nonuniform Passive Confinement.“Axial stress distribution raw data with different axial strain.rar” raw data of stress distribution for all the speciems with different axial strain.“Calibrated axial stress distribution data with different axial strain.rar” Calibrated data of stress distribution for all the speciems with different axial strain. In this dataset, the cross-section was uniformly discretized into a series of elements based on pixel size of pressure mapping sensor. All these elements are in central symmetry, and the four local stresses in the central symmetry elements were grouped together, and the average axial stress of each group was calculated and reassigned to all these four elements. This calibration preserves the global stress distribution characteristics while suppressing non-physical asymmetry and random local fluctuations.

本数据集收录了10根不同截面形式的纤维增强复合材料（FRP, Fiber Reinforced Polymer）约束混凝土柱的轴向应力分布数据。所涉及的变截面形式包括圆形、尖角正方形、圆角正方形，以及两种不同长宽比的矩形。本次试验所用混凝土的28天抗压强度为18.3 MPa，并采用两种厚度的碳纤维增强聚合物（CFRP, Carbon Fiber Reinforced Polymer）对混凝土进行套箍加固，厚度分别为0.111 mm与0.167 mm。所有轴向应力分布数据均通过美国马萨诸塞州Tekscan公司开发的"I-Scan"压力映射系统，在一系列同心轴向压缩试验中测得（https://www.tekscan.com/）。

本数据集内的试样命名规则如下：
C-A1R1P1 代表截面长宽比为1.0、圆角半径比为1.0 mm、CFRP厚度为0.111 mm的圆形试样；
C-A1R1P2 代表截面长宽比为1.0、圆角半径比为1.0 mm、CFRP厚度为0.167 mm的圆形试样；
S-A1R0P1 代表截面长宽比为1.0、圆角半径比为0.0 mm（即尖角）、CFRP厚度为0.111 mm的正方形试样；
S-A1R0P2 代表截面长宽比为1.0、圆角半径比为0.0 mm（即尖角）、CFRP厚度为0.167 mm的正方形试样；
S-A1R0.4P1 代表截面长宽比为1.0、圆角半径比为0.4 mm、CFRP厚度为0.111 mm的正方形试样；
S-A1R0.4P2 代表截面长宽比为1.0、圆角半径比为0.4 mm、CFRP厚度为0.167 mm的正方形试样；
RT-A1.5R0.4P1 代表截面长宽比为1.5、圆角半径比为0.4 mm、CFRP厚度为0.111 mm的矩形试样；
RT-A1.5R0.4P2 代表截面长宽比为1.5、圆角半径比为0.4 mm、CFRP厚度为0.167 mm的矩形试样；
RT-A2R0.4P1 代表截面长宽比为2.0、圆角半径比为0.4 mm、CFRP厚度为0.111 mm的矩形试样；
RT-A2R0.4P2 代表截面长宽比为2.0、圆角半径比为0.4 mm、CFRP厚度为0.167 mm的矩形试样。

本数据集包含以下数据文件：
1. "Stress-strain curves.xlsx"：该文件收录了不同截面形式及CFRP约束刚度的试样的应力-应变曲线。
2. "Cross-sectional images of cut specimens.rar"：该文件包含切割后试样的截面照片，可直观展示试样应力测量截面处的骨料与孔隙分布情况。
3. "C-A1R1P1.xlsx"：FRP约束圆形试样（C-A1R1P1）应力-应变曲线上四个特征点的轴向应力分布数据。
4. "C-A1R1P2.xlsx"：FRP约束圆形试样（C-A1R1P2）应力-应变曲线上四个特征点的轴向应力分布数据。
5. "S-A1R0P1.xlsx"：FRP约束尖角正方形试样（S-A1R0P1）应力-应变曲线上四个特征点的轴向应力分布数据。
6. "S-A1R0P2.xlsx"：FRP约束尖角正方形试样（S-A1R0P2）应力-应变曲线上四个特征点的轴向应力分布数据。
7. "S-A1R0.4P1.xlsx"：FRP约束圆角正方形试样（S-A1R0.4P1）应力-应变曲线上四个特征点的轴向应力分布数据。
8. "S-A1R0.4P2.xlsx"：FRP约束圆角正方形试样（S-A1R0.4P2）应力-应变曲线上四个特征点的轴向应力分布数据。
9. "RT-A1.5R0.4P1.xlsx"：FRP约束长宽比1.5的矩形试样（RT-A1.5R0.4P1）应力-应变曲线上四个特征点的轴向应力分布数据。
10. "RT-A1.5R0.4P2.xlsx"：FRP约束长宽比1.5的矩形试样（RT-A1.5R0.4P2）应力-应变曲线上四个特征点的轴向应力分布数据。
11. "RT-A2R0.4P1.xlsx"：FRP约束长宽比2.0的矩形试样（RT-A2R0.4P1）应力-应变曲线上四个特征点的轴向应力分布数据。
12. "RT-A2R0.4P2.xlsx"：FRP约束长宽比2.0的矩形试样（RT-A2R0.4P2）应力-应变曲线上四个特征点的轴向应力分布数据。

所有数据已在以下学术论文中进行详细分析与呈现：
李鹏达，高思杰，吴玉飞. 非均匀被动约束混凝土中的应力分布。