📚 설계 6종 비교 (어느 기준의 어느 식을 썼고, 같은 예제에서 얼마가 나오는지)🏠 SJ Tech 홈📧 strustar@konyang.ac.kr닫기

✂️ 전단 설계, 기준 6종 비교 (조항, 식, 원문, 계산)

조항 클릭 → 원문 PDF 그 쪽식 번호↗ 참조 조항파란 블록 = 예제 값 대입 계산점선 카드 = 참고용(비교 열 아님)
⚠ 어떤 원문이 열리나 (기준마다 다름)
KDS, KCS (국토교통부 고시)  →  누구나 열람. 저작권법 제7조 비보호 저작물이며 국가건설기준센터에서 무료로 받을 수 있음.
ACI, AASHTO (해외 기준)  →  저작권 자료라 이 PC에 있는 사본으로만 열람. 링크가 안 열리면 발행처 공식 미리보기, 상점으로 연결됨.
도로공사 지침  →  발주처 내부 자료라 비공개. 조항 번호와 내용만 표에 옮겨 적었다.
원문 PDF는 웨일, 크롬에서 열면 해당 쪽과 위치까지 자동으로 이동함.
🧮 예제 값$b$ = 400 mm, $h$ = 600 mm, $d$ = 509 mm, $f_{ck}$ = 30 MPa, $A$ = 3,040 mm², $V_u$ = 150 kN
📊 기준 6종 비교 차트 (같은 예제에서 기준별 값)
노란 테두리 = 지금 고른 FRP 기준붉은 점선 = 모든 기준에 같은 한계붉은 짧은 선 + 숫자 = 그 기준만의 한계
약칭 KDS 14 = KDS 14 20 68 (건축, 일반), KDS 24 = KDS 24 50 05 (교량), ACI 15 = ACI 440.1R-15, ACI 22 = ACI 440.11-22, AASHTO = AASHTO GFRP 보강 콘크리트교 설계지침 2판 (2018)
최대 이용률 Vu/ϕVn- - 점선: 1.0 = 한계작용 전단력 대 설계전단강도1.0 이하면 만족0.37RC0.68KDS 140.80KDS 240.79ACI 150.67ACI 220.86AASHTO설계전단강도 ϕVn [kN]- - 점선: 현재 Vu = 150콘크리트 기여 + 스터럽 기여에 강도감소계수를 곱한 값410RC222KDS 14188KDS 24190ACI 15224ACI 22174AASHTO막대가 점선 위면 OK콘크리트 기여 Vc [kN]스터럽 없이 콘크리트만으로 버티는 전단력186RC93KDS 1488KDS 2491ACI 1595ACI 2286AASHTO스터럽 설계응력 [MPa]스터럽이 낼 수 있는 설계응력FRP는 굽힘부 강도에 걸림400RC225KDS 14180KDS 24180ACI 15225ACI 22180AASHTORC는 fyt , FRP는 fft (굽힘부 강도 제한)허용 스터럽 간격 sallow [mm]- - 점선: 현재 s = 150강도, 최소량, 상한 중 가장 작은 값이보다 촘촘해야 함254RC254KDS 14218KDS 24223ACI 15254ACI 22192AASHTO막대가 점선 위면 OK최소 전단보강 [mm²]붉은 짧은 선 = 그 기준의 한계강도상 필요 없어도 넣어야 하는 최소 스터럽 양52265RC93265KDS 14117265KDS 24117265ACI 1593265ACI 22117265AASHTO붉은 짧은 선 = 실제 배치량
항목RC, KDS 14 20 22KDS 14 20 68KDS 24 50 05ACI 440.1R-15ACI 440.11-22AASHTO GFRP 2018
예제 결과
$V_u = 150$ kN
$\phi V_n = \boxed{\mathbf{409.6}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.37}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
$\phi V_n = \boxed{\mathbf{221.7}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.68}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
$\phi V_n = \boxed{\mathbf{187.8}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.80}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
$\phi V_n = \boxed{\mathbf{189.8}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.79}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
$\phi V_n = \boxed{\mathbf{223.6}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.67}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
$\phi V_n = \boxed{\mathbf{173.9}\ \text{kN}}$
$V_u/\phi V_n = \mathbf{0.86}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$   $s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}$
