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Beam Three Support Four Loads Equations and Calculator

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Beam Three Support four Loads, Moments, Shear and Reactions Equations and Calculator

Continuous beam of two equal spans - four concentrated loads, P, at third points of each span Calculator

Continuous beam of two equal spans
Figure 1 Continuous beam of two equal spans

Preview: Beam Three Support Two Loads Calculator

Reactions:

Eq. 1
R1 = (2/3) P

Eq. 2
R2 = (8/3) P

Eq. 3
R3 = (2/3) P

Shear forces:

Eq. 4
V1 = (2/3) P

Eq. 5
V2 = ±(4/3) P

Eq. 6
V3 = - (2/3) P

Bending moments:

Eq. 7
Mmax = -(1/3) P L , at R2

Eq. 8
M1 = (2/9) P L, at point of load

Eq. 9
M2 = (1/9) P L, at point of load

Where

P = concentrated load, lbf (N)
L = beam length, in, (m)
R1, 2, 3 = reaction at support , lbf (N)
V1, 2, 3 = shear forces lbf, (N)
M1, 2, max = bending moments, lb-in, (N-m)

Related

Source

Civil Engineering Reference Manual, Fifteenth Edition, Michael R. Lindeburg, PE