玻璃纤维增强聚合物复合材料约束壁式钢管混凝土短柱轴压性能试验

程杰; 齐玉军; 谢志锦

doi:10.13801/j.cnki.fhclxb.20200827.001

玻璃纤维增强聚合物复合材料约束壁式钢管混凝土短柱轴压性能试验

doi: 10.13801/j.cnki.fhclxb.20200827.001

南京工业大学　土木工程学院，南京 211816

基金项目: 国家自然科学基金面上项目(51778286)；江苏省基础研究计划(自然科学基金)面上项目(BK20171469)

详细信息

通讯作者:
齐玉军，博士，教授，研究方向为新材料及新型结构　Email：qiyujun@njtech.edu.cn

中图分类号: TU398.9
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出版历程
- 收稿日期: 2020-06-15
- 录用日期: 2020-08-14
- 网络出版日期: 2020-08-28
- 刊出日期: 2021-06-23

Experiment on axial compression performance of glass fiber reinforced polymer-walled concrete-filled steel tube columns

College of Civil Engineering, Nanjing Tech University, Nanjing 211816, China

摘要

摘要: 为研究玻璃纤维增强聚合物复合材料(GFRP)约束壁式钢管混凝土矩形短柱的轴压力学性能，对1组无GFRP约束试件和2组GFRP约束试件进行静力轴压试验；根据试验结果提出壁式柱的强弱约束模型，并基于双剪统一强度理论建立GFRP约束壁式钢管混凝土柱的轴压承载力计算公式；最后建立有限元模型，将计算结果与试验对比，并进行参数化分析，研究钢材屈服强度和混凝土强度对新型壁式钢管混凝土柱轴压性能的影响。结果表明：壁式钢管混凝土柱最终因柱中混凝土压碎、钢管屈曲、试件变形过大而失效；钢材在试件第二线性段起点处开始屈服，钢材强度得到充分发挥，GFRP能有效提高构件峰值承载力，但延性有所下降；理论公式计算结果与试验值吻合较好；混凝土强度及钢材屈服强度均能有效提高承载能力，且钢材屈服强度对承载力的影响明显大于混凝土强度的影响。
- 玻璃纤维增强聚合物复合材料 /
- 壁式钢管混凝土柱 /
- 矩形截面 /
- 承载力 /
- 参数分析
Abstract: In order to study the axial compression performance of glass fiber reinforced polymer (GFRP)-walled concrete-filled steel tube columns, the static axial compression tests were conducted on a group of non-GFRP constrained specimens and two groups of GFRP constrained specimens. According to the test results, a strong and weak constraint model of the wall column was proposed. Based on the twin-shear unified strength theory, the formula was established to calculate the axial compression bearing capacity of the GFRP-walled concrete-filled steel tube columns. Finally, the theoretical results, obtained through the establishment of the finite element model, were compared with the experimental results. And a parametric analysis was used to study the effect of the yield strength of steel and the strength of concrete on the axial compression performance of the new type wall-filled concrete-filled steel tube columns. The results show that the wall-filled concrete-filled steel tube columns eventually fail due to crushing of the concrete, buckling of the steel tube and excessive deformation of the specimens. At the beginning of the second linear section of the specimen, the steel begins to yield and its strength is fully exerted, which demonstrates that GFRP can effectively improve the peak load of the member, however, the ductility has decreased. The results of the theoretical formula are in agreement with the experimental results. The bearing capacity can be improved by increasing the strength of concrete and the yield strength of the steel. Compared with the strength of concrete, the yield strength of steel bars has a greater influence on the bearing capacity.
- glass fiber reinforced polymer /
- walled concrete-filled steel tube column /
- rectangular section /
- bearing capacity /
- parameter analysis

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图 1 壁式柱典型构造

Figure 1. Typical structure of wall column

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图 2 试件几何尺寸及构造

Figure 2. Geometrical dimensions and structure of the specimens

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图 3 GFRP约束壁式钢管混凝土柱轴压试验加载装置

Figure 3. Axial compressive test setup of GFRP-walled concrete-filled steel tube columns

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图 4 试验柱测点布置

Figure 4. Arrangement of measuring points for tested columns

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图 5 C30-G0-1的破坏过程

Figure 5. Failure process of C30-G0-1

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图 6 C30-G2-1的破坏过程

Figure 6. Failure process of C30-G2-1

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图 7 GFRP约束壁式钢管混凝土柱轴向荷载-位移曲线

Figure 7. Axial load-deformation curves of GFRP-walled concrete-filled steel tube columns

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图 8 FRP-钢复合约束混凝土典型轴向荷载-位移曲线

Figure 8. Typical curves of axial load-displacement of FRP concrete filled steel tube

OA—Elastic stage; AB—Elastic-plastic stage; BC—Plastic strengthening stage; CD—Softening stage

