PSI - Issue 22

Lunwen Guo et al. / Procedia Structural Integrity 22 (2019) 194–200 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

200

7

Double-layer metal pipe

Cracking and peeling off

4.0

3.04

CFRP-steel pipe

6.2

2.23

Worn out

5. Conclusions According to the calculation results and experimental test, it can be concluded as the following: (1) The CFRP-steel concrete pumping pipes was designed consisted of high hardness inner liner, high toughness flanges and the high strength fiber layer, and the fiber layer of CFRP-steel pipe contained the stress sharing inner layer, the explosion-proof outer layer and the middle layer of connection to steel flanges. (2) Based on the principle of stress sharing of hybrid structure, the thickness of the stress sharing inner layer and the explosion-proof outer layer were calculated and tested at 1.5mm respectively, and the prestress of carbon fiber at 35MPa was reasonable. (3) The connection solution of CFRP to metal flange is about filament winding on pins, and the flange structure with these pins was developed. It was proved that the pin radius is 9 mm, the winding angle is 17°, and the winded filament number on single pin are 18 bundles. The CFRP-steel pipes can withstand 17MPa inner pressure and 210kN axial loading. References [1] Kyong Pil Jang, Myoung Sung Choi. How affect the pipe length of pumping circuit on concrete pumping. Constuction and Building Materials. 208(3), 758-766(2019). [2] X.Y. Gao, T. Balendra, C.G. Koh. Buckling strength of slender circular tubular steel braces strengthened by CFRP. Engineering Structures, 46(2), 547 – 556 (2013). [3] Tien-Cuong Nguyen, Yu Bai, Xiao-Ling Zhao, Riadh Al-Mahaidi. Curing effects on steel/CFRP double strap joints under combined mechanical load, temperature and humidity. Construction and Building Materials, 40(3), 899 – 907(2013). [4] M.R. Bambach, H.H. Jama, M. Elchalakani. Axial capacity and design of thin-walled steel SHS strengthened with CFRP. Thin-Walled Structures, 47(10), 1112 – 1121 (2009). [5] B. Lanier, D. Schnerch, S. Rizkalla. Behavior of steel monopoles strengthened with high-modulus CFRP materials. Thin-Walled Structures, 47(10), 1037 – 1047 (2009). [6] Fuming Peng. Research on the interfacial performance of metallic structures strengthened with fibre reinforced polymers. XAUAT, Xi’an (2005).