求助。
高强螺栓施工，用转角法拧紧时，初拧达到‘密贴’状态后，再加拧一个角度，完成终拧。有谁能指教，初拧的轴力为多少才合适？有没有这方面的规定，或者论述？
Hi! Everybody, who can kindly help with the solution about how to determine the initial pre-tesion force corresponding to 'snug tight' state when turn-of the-nut method is applied for tightening high strength bolt? I read of some descriptions on 'snug tight' from AISC web, and some project specifications, but never quantified requirement.  
Thanks in advance.