Portal frames resist horizontal and vertical loads mainly by（ ）.(There is not less than one correct choice)
A. rigidity of connection
B. bending stiffness of columns
C. bending stiffness of rafters
D. bending stiffness of haunch
In the literature search, which set of keywords can quickly retrieve the reference literature on the design theory of light-steel structure factory?
A. steel structure factory, design theory
B. factory, design theory
C. portal frame, concrete
D. factory, design
Which of the following references citation is in accordance with China's standard of reference citation?
A. [1] Ngian, S.P., Tahir, M.M., Sulaiman, A. et al. Wind-moment design of semi-rigid un-braced steel frames using cruciform column (CCUB) section. Int J Steel Struct 15, 115–124 (2015).
B. [1] Ngian, S.P., Tahir, M.M., Sulaiman, A. et al. Wind-moment design of semi-rigid un-braced steel frames using cruciform column (CCUB) section[J]. Int J Steel Struct 15, 115–124 (2015).
C. [1] Ngian, S.P., Tahir, M.M., Sulaiman, A. et al. Wind-moment design of semi-rigid un-braced steel frames using cruciform column (CCUB) section[J]. Int J Steel Struct 2015, 15, 115–124.
D. [1] Ngian, S.P., Tahir, M.M., Sulaiman, A. et al. Wind-moment design of semi-rigid un-braced steel frames using cruciform column (CCUB) section[J]. Int J Steel Struct 2015, 15: 115–124.
微信支付 
支付宝支付