Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Mathinline
body$$ \normalsize u_p=2\times(b_1+b_2) = 2\times(124+74) = 396 \; cm = 3.96 \; cm m $$

Mathinline
body--uriencoded--$$ \normalsize A_z=u_p\times d = 3.96\times0.24=0.9504 \; m%5e2 $$

...

Mathinline
body--uriencoded--$$ \normalsize c'_%7B(maj)%7D = b_1-c_%7B(maj)%7D= 124-62=62 \; cm = 0.62 \; m $$

In this case, the The polar inertia and the two second moments of inertia are respectively calculated as follows, respectively.

...

Mathinline
body--uriencoded--$$ \normalsize J_%7B1(maj)%7D = \left( \frac%7Bb_1d%5e3%7D%7B12%7D + \frac%7Bb_1%5e3d%7D%7B12%7D \right) \times 2 = \left( \frac%7B1.24 \times 0.24%5e3%7D%7B12%7D + \frac%7B1.24%5e3 \times 0.24%7D%7B12%7D \right) \times 2 = 0.079122 \; m%5e4 $$

Mathinline
body--uriencoded--$$ \normalsize J_%7B2(maj)%7D = b_2 d \times c%5e2_%7B(maj)%7D \times 2 = 0.74 \times 0.24 \times 0.62%5e2 \times 2= 0.1365388 \; m%5e4 $$

In this case, the sum of the polar inertia and the second moments of inertia J about the strong (majmajor) with respect to the major axis of the section, J (maj) , is found as follows.

Mathinline
body--uriencoded--$$ \normalsize J_%7B(maj)%7D = J
1
_%7B1(maj)%7D + J
2
_%7B2(maj)%7D = 0.079122 + 0.1365388 = 0.
21566080 m 4
2156608 \; m%5e4 = 21566080
cm 4
\; cm%5e4 $$

Calculation of J and γf Coefficients for Weak Axis (Minor Direction) to J and γ f Coefficient AccountFor

The following steps are followed for the calculation of the γ f(min) and γ v (min) coefficient, the following steps are followed.

...

The following method is used to find the (min) coefficients.

Mathinline
body--uriencoded--$$ \normalsize \gamma_%7Bf(min)%7D = \frac %7B1%7D %7B1+\frac 2 3 \sqrt%7Bb_2/b_1%7D%7D = \frac %7B1%7D %7B1+\frac 2 3 \sqrt%7B0.74/1.24%7D%7D = 0.660 \; $$

Mathinline
body--uriencoded--$$ \normalsize \gamma_%7Bv(min)%7D =1- \gamma_%7Bf(maj)%7D = 1-0.66 = 0.340 $$

The J(min) value is found as follows.

The c(min) value is the center of gravity distance perpendicular to the moment vector, which is considered whenfinding the J value (J (min)) on the strong weak axis of the section. Since the punching circumference is rectangular;

Mathinline
body--uriencoded--$$ \normalsize c_%7B(min)%7D = b
1
_2/2 = 74/2=37 \; cm = 0.37 \; m $$

Mathinline
body--uriencoded--$$ \normalsize c'_%7B(min)%7D = b
1
_2-c_%7B(min)%7D= 74-37=37 \; cm = 0.37 \; m $$

In this case, the polar moments of inertia and the two second moments of inertia are respectively found as follows, respectively.

...

Mathinline
body--uriencoded--$$ \normalsize J_%7B1(min)%7D = \left( \frac%7Bb_2d%5e3%7D%7B12%7D + \frac%7Bb_2%5e3d%7D%7B12%7D \right) \times 2 = \left( \frac%7B0.74 \times 0.24%5e3%7D%7B12%7D + \frac%7B0.74%5e3 \times 0.24%7D%7B12%7D \right) \times 2 = 0.01791392 \; m%5e4 $$

Mathinline
body--uriencoded--$$ \normalsize J_%7B2(min)%7D = b_1 d \times c%5e2_%7B(min)%7D \times 2 = 1.24 \times 0.24 \times 0.37%5e2 \times 2= 0.08148288 \; m%5e4 $$

In this case, the sum of the polar inertia and the second moments of inertia J about the weak (minminor) with respect to the minor axis of the section, J (min) , is found as follows.

