Page 165 - สะพานเครื่องหนุนมั่น

7-7

ตารางที่ 7.3 convenient Approximate Equivalences

Units

Quantity
USCS SI Exact Si approx.

Length 1 in. 25.4 mm 25 mm
1 ft 0.3048 m 0.3 m

Mass 1 lb(mass) 0.4536 kg 0.5 kg
2
2
2
Area 1 ft 0.09290 m 0.1 m
3
3
3
Volume 1 yd 0.765 m 0.75 m .
Force 1 lb 4.448 N 4.5 N
1 kip 4.448 kN 4.5 kN.
1 lb/ft 14.59 N/m 15 N/m
1 kip/ft 14.59 kN/m 15 kN/m

-
.
Moment 1 ft -lb 1.356 N m 1.4 N m
.
.
1 ft -kip 1.356 kN m 1.4 kN m
Pressure 1 psi 6.895 kPa 7 kpa
1 psf 47.88 48 Pa
Some Typical values:

3
3
3
Water density 62.4 lb/ft 1000 kg/m 1000 kg/m
3
3
3
concrete density 150 lb/ft 2402.81 kg/m 2400 kg/m
3
3
3
Water (Weight/Volume) 62.4 lb/m 9.81 kN /m 10 kn/m
3
3
3
Concrete ( " ) 150 p/ft 23576 N/m 24 kN/m
Concrete stress 3000 psi 20.67 MPa 21 MPa
Steel Stress 25,000 psi 172.38 MPa 170 MPa
6
E steel 29 x 10 psi 199.9 GPa 200GPa
6
E Concrete 3.5 x10 psi 24.13 GPa 24 GPa