설계 원칙
$\phi$
4.1.1 (4.1-1)
$$ V_u \le \phi V_n,\quad V_n = V_c + V_s $$
$\phi_v=0.75$
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_s) = 0.75\,(185.9 + 360.3) = \boxed{\mathbf{409.6}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{409.6} = \mathbf{0.37}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ \phi V_n \ge V_u,\quad V_n = V_c + V_f $$
$\phi_v=0.75$
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_f) = 0.75\,(92.9 + 202.7) = \boxed{\mathbf{221.7}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{221.7} = \mathbf{0.68}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
6.1, 6.2.1, 4.5 (6.1-1)(6.2-1)
$$ V_r=\phi V_n,\quad V_n = V_c + V_f $$
$\phi_v=0.75$
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_f) = 0.75\,(88.3 + 162.1) = \boxed{\mathbf{187.8}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{187.8} = \mathbf{0.80}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ \phi V_n \ge V_u,\quad V_n = V_c + V_f $$
$\phi=0.75$
↗ ACI 318 준용 (원문 미보유)
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_f) = 0.75\,(90.9 + 162.1) = \boxed{\mathbf{189.8}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{189.8} = \mathbf{0.79}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
22.5.1.1, 21.2 (22.5.1.1)
$$ V_n = V_c + V_f $$
$\phi=0.75$ (표 21.2.1)
단면 상한 (22.5.1.2) $V_u \le \phi\,0.2 f'_c b_w d$
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_f) = 0.75\,(95.5 + 202.7) = \boxed{\mathbf{223.6}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{223.6} = \mathbf{0.67}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}} \\ V_u &\le \phi\,0.2 f_{ck} b_w d = 0.75\times0.2\times30\times400\times509/10^3 = 916\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
2.7.3.3, 2.5.5.2 (2.7.3.3-1)
$$ V_n = V_c + V_f $$
$\phi=0.75$
$$\begin{aligned}\phi V_n &= 0.75\,(V_c + V_f) = 0.75\,(85.9 + 145.9) = \boxed{\mathbf{173.9}\ \text{kN}} \\ \frac{V_u}{\phi V_n} &= \frac{150}{173.9} = \mathbf{0.86}\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
콘크리트 전단강도
$V_c$
4.2.1 (4.2-1)(4.2-2)
$$ V_c=\frac{1}{6}\left(1+\frac{N_u}{14A_g}\right)\lambda\sqrt{f_{ck}}\,b_w d $$
축력 없으면 $(4.2\text{-}1)$
$$\begin{aligned}V_c &= \tfrac{1}{6}\Big(1+\tfrac{N_u}{14A_g}\Big)\lambda\sqrt{f_{ck}}\,b_w d \\ &= \tfrac{1}{6}\Big(1+\tfrac{0}{14\times240{,}000}\Big)(1.0)\sqrt{30}\times400\times509 \\ &= \boxed{\mathbf{185.9}\ \text{kN}}\end{aligned}$$
4.3.2 (4.3-1)–(4.3-3)
$$ V_c=\frac{1}{6}(1+k_p)\,k_s\,\beta_v\sqrt{f_{ck}}\,b_w d $$
$k_p=N_u/14A_g$
$k_s=(0.3/d)^{0.25}$ (0.75–1.1
