Answer:
1) 1.4(D + F)
2) 1.2(D + F + T) + 1.6(L + H) + 0.5(Lr or S or R)
3) 1.2D + 1.6(Lr or S or R) + ((0.5 or 1.0)*L or 0.8W)
4) 1.2D + 1.6W + (0.5 or 1.0)*L + 0.5(Lr or S or R)
5) 1.2D + 1.0E + (0.5 or 1.0)*L + 0.2S
6) 0.9D + 1.6W + 1.6H
7) 0.9D + 1.0E + 1.6H
Explanation:
Load and Resistance Factor Design
there are 7 basic load combination of LRFD that is
1) 1.4(D + F)
2) 1.2(D + F + T) + 1.6(L + H) + 0.5(Lr or S or R)
3) 1.2D + 1.6(Lr or S or R) + ((0.5 or 1.0)*L or 0.8W)
4) 1.2D + 1.6W + (0.5 or 1.0)*L + 0.5(Lr or S or R)
5) 1.2D + 1.0E + (0.5 or 1.0)*L + 0.2S
6) 0.9D + 1.6W + 1.6H
7) 0.9D + 1.0E + 1.6H
and
here load factor for L given ( * ) mean it is permitted = 0.5 for occupancies when live load is less than or equal to 100 psf
here
D is dead load and L is live load
E is earth quake load and S is snow load
W is wind load and R is rain load
Lr is roof live load
Answer:
diameter is 14 mm
Explanation:
given data
power = 15 kW
rotation N = 1750 rpm
factor of safety = 3
to find out
minimum diameter
solution
we will apply here power formula to find T that is
power = 2π×N×T / 60 .................1
put here value
15 ×
= 2π×1750×T / 60
so
T = 81.84 Nm
and
torsion = T / Z ..........2
here Z is section modulus i.e = πd³/ 16
so from equation 2
torsion = 81.84 / πd³/ 16
so torsion = 416.75 / / d³ .................3
so from shear stress theory
torsion = σy / factor of safety
so here σy = 530 for 1020 steel
so
torsion = σy / factor of safety
416.75 / d³ = 530 × 
/ 3
so d = 0.0133 m
so diameter is 14 mm
Answer:
if you are speaking of the acronym then Engineering uses science and mathematics to solve everyday problems in society
Harmonic excitation refers to a sinusoidal external force of a certain frequency applied to a system. ... Resonance occurs when the external excitation has the same frequency as the natural frequency of the system. It leads to large displacements and can cause a system to exceed its elastic range and fail structurally.
