Issue 46

W. Hao et alii, Frattura ed Integrità Strutturale, 46 (2018) 391-399; DOI: 10.3221/IGF-ESIS.46.36 398 C ONCLUSIONS (1) Through experimental observations, it was found that the appearances of the eccentrically loaded RPC filled square steel tubular columns did not change much until the ultimate load was reached. The final failure was caused by the local bending of the steel tube. The bent part gradually shifted from the two ends to the mid section of the specimen. (2) The load-displacement curve of an eccentrically loaded RPC filled square steel tubular column can be roughly divided into three stages: the linear elastic stage, the elastic-plastic stage and the descending stage. The descending section of the curve is relatively flat, which shows that the specimen had good ductility. As the increase of specimen slenderness ratio and eccentricity, the bearing capacity of specimens is gradually decreased, the increase of steel ratio and the confinement coefficient obviously improves the bearing capacity of specimens. (3) According to theoretical analysis, it is found that the results of bearing capacity test and CECS28-2012 calculation show that the average value of Nu/N is 1.043. Compared with other specifications (or codes), the calculated results are close to the test results and are conservative. Therefore, the formula provided in CECS28-2012 is recommended for calculation of the bearing capacity of RPC filled square steel tubular column in engineering practice. (4) The simulation analysis results of Abaqus are close to the experiment results, indicating that this finite element model is correct and reasonable and can provide theoretical reference for engineering practice. A CKNOWLEDGMENTS he research work was supported by Science and Technology Research Project of Colleges and Universities in Hebei Province (No. ZD2018209) and Key Research and Development Project of Hebei Province (No. 18227209D). R EFERENCES [1] Richard, P. and Cheyrezy, M. (1995). Composition of powder concretes, Cement and Concrete Research, 25(7), pp. 1501-1511. [2] Hao, W.X. and Xu, X. (2012). Experimental study on the mechanical properties of reactive powder concrete with steel fibre, Architecture Technology, 43(1), pp. 35-37. [3] Hao, W.X. and Xu, X. (2010). Experimental study on the flexural behavior of reactive powder concrete with steel fibre, Concrete, (10), pp. 53-55. [4] Hu, N.D., Du, X.K., Liu, P. and Niu, Z. (2016). Experimental study on mechanical behavior of recycled aggregate concrete-filled square steel tubular long columns under eccentric compression loading, Journal of Building Structures, (S2), pp. 36-42. [5] Chen, X.X. (2014). Experimental study on mechanical behavior of recycled aggregate concrete-filled square steel tubular short columns, Baoding: College of Urban and Rural Construction, Agricultural University of Hebei. [6] Lin, Z.Y., Wu, Y.H. and Shen, Z.Y. (2005). Research on behavior of RPC filled circular steel tube column subjected to axial compression, Journal of Building Structures, 26(4), pp. 52-57. [7] Song, J. and Chen, F.Y. (2015). Calculation model for thermo-mechanical coupling and 3D numerical simulation for concrete tower of cable-stayed bridge, Mathematical Modelling of Engineering Problems, 2(1), pp. 9-12. [8] American Institute of Steel Construction. (2005). AISC(2005) Seismic provisions for structural steel buildings, Chicago, IL. [9] China Association for standardization of engineering construction. (2012). CECS 28-2012 Technical specification for concrete-filled steel tubular structures, Beijing: China planning press. [10] China Association for standardization of engineering construction. (2013). DBJ13-51-2003 Technical specification for concrete-filled steel tubular structures, Beijing: China architecture and building Press. [11] Chinese national military standard. (2000). GJB4142-2000 Technical specifications for early-strength model composite structure used for navy port emergency repair in wartime. Beijing: The general logistics department of PLA. [12] China Association for standardization of engineering construction. (2013). GB50936-2014 Technical code for concrete filled steel tubular structures, Beijing: China architecture and building press. T