steel plate and z-k8凯发官网
steel plate and z-direction steel plate for high-rise building structure
1 main use
the steel plates for high-rise buildings are easy to weld, earthquake-resistant, and resistant to low-temperature impact. they are mainly used in large-scale projects such as high-rise buildings, super high-rise buildings, large-span stadiums, airports, convention centers, and steel structures. compared with the ordinary q235b/q345b steel plate, the upper limit of the yield strength and the tensile strength are increased, and the requirements of the carbon equivalent and the yield ratio are increased.
2 grades and standards
grade: q235gjb/c/d, q345gjb/c/d; q235b/c/d-z15/z25/z35, q345b/c/d/e-z15/z25/z35, q235gjb/c/d-z15/z25/ z35, q345gjb/c/d/e-z15/25/z35
standard: gb/t19879-2005 "steel for building structure", gb5313-1985 thickness direction performance steel plate
3 technical conditions of supply
3.1 product specifications
6～100×1800～4000×lmm
3.2 chemical composition
table 1 chemical composition, %
brand | quality level | c≤ | si≤ | mn | p≤ | s≤ | als |
q235gj | b、c | 0.20 | 0.35 | o.60～1.20 | 0.025 | 0.015 | ≥0.015 |
d | 0.18 | 0.020 | |||||
q345gj | b、c | 0.20 | 0.55 | ≤1.60 | 0.025 | 0.015 | ≥0.015 |
d | 0.18 | 0.020 |
note: z-direction performance steel plate, steel plate s content is carried out according to gb/t5313-85 standard, z-direction performance steel plate after steel number is marked corresponding to z-direction.
表2，％
brand | delivery status | carbon equivalent ceq | crack sensitivity index pcm |
≤50mm | |||
q235gj | hot rolled or normalized | ≤0.36 | ≤0.26 |
q345gj | hot rolled or normalized | ≤0.42 | ≤0.29 |
3.4steel plate mechanical properties
table 3 mechanical properties
brand | rel ,mpa | rm mpa | a，%,≥ | 纵向akv，j | 180°弯曲 | 屈强比 rel/rm | |||||
规格，mm | |||||||||||
6～16 | >16～35 | >35～50 | >50～100 | ℃ | ≥ | 6～16 | >16～100 | ||||
q235gjb | ≥235 | 235～345 | 225～335 | 215～325 | 400～510 | 23 | 20 | 34 | d=2a | 3a | ≤0.80 |
q235gjc | 0 | ||||||||||
q235gjd | -20 | ||||||||||
q345gjb | ≥345 | 345～455 | 335～445 | 325～435 | 490～610 | 22 | 20 | 34 | d=2a | 3a | ≤0.83 |
q345gjc | 0 | ||||||||||
q345gjd | -20 | ||||||||||
表4 thickness direction performance
等级 | 端面收缩率，ψz，% | |
均值 | 单值 | |
z15 | ≥15 | ≥10 |
z25 | ≥25 | ≥15 |
z35 | ≥35 | ≥25 |