鋼筋混凝土矩形斷面上層鋼筋的深度公式

ACI Structural Journal
Jan. 28, 2016
Title
　　The Depth Formula of the Upper Rebar for the Rectangle Section
Abstract
　　The depth formula of upper rebar is proposed to correct the rebar position for the engineer and software.
Keywords: The Depth Formula of the Upper Rebar, Rectangle Section

I.　　The Depth Formula of the Upper Rebar for the Rectangle Section

　　In the present calculation, the engineer and software adopt the incorrect depth of the upper rebar for the rectangle section, and the depth of the bottom rebar also has the incorrect depth by the same calculation, d=h-d'. The theoretical calculation is proposed by the following formula, and the curved radius of the stirrup is considered by the formula, R=Nd_bh.


　

where d is the depth of the bottom rebar, d' is the depth of the upper rebar, h is the full depth of the member section, R is the curved radius of the stirrup, N is the multiple of the stirrup diameter, d_bh is the diameter of the stirrup, d_b is the diameter of the rebar, and c is the thickness of the concrete cover.

　　In the general case, the rebar and stirrup are the #8 and #4 respectively, and the depth of the upper rebar may be defined by the following formula.


　

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