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图 9 钢管截面应力-应变曲线

Figure 9. Stress-strain curves of steel pipe section

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图 10 GFRP约束壁式钢管混凝土柱强弱约束分布

Figure 10. Distribution of strong and weak constraints of GFRP-walled concrete-filled steel tube columns

R_c—Chamfer radius; θ₁ and θ₂—Original angle; t—Pipe wall thickness; d—Thickness of the inner partition; h and b—Long and short side of steel pipes

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图 11 钢管截面受力示意图

Figure 11. Schematic diagram of cross-section force of steel pipe

${f_{{\rm{l1}}}} $ and ${f_{{\rm{l2}}}} $—Equivalent lateral restraint stress of rectangular steel tube long side and short side to core concrete respectively; ${f'_{{\rm{l1}}}} $ and ${f'_{{\rm{l2}}}} $—Average lateral constraint forces of long side and short side of rectangular steel tube, respectively; ${f'_{{\rm{sr2}}}} $—Circumferential stress of inner diaphragm; ${f_{{\rm{sr1}}}} $ and ${f_{{\rm{sr2}}}} $—Hoop stresses of long side and short side of wall steel tube, respectively

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图 12 GFRP约束壁式钢管混凝土柱模型

Figure 12. GFRP-confined steel reinforced concrete column model

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图 13 GFRP约束壁式钢管混凝土短柱荷载-位移曲线对比

Figure 13. Comparison of load-displacement curves of GFRP-walled concrete-filled steel tube columns

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图 14 不同钢材、混凝土强度的GFRP约束壁式钢管混凝土短柱荷载-位移曲线

Figure 14. Load-displacement curves of GFRP-walled concrete-filled steel tube columns with different steel and concrete strength

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表 1 玻璃纤维增强聚合物复合材料(GFRP)约束壁式钢管混凝土柱参数

Table 1. Parameters of glass fiber reinforce polymer (GFRP)-walled concrete-filled steel tube columns

Number	b×h×L/mm	t/mm	d/mm	R_c/mm	Fiber layer
C30-G0-1	100×200×600	5	5	15	0
C30-G0-2	100×200×600	5	5	15	0
C30-G2-1	100×200×600	5	5	15	2
C30-G2-2	100×200×600	5	5	15	2
C30-G4-1	100×200×600	5	5	15	4
C30-G4-2	100×200×600	5	5	15	4
Notes: C—Concrete, the number stands for the concrete grade; G—GFRP, the numbers are the number of package layers; 1 and 2—Two different test pieces; B—Length; h—Width; L—Height; t—Wall thickness; d—Thickness of the separator; R_c—Radius of the chamfer.

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表 2 钢材和混凝土的材料力学性能

Table 2. Material mechanical properties of steel and concrete

Material	${f_{\rm{y}}}/{\rm{MPa}}$	$E/{\rm{GPa}}$	${f_{{\rm{cu}}}}/{\rm{MPa}}$
Concrete	—	—	32.4
Steel plate	251	196	—
Notes: f_y—Yield strength; E—Tensile modulus; f_cu—Cube compressive strength.

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表 3 GFRP布的材料力学性能

Table 3. Mechanical properties of GFRP

Material	${\sigma _{\rm{b}}}/{\rm{MPa}}$	$E/{\rm{GPa}}$
GFRP	537.4	28.7
Note: ${\sigma _{\rm{b}}}$—Tensile strength.

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表 4 GFRP约束壁式钢管混凝土柱主要试验结果

Table 4. Main test results of GFRP-walled concrete-filled steel tube columns

Number	${N_{\rm{p}}}$/kN	${N_{{\rm{p1}}}}$/kN	I/%
C30-G0-1	1 480	1 477	-
C30-G0-2	1 475	1 477	-
C30-G2-1	1 691	1 692	15
C30-G2-2	1 708	1 692	15
C30-G4-1	1 877	1 878	27
C30-G4-2	1 879	1 878	27
Notes: N_p—Peak load; N_p1—Average value of the peak load; I—Increment of N_p1.

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表 5 GFRP约束壁式钢管混凝土柱延性系数

Table 5. Ductility coefficients of GFRP-walled concrete-filled steel tube columns

Number	${e_{\rm{u}}}$/mm	${e_{\rm{y}}}$/mm	$\mu $	$\overline \mu $
C30-G0-1	—	5.12	—	11.53
C30-G0-2	60.11	5.08	11.53	11.53
C30-G2-1	58.76	5.71	10.29	10.97
C30-G2-2	65.64	5.64	11.64	10.97
C30-G4-1	56.09	6.15	9.12	10.53
C30-G4-2	60.27	5.21	11.57	10.53
Notes: e_u—Longitudinal displacement corresponding to the peak load; e_y—Longitudinal displacement corresponding to the yield bearing capacity; $\mu $—Ductility coefficient；$\overline \mu $—Average ductility coefficient of each group.