Mathinline
body--uriencoded--$$ \normalsize J_%7B(min)%7D = J
1
_%7B1(min)%7D + J
2
_%7B2(min)%7D = 0.
017914
01791392 + 0.
081483
08148288 = 0.0993968
m 4
\; m%5e4 = 9939680
cm 4
\; cm%5e4 $$

Finding Punching Stresses

The forces to be considered for punching stresses and the values ​​obtained obtained from hand the geometry are given below.

  • Vd = 679.31 kN

  • DMd(maj) = 394.624 kNm

  • DMd(min) = 65.3914 kNm

  • Az = 0.

...

  • 9504 m2

  • γf(maj) = 0.537

  • γv(maj) = 0.463

  • γf(min) = 0.660

  • γv(min) = 0.340

  • J(maj) =

...

  • 0.

...

  • 2156608 m4

...

  • J(min) = = 0.0993968 m4 ,

  • c(maj) = 0.62 m

...

  • c(min) = 0.37 m

...

  • c'(maj) = 0.62 m

...

  • c'(min) = 0.37 m

If we substitute The punching stresses are found by substituting all the above values ​​we found above for in the stress formulas together with the internal forces based on the punching design;

...

Among the values ​​of essential to the punching design.

Mathinline
body--uriencoded--$$ \normalsize \tau_%7Bpd,1%7D = \frac %7BV_d%7D%7BA_z%7D + \frac %7B \gamma_%7Bv(maj)%7DDM_%7Bd(maj)%7Dc_%7B(maj)%7D %7D %7BJ_%7B(maj)%7D%7D + \frac %7B \gamma_%7Bv(min)%7DDM_%7Bd(min)%7Dc_%7B(min)%7D %7D %7BJ_%7B(min)%7D%7D $$

Mathinline
body--uriencoded--$$ \normalsize \tau_%7Bpd,2%7D = \frac %7BV_d%7D%7BA_z%7D - \frac %7B \gamma_%7Bv(maj)%7DDM_%7Bd(maj)%7Dc_%7B(maj)%7D %7D %7BJ_%7B(maj)%7D%7D - \frac %7B \gamma_%7Bv(min)%7DDM_%7Bd(min)%7Dc_%7B(min)%7D %7D %7BJ_%7B(min)%7D%7D $$

Mathinline
body--uriencoded--$$ \normalsize \tau_%7Bpd,1%7D = \frac %7B679.31%7D%7B0.9504%7D + \frac %7B 0.463 \times 394.624 \times 0.62 %7D %7B0.2156608%7D + \frac %7B 0.34 \times 65.39 \times 0.37 %7D %7B0.0993968%7D = 1322.795 \; kN/m%5e2 $$

Mathinline
body--uriencoded--$$ \normalsize \tau_%7Bpd,2%7D = \frac %7B679.31%7D%7B0.9504%7D - \frac %7B 0.463 \times 394.624 \times 0.62 %7D %7B0.2156608%7D - \frac %7B 0.34 \times 65.39 \times 0.37 %7D %7B0.0993968%7D = 106.73 \; kN/m%5e2 $$

The absolute value of τ pd,1, τ pd,2, the absolute value is τ pd,1 = 13231322.0 795 kN/m 2 . If we compare this value with This obtained value is compared with the fctd value, which is the concrete designtensile strength f ctd value;.

τpd,1 = 13231322.0 795 kN/m2 <f < fctd = 1380.42 kN/m2

We reach the result. From here, we can conclude that the Upholstery punching strength of this column is sufficient. These values ​​can also be compared with the report results.

Related Topics

...

Punching Shear Check

...

Punching Shear Stress at Critical Section (7.11.8)

...

(8.3.1) TS500 Puching Shear Design Conditions

...

Punching Shear Stress Check Report

...

Panel
panelIconIdatlassian-info
panelIcon:info:
bgColor#E6FCFF

Download ideCAD for ACI 318-19