최소보강 만족 시 1)
$\beta_v=0.5$ 독자식
$$\begin{aligned}k_p &= N_u/(14A_g) = 0/(14\times240{,}000) = 0.000 \\ k_s &= (0.3/d)^{0.25} = (0.3/0.509)^{0.25} = 0.88 \\ &\to [0.75,\,1.1] \to 0.88\ \to\ 1.00\ (\text{최소보강 만족}) \\ V_c &= \tfrac{1}{6}(1+0.000)(1.00)(\beta_v\,0.5)\sqrt{30}\times400\times509 = \boxed{\mathbf{92.9}\ \text{kN}}\end{aligned}$$
6.2.1(2) (6.2-2)
$$ V_c=\frac{2}{5}\sqrt{f_{ck}}\,b_w(kd) $$
$k$ = 균열단면 중립축비 (4.3-4)
$$\begin{aligned}n_f &= E_f/E_c = 45{,}000/27{,}537 = 1.63 \\ \rho_f &= A_f/(b_w d) = 3{,}040/(400\times509) = 0.0149 \\ k &= \sqrt{2\rho_f n_f+(\rho_f n_f)^2}-\rho_f n_f = 0.198 \\ kd &= 0.198\times509 = 100.7\ \text{mm} \\ V_c &= \tfrac{2}{5}\sqrt{30}\times400\times100.7 = \boxed{\mathbf{88.3}\ \text{kN}}\end{aligned}$$
8.2 (8.2a)(8.2b)
$$ V_c=\frac{2}{5}\sqrt{f'_c}\,b_w c,\quad k=\sqrt{2\rho_f n_f+(\rho_f n_f)^2}-\rho_f n_f $$
$c=kd$ (Tureyen & Frosch)
$$\begin{aligned}n_f &= E_f/E_c = 45{,}000/25{,}743 = 1.75 \\ \rho_f &= A_f/(b_w d) = 3{,}040/(400\times509) = 0.0149 \\ k &= \sqrt{2\rho_f n_f+(\rho_f n_f)^2}-\rho_f n_f = 0.204 \\ kd &= 0.204\times509 = 103.8\ \text{mm} \\ V_c &= \tfrac{2}{5}\sqrt{30}\times400\times103.8 = \boxed{\mathbf{90.9}\ \text{kN}}\end{aligned}$$
$$ V_c=\max\!\left(5\lambda_s k_{cr},\ 0.8\lambda_s\right)\sqrt{f'_c}\,b_w d\ \text{[psi]} \;\to\; \max(0.42\lambda_s k_{cr},\,0.066\lambda_s)\sqrt{f_{ck}}\,b_w d $$
크기효과 $\lambda_s=\sqrt{2/(1+0.004d)}\le1$ (최소보강 미만 시)
하한 $k_{cr}\ge0.16$ 상당
$$\begin{aligned}n_f &= E_f/E_c = 45{,}000/25{,}743 = 1.75 \\ \rho_f &= A_f/(b_w d) = 3{,}040/(400\times509) = 0.0149 \\ k &= \sqrt{2\rho_f n_f+(\rho_f n_f)^2}-\rho_f n_f = 0.204 \\ \lambda_s &= 1.00\ (A_{fv}\ge A_{fv,min}) \\ V_c &= \max(0.42k_{cr},\,0.066)\,\lambda_s\sqrt{f_{ck}}\,b_w d \\ &= \max(0.086,\,0.066)\times1.00\times\sqrt{30}\times400\times509 = \boxed{\mathbf{95.5}\ \text{kN}}\end{aligned}$$
2.7.3.4, 2.7.3.6.1 (2.7.3.4-1)
$$ V_c=0.0316\,\beta\sqrt{f'_c}\,b_v d_v\ \text{[ksi]},\quad \beta=5.0k,\ \theta=45^\circ $$
간이법 → SI $\tfrac{2}{5}k\sqrt{f_{ck}}\,b_v d_v$
$$\begin{aligned}n_f &= E_f/E_c = 45{,}000/25{,}743 = 1.75 \\ \rho_f &= A_f/(b_w d) = 3{,}040/(400\times509) = 0.0149 \\ k &= \sqrt{2\rho_f n_f+(\rho_f n_f)^2}-\rho_f n_f = 0.204 \\ d_v &= \max(0.9d,\,0.72h) = \max(458,\,432) = 458\ \text{mm} \\ V_c &= 0.42\,k\sqrt{f_{ck}}\,b_v d_v = 0.42\times0.204\times\sqrt{30}\times400\times458 \\ &= \boxed{\mathbf{85.9}\ \text{kN}}\end{aligned}$$
스터럽 전단강도
$V_s$, $V_f$, 상한
$$ V_s=\frac{A_v f_{yt} d}{s}\le\frac{2}{3}\lambda\sqrt{f_{ck}}\,b_w d $$