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表 6 GFRP约束壁式钢管混凝土柱承载力计算值与试验值对比

Table 6. Comparison of calculation and test value of bearing capacity of GFRP-walled concrete-filled steel tube columns

Number	${\varepsilon _{\rm{v}}}$/10⁻⁶	${t_{\rm{f}}}$/mm	${A_{\rm{s}}}$/mm²	${A_{\rm{c}}}$/mm²	${N_{\rm{p}}}$/kN	${N_{{\rm{pre}}}}$/kN	${N_{\rm{p}}}/{N_{{\rm{pre}}}}$	${\overline X _1}$
C30-G0-1	—	0	2 957	16 336	1 480	—	—	1.06
C30-G0-2	—	0			1 475	1 393	1.06	1.06
C30-G2-1	4 968	1.2			1 691	1 568	1.07	1.09
C30-G2-2	6 080	1.2			1 708	1 550	1.10	1.09
C30-G4-1	10 672	2.4			1 877	1 672	1.12	1.12
C30-G4-2	10 700	2.4			1 879	1 684	1.12	1.12
$\overline X $	—	—	—	—	—	—	1.09
${\sigma _{\rm{S} } }$	—	—	—	—	—	—	0.028
Notes: ε_v—Measured value of the high-circumferential strain of the corresponding column when GFRP breaks; t_f—Thickness of GFRP; A_s—Effective cross-sectional area of the steel tube; A_c—Effective cross-sectional area of the concrete; N_p—Peak load; N_pre—Theoretically calculated value of peak load; N_p/N_pre—Ratio of the test value and the calculated value; ${\overline X _1}$—Average ratio of each group; $\overline X $—Mean of the ratio; ${\sigma _{\rm{S}}}$—Standard deviation of the ratio.

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表 7 塑性损伤参数取值

Table 7. Concrete damaged plasticity parameter values

$\psi $	$\varepsilon $	${\sigma _{{\rm{bo}}}}/{\sigma _{{\rm{co}}}}$	${K_{\rm{c}}}$	$\mu $
30	0.1	1.16	0.6667	0.005
Notes: $\psi $—Expansion angle; $\varepsilon $—Eccentricity; ${\sigma _{{\rm{bo}}}}/{\sigma _{{\rm{co}}}}$—Ratio of the biaxial compressive strength to the uniaxial compressive ultimate strength value; ${K_{\rm{c}}}$—Ratio of the invariable stress; $\mu $—Viscous parameter.

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表 8 GFRP约束壁式钢管混凝土短柱有限元结果与试验对比

Table 8. Comparison of finite element results and test results of GFRP-walled concrete-filled steel tube columns

Number	Fiber layer	${N_{{\rm{p1}}}}$/kN	${N_{{\rm{Aba}}}}$/kN	${N_{{\rm{p1}}}}$/${N_{{\rm{Aba}}}}$
C30-G0	0	1477	1516	0.97
C30-G2	2	1692	1747	0.97
C30-G4	4	1 878	1 981	0.95
Notes: N_p1—Average value of the peak load; N_Aba—Peak load of the finite element simulation; N_p1/N_Aba—Ratio of the measured peak load to the finite element simulated peak load.

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表 9 GFRP约束壁式钢管混凝土短柱模拟试件几何尺寸与材料强度

Table 9. Geometric dimensions and material strength of simulated specimens of GFRP-walled concrete-filled steel tube columns

Number	f_cu/MPa	f_y/MPa
TS-235-G2	30	235
TS-345-G2	30	345
TS-420-G2	30	420
TS-460-G2	30	460
TC-C30-G2	30	235
TC-C40-G2	40	235
TC-C50-G2	50	235
TC-C60-G2	60	235
Notes: T—Test; S—Steel; C—Concrete; G—GFRP; Numbers behind indicate the corresponding labels and types of materials; f_cu—Concrete strength; f_y—Steel yield strength.

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表 10 不同钢材屈服强度的GFRP约束壁式钢管混凝土短柱有限元模拟结果

Table 10. Simulated results of GFRP-walled concrete-filled steel tube columns with different yield strength of steels

Number	f_y/MPa	N_y/kN	N_p/kN	I₁/%
TS-235-G2	235	1516	1767	—
TS-345-G2	345	1 817	2572	45.55
TS-420-G2	420	1 997	2845	61.01
TS-460-G2	460	2084	3009	70.29
Notes: N_y—Yield load; N_p—Peak load; I₁—Increment of N_p.

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表 11 不同混凝土强度的GFRP约束壁式钢管混凝土短柱有限元模拟结果

Table 11. Simulated results of GFRP-walled concrete-filled steel tube columns with different strengths of concrete

Number	f_y/MPa	N_y/kN	N_p/kN	I₁/%
TC-C30-G2	30	1516	1767	—
TC-C40-G2	40	1563	1 880	6.40
TC-C50-G2	50	1598	1 970	11.45
TC-C60-G2	60	1614	2083	17.89

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