2Harajli M, et al. Externally prestressed members: Evaluation of second-order effects. Journal of Structural Engineering, ASCE, 1999,125(10): 1151
3Ariyawardena N D, et al. Prestressing with unbonded internal or external tendons: Analysis and computer model. Journal of Structural Engineering, ASCE, 2002, 128(12): 1493
5ISO/IEC 18004:2006(E) Information tcchn~logy I Automatic identification and data capture techniques -- QR Code 2005 bar code symbology specification[S].