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_s &= \frac{A_v f_{yt} d}{s} = \frac{265\times400\times509}{150} = \boxed{\mathbf{360.3}\ \text{kN}} \\ V_{s,max} &= \tfrac{2}{3}\sqrt{30}\times400\times509 = 743.4\ \ge V_s\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
4.3.3.4(1), (4) (4.3-7)(4.3-10)
$$ V_f=\frac{A_{fv} f_{ft} d}{s}\le 0.25\,\xi_v f_{ck} b_w z,\quad \xi_v=0.6(1-f_{ck}/250),\ z=0.85d $$
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_f &= \frac{A_{fv} f_{ft} d}{s} = \frac{265\times225\times509}{150} = \boxed{\mathbf{202.7}\ \text{kN}} \\ V_{f,max} &= 0.25\,\xi_v f_{ck} b_w z = 0.25\times0.528\times30\times400\times433 = 685.3\ \ge V_f\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
6.2.1(4) (6.2-3)
$$ V_f=\frac{A_{fv} f_{fv} d}{s} $$
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_f &= \frac{A_{fv} f_{ft} d}{s} = \frac{265\times180\times509}{150} = \boxed{\mathbf{162.1}\ \text{kN}} \\ V_{f,max} &= 0.66\sqrt{30}\times400\times509 = 736.0\ \ge V_f\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
8.2, 8.2.3 (8.2c)
$$ V_f=\frac{A_{fv} f_{fv} d}{s},\quad V_f\le 8\sqrt{f'_c}\,b_w d\ [\text{psi}]=0.66\sqrt{f_{ck}}\,b_w d $$
8.2.3: ACI 318 상한 8√f′c 권장 (복부 압괴 0.18–0.3f′c 대신)
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_f &= \frac{A_{fv} f_{ft} d}{s} = \frac{265\times180\times509}{150} = \boxed{\mathbf{162.1}\ \text{kN}} \\ V_{f,max} &= 0.66\sqrt{30}\times400\times509 = 736.0\ \ge V_f\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
22.5.8.1, 22.5.8.5.3 (22.5.8.1)(22.5.8.5.3)
$$ V_f\ge\frac{V_u}{\phi}-V_c,\quad V_f=\frac{A_{fv} f_{ft} d}{s} $$
상한은 22.5.1.2 단면 제한으로
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_f &= \frac{A_{fv} f_{ft} d}{s} = \frac{265\times225\times509}{150} = \boxed{\mathbf{202.7}\ \text{kN}} \\ V_{f,max} &= 0.2 f_{ck} b_w d - V_c = 0.2\times30\times400\times509/10^3 - 95.5 = 1{,}126.1\ \ge V_f\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
2.7.3.5 (2.7.3.5-1)(2.7.2.5-1)
$$ V_f=\frac{A_{fv} f_{fv} d_v\cot\theta}{s}\le0.25\sqrt{f'_c}\,b_v d_v\ [\text{ksi}]=0.66\sqrt{f_{ck}}\,b_v d_v $$
$\theta=45^\circ$ → $\cot\theta=1$
$$\begin{aligned}A_v &= 2\times\pi\times13^2/4 = 265\ \text{mm}^2 \\ V_f &= \frac{A_{fv} f_{ft} d}{s} = \frac{265\times180\times458}{150} = \boxed{\mathbf{145.9}\ \text{kN}} \\ V_{f,max} &= 0.66\sqrt{30}\times400\times458 = 662.4\ \ge V_f\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
스터럽 설계응력
$$ f_{yt}\le 500\ \text{MPa} $$
$$\begin{aligned}f_{yt} &= 400\ \text{MPa} \le 500\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
