﻿ 轴压下圆形钢管混凝土短柱承载力的简化计算 Simplified Calculation of Ultimate Strength for Axial-Loaded Circular CFT Stub Columns

Hans Journal of Civil Engineering
Vol.07 No.05(2018), Article ID:26640,4 pages
10.12677/HJCE.2018.75078

Simplified Calculation of Ultimate Strength for Axial-Loaded Circular CFT Stub Columns

Gang Sun1, Xianrong Zhuo1, Guixin Ou2, Huayao Qiu1

1College of City Construction, Zhongkai University of Agriculture and Engineering, Guangzhou Guangdong

2Guangzhou Zhongda Vocational School of Science and Education, Guangzhou Guangdong

Received: Aug. 5th, 2018; accepted: Aug. 22nd, 2018; published: Aug. 29th, 2018

ABSTRACT

In this paper, the bearing mechanism of axial-loaded circular concrete-filled steel tube (CFT) stub column is analyzed. Based on experimental results, the increase coefficient of concrete strength and the reduction ratio of steel longitudinal stress are analyzed and determined. Then, the simplified calculation equations of circular concrete-filled steel tube stub columns subjected to axial load are proposed. Finally, 28 specimens are calculated with the proposed equations, and the calculated results agree with the experimental and normative ones very well.

Keywords:Circular Concrete-Filled Steel Tube, Stub Column, Ultimate Strength

1仲恺农业工程学院城市建设学院，广东 广州

2广州市中大科教职业培训学校，广东 广州

1. 引言

2. 圆形钢管混凝土的受力机理

${N}_{u}={k}_{1}{f}_{c}{A}_{c}+{k}_{2}{f}_{y}{A}_{s}$ (1)

3. 圆形钢管混凝土轴压短柱承载力的简化计算

3.1. 核心混凝土纵向受压强度提高系数

$\delta ={f}_{y}{A}_{s}/{f}_{c}{A}_{c}$ (2)

${k}_{1}=0.394\delta +1.0156$ (3)

3.2. 圆钢管纵向强度折减系数

${k}_{2}=0.83$ (4)

4. 试验验证

Table 1. Comparison of ultimate strength between calculated results and experimental and normative ones of axial-loaded results of circular CFT stub columns

Figure 1. Regressive curve of k1 and δ

5. 结语

1) 采用混凝土纵向强度提高系数和钢管纵向强度折减系数建立圆形钢管混凝土轴压短柱承载力简化计算的公式，表达式简单，力学概念清晰，参数物理意义明确；

2) 用建议表达式对圆形钢管混凝土轴压试件进行计算，计算结果与试验结果吻合良好；

3) 建议公式可为该类构件的工程设计提供参考。

Simplified Calculation of Ultimate Strength for Axial-Loaded Circular CFT Stub Columns[J]. 土木工程, 2018, 07(05): 667-670. https://doi.org/10.12677/HJCE.2018.75078

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