4.3.3.4(2) (4.3-8)
$$ f_{ft}=0.005E_f\le f_{fb} $$
$f_{fb}$ = 굽힘부 설계기준인장강도 (앱: $(0.05r_b/d_b+0.3)f_{fu}$ 근사
직접 입력 가능)
$$\begin{aligned}f_{fb} &= (0.05\,r_b/d_b + 0.3)\,f_{fu} \\ &= (0.05\times3+0.3)\times850 = 382\ \text{MPa} \\ 0.005E_f &= 0.005\times45{,}000 = 225\ \text{MPa} \\ f_{ft} &= \min(225,\ 382) = \boxed{\mathbf{225}\ \text{MPa}}\end{aligned}$$
6.2.1(5) (6.2-4)
$$ f_{fv}=0.004E_f\le f_{fb} $$
$f_{fb}$ (3.2-6) $=(0.05r_b/d_b+0.3)f_{fu}$
$$\begin{aligned}f_{fb} &= (0.05\,r_b/d_b + 0.3)\,f_{fu} \\ &= (0.05\times3+0.3)\times800 = 360\ \text{MPa} \\ 0.004E_f &= 0.004\times45{,}000 = 180\ \text{MPa} \\ f_{ft} &= \min(180,\ 360) = \boxed{\mathbf{180}\ \text{MPa}}\end{aligned}$$
8.2, 6.2.1 (8.2d)(6.2.1)
$$ f_{fv}=0.004E_f\le f_{fb},\quad f_{fb}=\left(0.05\frac{r_b}{d_b}+0.3\right)f_{fu} $$
$$\begin{aligned}f_{fb} &= (0.05\,r_b/d_b + 0.3)\,f_{fu} \\ &= (0.05\times3+0.3)\times800 = 360\ \text{MPa} \\ 0.004E_f &= 0.004\times45{,}000 = 180\ \text{MPa} \\ f_{ft} &= \min(180,\ 360) = \boxed{\mathbf{180}\ \text{MPa}}\end{aligned}$$
$$ f_{ft}\le\min(f_{fb},\ 0.005E_f),\quad f_{fb}=C_E f_{fb}^* $$
0.005 (0.004 아님)
2026-08-28 원문 대조로 수정
$$\begin{aligned}f_{fb} &= (0.05\,r_b/d_b + 0.3)\,f_{fu} \\ &= (0.05\times3+0.3)\times850 = 382\ \text{MPa} \\ 0.005E_f &= 0.005\times45{,}000 = 225\ \text{MPa} \\ f_{ft} &= \min(225,\ 382) = \boxed{\mathbf{225}\ \text{MPa}}\end{aligned}$$
2.7.3.5 (2.7.3.5-2)(2.7.3.5-3)
$$ f_{fv}=0.004E_f\le f_{fb},\quad f_{fb}=\left(0.05\frac{r_b}{d_b}+0.3\right)f_{fd} $$
$$\begin{aligned}f_{fb} &= (0.05\,r_b/d_b + 0.3)\,f_{fu} \\ &= (0.05\times3+0.3)\times800 = 360\ \text{MPa} \\ 0.004E_f &= 0.004\times45{,}000 = 180\ \text{MPa} \\ f_{ft} &= \min(180,\ 360) = \boxed{\mathbf{180}\ \text{MPa}}\end{aligned}$$
소요 스터럽량
4.3.4 (4.3-3) 역산
$$ \frac{A_v}{s}=\frac{V_u-\phi V_c}{\phi f_{yt} d} $$
$$\begin{aligned}\phi V_c &= 0.75\times185.9 = 139.4 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-139.4)\times10^3}{0.75\times400\times509} \\ &= \boxed{\mathbf{0.069}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/0.069 = 3{,}823\ \text{mm}\end{aligned}$$
4.3.3.4(3) (4.3-9)
$$ \frac{A_{fv}}{s}=\frac{V_u-\phi V_c}{\phi f_{ft} d} $$
$$\begin{aligned}\phi V_c &= 0.75\times92.9 = 69.7 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-69.7)\times10^3}{0.75\times225\times509} \\ &= \boxed{\mathbf{0.935}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/0.935 = 284\ \text{mm}\end{aligned}$$
6.2.1(6) (6.2-5)
$$ \frac{A_{fv}}{s}=\frac{V_u-\phi V_c}{\phi f_{fv} d} $$
$$\begin{aligned}\phi V_c &= 0.75\times88.3 = 66.2 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-66.2)\times10^3}{0.75\times180\times509} \\ &= \boxed{\mathbf{1.220}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/1.220 = 218\ \text{mm}\end{aligned}$$
8.2 (8.2e)
$$ \frac{A_{fv}}{s}=\frac{V_u-\phi V_c}{\phi f_{fv} d} $$
$$\begin{aligned}\phi V_c &= 0.75\times90.9 = 68.2 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-68.2)\times10^3}{0.75\times180\times509} \\ &= \boxed{\mathbf{1.190}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/1.190 = 223\ \text{mm}\end{aligned}$$
22.5.8.1, R22.5.8.5 (22.5.8.1)(R22.5.8.5)
$$ \frac{A_{fv}}{s}=\frac{V_u-\phi V_c}{\phi f_{ft} d} $$
$$\begin{aligned}\phi V_c &= 0.75\times95.5 = 71.6 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-71.6)\times10^3}{0.75\times225\times509} \\ &= \boxed{\mathbf{0.913}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/0.913 = 291\ \text{mm}\end{aligned}$$
2.7.3.5 (2.7.3.5-1) 역산
$$ \frac{A_{fv}}{s}=\frac{V_u/\phi-V_c}{f_{fv} d_v} $$
$$\begin{aligned}\phi V_c &= 0.75\times85.9 = 64.5 < V_u = 150\ \to\ \text{스터럽 필요} \\ \frac{A_v}{s} &= \frac{V_u-\phi V_c}{\phi f d} = \frac{(150-64.5)\times10^3}{0.75\times180\times458} \\ &= \boxed{\mathbf{1.383}\ \text{mm²/mm}} \\ s_{req} &= A_v\big/\tfrac{A_v}{s} = 265/1.383 = 192\ \text{mm}\end{aligned}$$
최소 전단보강
$A_{v,min}$
4.3.3(3) (4.3-1)
$$ A_{v,min}=0.0625\sqrt{f_{ck}}\frac{b_w s}{f_{yt}}\ \ge\ 0.35\frac{b_w s}{f_{yt}} $$
$V_u > \tfrac{1}{2}\phi V_c$ 구간
$$\begin{aligned}A_{v,min} &= \max(0.0625\sqrt{30},\,0.35)\,\frac{b_w s}{f_{yt}} \\ &= \max(0.342,\,0.35)\times\frac{400\times150}{400} = \boxed{\mathbf{52}\ \text{mm²}} \\ A_v &= 265 \ge 52\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
4.3.3.3 (4.3-4)(4.3-5)
$$ A_{fv,min}=\max\!\left(0.0625\sqrt{f_{ck}},\ 0.35\right)\frac{b_w s}{f_{ft}} $$
$V_u \ge 0.5\phi V_c$ 구간
$$\begin{aligned}A_{fv,min} &= \max(0.0625\sqrt{30},\,0.35)\,\frac{b_w s}{f_{ft}} \\ &= 0.350\times\frac{400\times150}{225} = \boxed{\mathbf{93}\ \text{mm²}} \\ A_{fv} &= 265 \ge 93\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
6.2.2 (6.2-8)
$$ A_{fv,min}=0.35\frac{b_w s}{f_{fv}} $$
$V_u > \phi V_c/2$ 구간
$$\begin{aligned}A_{fv,min} &= 0.35\,\frac{b_w s}{f_{ft}} \\ &= 0.350\times\frac{400\times150}{180} = \boxed{\mathbf{117}\ \text{mm²}} \\ A_{fv} &= 265 \ge 117\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
8.2.2 (8.2.2)
$$ A_{fv,min}=0.35\frac{b_w s}{f_{fv}} $$
[50 $b_w s/f_{fv}$ psi]
$$\begin{aligned}A_{fv,min} &= 0.35\,\frac{b_w s}{f_{ft}} \\ &= 0.350\times\frac{400\times150}{180} = \boxed{\mathbf{117}\ \text{mm²}} \\ A_{fv} &= 265 \ge 117\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ A_{fv,min}=\max\!\left(0.75\sqrt{f'_c},\ 50\right)\frac{b_w s}{f_{ft}}\ \text{[psi]}\ \to\ \max(0.062\sqrt{f_{ck}},\,0.35)\frac{b_w s}{f_{ft}} $$
$V_u\ge\phi\,2.5k_{cr}\sqrt{f'_c}b_w\,d$ (= ½φV_c) 구간
$$\begin{aligned}A_{fv,min} &= \max(0.062\sqrt{30},\,0.35)\,\frac{b_w s}{f_{ft}} \\ &= 0.350\times\frac{400\times150}{225} = \boxed{\mathbf{93}\ \text{mm²}} \\ A_{fv} &= 265 \ge 93\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
2.7.2.4 (2.7.2.4-1)
$$ A_{fv}\ge0.05\frac{b_v s}{f_{fv}}\ \text{[ksi]}\ \to\ 0.35\frac{b_v s}{f_{fv}} $$
0.05 ksi = 0.345 MPa
2026-08-28 원문 대조로 수정(이전 0.083√$f_{ck}$ 오기)
$$\begin{aligned}A_{fv,min} &= 0.35\,\frac{b_w s}{f_{ft}} \\ &= 0.350\times\frac{400\times150}{180} = \boxed{\mathbf{117}\ \text{mm²}} \\ A_{fv} &= 265 \ge 117\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
간격 제한
$s_{max}$
$$ s\le d/2,\ 600\ \text{mm} $$
$V_s>\tfrac{1}{3}\lambda\sqrt{f_{ck}}b_w\,d$ 이면 절반
$$\begin{aligned}s_{max} &= \min(d/2,\,600) = \min(254,\,600) = 254\ \text{mm} \\ V_s &= 360.3 \le \tfrac{1}{3}\sqrt{f_{ck}}\,b_w d = 371.7\ \to\ \text{절반 규정 미적용} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(3{,}823,\,758,\,254) \\ &= \boxed{\mathbf{254}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ s\le d/2,\ 600\ \text{mm} $$
KDS 14 20 22 4.3.2 준용 (단 4.3.2(2) 제외)
$$\begin{aligned}s_{max} &= \min(d/2,\,600) = \min(254,\,600) = 254\ \text{mm} \\ V_f &= 202.7 \le \tfrac{1}{3}\sqrt{f_{ck}}\,b_w d = 371.7\ \to\ \text{절반 규정 미적용} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(284,\,427,\,254) \\ &= \boxed{\mathbf{254}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ s\le d/2,\ 600\ \text{mm} $$
6.3(2) $r_b/d_b\ge3$
(3) 90° 갈고리 꼬리 $12d_b$
$$\begin{aligned}s_{max} &= \min(d/2,\,600) = \min(254,\,600) = 254\ \text{mm} \\ V_f &= 162.1 \le \tfrac{1}{3}\sqrt{f_{ck}}\,b_w d = 371.7\ \to\ \text{절반 규정 미적용} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(218,\,341,\,254) \\ &= \boxed{\mathbf{218}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ s\le d/2,\ 600\ \text{mm (24 in.)} $$
절반 규정은 ACI 318 준용(앱: $V_f>\tfrac{1}{3}\sqrt{f_{ck}}b_w\,d$ 이면 d/4
300)
$$\begin{aligned}s_{max} &= \min(d/2,\,600) = \min(254,\,600) = 254\ \text{mm} \\ V_f &= 162.1 \le \tfrac{1}{3}\sqrt{f_{ck}}\,b_w d = 371.7\ \to\ \text{절반 규정 미적용} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(223,\,341,\,254) \\ &= \boxed{\mathbf{223}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
9.7.6.2.2 표 9.7.6.2.2
$$ V_f\le4\sqrt{f'_c}b_w\,d:\ s\le d/2,\ 24\ \text{in};\qquad V_f>4\sqrt{f'_c}b_w\,d:\ s\le d/4,\ 12\ \text{in} $$
SI: $4\sqrt{f'_c}=0.33\sqrt{f_{ck}}$
600/300 mm
$$\begin{aligned}s_{max} &= \min(d/2,\,600) = \min(254,\,600) = 254\ \text{mm} \\ V_f &= 202.7 \le \tfrac{1}{3}\sqrt{f_{ck}}\,b_w d = 371.7\ \to\ \text{절반 규정 미적용} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(291,\,427,\,254) \\ &= \boxed{\mathbf{254}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
$$ s\le0.5d,\ 600\ \text{mm (24 in.)} $$
절반 규정 없음
2026-08-28 원문 대조로 수정(이전 0.8d_v/0.4d_v 오기)
$$\begin{aligned}s_{max} &= \min(0.5d,\,600) = \min(254,\,600) = 254\ \text{mm} \\ s_{allow} &= \min(s_{req},\,s_{min},\,s_{max}) = \min(192,\,341,\,254) \\ &= \boxed{\mathbf{192}\ \text{mm}} \ \ge s = 150\ \ \color{#0a8a2a}{\checkmark\ \textbf{OK}}\end{aligned}$$
환경감소계수
$C_E$ (참고)
해당 없음
RC 해당 없음
$$ C_E=0.85 $$
노출환경 무관 (GFRP)
$$\begin{aligned}f_{fu} &= C_E\,f_{fu}^* = 0.85\times1000 = \boxed{\mathbf{850}\ \text{MPa}}\end{aligned}$$
$$ C_E=0.8\ /\ 0.7 $$
비노출 / 노출 (GFRP)
$$\begin{aligned}f_{fu} &= C_E\,f_{fu}^* = 0.80\times1000 = \boxed{\mathbf{800}\ \text{MPa}}\end{aligned}$$
$$ C_E=\begin{cases}\text{GFRP }0.8/0.7\\ \text{CFRP }1.0/0.9\\ \text{AFRP }0.9/0.8\end{cases} $$
섬유 종류 × 노출
$$\begin{aligned}f_{fu} &= C_E\,f_{fu}^* = 0.80\times1000 = \boxed{\mathbf{800}\ \text{MPa}}\end{aligned}$$
$$ C_E=0.85 $$
노출 무관
ASTM D7957 내구성 요건
$$\begin{aligned}f_{fu} &= C_E\,f_{fu}^* = 0.85\times1000 = \boxed{\mathbf{850}\ \text{MPa}}\end{aligned}$$
$$ C_E=0.8\ /\ 0.7 $$
비노출 / 노출 (GFRP)
$$\begin{aligned}f_{fu} &= C_E\,f_{fu}^* = 0.80\times1000 = \boxed{\mathbf{800}\ \text{MPa}}\end{aligned}$$
이 앱의 검증 근거
손계산 대조 ($V_{c}$ 185.9, φV_n 409.7, $A_{v}$/s 0.069, s 255)
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)
공식 예제 없음 → (4.3-1) 손계산, 화면값 손검산 (verify_engine.py)
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)
공식 예제 없음 → 식 대조 (6.2-2)–(6.2-8)
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)
설계예제 8M (SI) 대조: k, φV_c, $f_{fb}$, $f_{fv}$, $A_{fv}$/s, 간격 3종 2% 이내 통과
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)
스캔 원문 눈대조 (21.2, 20.2.2.3, 2.2.6, 표 22.5.5.1, 22.5.8.1, 8.5.3, 9.6.3.1, 3.4, 9.7.6.2.2) → 식 반영. SI 계수(0.42, 0.066, 0.062)는 psi→MPa 환산
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)
스캔 원문 눈대조 (2.4.2.1, 2.5.5.2, 2.7.2.4, 2.5, 2.6, 2.8, 2.7.3.3–3.6.1) → 간이법(β=5k, θ=45°) 반영. 일반법(MCFT 2.7.3.6.2) 미구현
✔ 2차 독립구현 무작위 300케이스 × 6항목 대조 일치 (verify_shear_independent.py, 0.2%)