cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
LET’S ANALYZE THIS BEAM WITH ONE SPAN AND TWO CANTILEVERS
As it is not symmetrical, the vertical reaction forces at A and B
are not going to be equal
B C
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
B C
B C
TO SIMPLIFY THE PROBLEM WE CAN TRANSFORM THE
CANTILEVERS IN END MOMENTS AT THE SUPPORTS:
TO CALCULATE THE REACTION FORCES
WE CAN EQUILIBRATE EACH FORCE AND
MOMENT AND ADD THE RESULTS:
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
ONCE WE KNOW THE VERTICAL
REACTION FORCES VALUES,
WE CAN DRAW THE SHEAR
FORCE DIAGRAM
AND THE BENDING MOMENT
DIAGRAM
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
TO CALCULATE THE DEFLECTION IN THE MIDDLE OF THE SPAN WE CAN APPLY
THE FORMULAS FOR SIMPLE BEAMS
B C
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE DISTRIBUTED LOAD
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam exampleEFFECT OF THE PUNCTUAL LOAD
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE MOMENT AT THE LEFT END
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE MOMENT AT THE RIGHT END
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
𝑣 𝑞 = −
5 ⋅ 𝑞 ⋅ 𝐿4
384 ⋅ 𝐸𝐼
𝑣2𝑃 = −
2𝑃 ⋅ 𝐿3
48 ⋅ 𝐸𝐼
𝑣 𝑀𝑙𝑒𝑓𝑡 =
𝑀𝑙𝑒𝑓𝑡 ⋅ 𝐿2
16 ⋅ 𝐸𝐼
𝑣 𝑀𝑟𝑖𝑔ℎ𝑡 =
𝑀𝑟𝑖𝑔ℎ𝑡 ⋅ 𝐿2
16 ⋅ 𝐸𝐼
DEFLECTION IN THE MIDDLE OF THE SPAN
V total = vq + vP + vMleft + vMright = -10,68 mm
Beam bending stiffness: EI = 10000 kNm2
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
TO CALCULATE THE ROTATION AT B WE CAN APPLY AGAIN
THE SIMPLE BEAM FORMULAS
B C
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE DISTRIBUTED LOAD
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE PUNCTUAL LOAD
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE MOMENT AT THE LEFT END
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
EFFECT OF THE MOMENT AT THE RIGHT END
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
𝑔𝐵𝑞 = −
𝑞 ⋅ 𝐿3
24 ⋅ 𝐸𝐼
𝑔𝐵2𝑃 = −
2𝑃 ⋅ 𝐿2
16 ⋅ 𝐸𝐼
𝑔𝐵 𝑀𝑙𝑒𝑓𝑡 =
𝑀𝑙𝑒𝑓𝑡 ⋅ 𝐿
3 ⋅ 𝐸𝐼
𝑔𝐵 𝑀𝑟𝑖𝑔ℎ𝑡 =
𝑀𝑟𝑖𝑔ℎ𝑡 ⋅ 𝐿
6 ⋅ 𝐸𝐼
B C
gB total = gBq + gBP + gB Mleft + gB Mright = -4,275 mrad
Beam bending stiffness: EI = 10000 kNm2
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
𝑣𝐿𝑒𝑓𝑡 𝑞 = −
𝑞 ⋅ 𝐿4
8 ⋅ 𝐸𝐼
𝑣𝐿𝑒𝑓𝑡 𝑃 = −
𝑃 ⋅ 𝐿3
3 ⋅ 𝐸𝐼
𝑣𝐿𝑒𝑓𝑡 𝑔𝐵 = 𝑔𝐵 ⋅ 𝐿𝑙𝑒𝑓𝑡
TO CALCULATE THE VERTICAL DISPLACEMENT AT THE END OF THE CANTILEVER
WE MUST CONSIDER THE EFFECT OF THE CANTILEVER PLUS THE EFFECT OF THE
ROTATION AT B (already known)
V total = vq + vP + gB x Lcantilever = -0,5 mm
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam exampleEFFECT OF THE MOMENT LOADS ALONG THE CANTILEVER
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
𝑔𝐷 𝑞 = −
𝑞 ⋅ 𝐿3
24 ⋅ 𝐸𝐼
𝑔𝐷2𝑃 = −
2𝑃 ⋅ 𝐿2
16 ⋅ 𝐸𝐼
𝑔𝐷 𝑀𝑙𝑒𝑓𝑡 =
𝑀𝑙𝑒𝑓𝑡 ⋅ 𝐿
6 ⋅ 𝐸𝐼
𝑔𝐷 𝑀𝑟𝑖𝑔ℎ𝑡 =
𝑀𝑟𝑖𝑔ℎ𝑡 ⋅ 𝐿
3 ⋅ 𝐸𝐼
ROTATION AT D (ROLLER)
WE REPEAT THE PROCCESS FOR THE RIGHT CANTILEVER
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example
𝑣𝑅𝑖𝑔ℎ𝑡 𝑞 = −
𝑞 ⋅ 𝐿4
8 ⋅ 𝐸𝐼
𝑣𝑅𝑖𝑔ℎ𝑡 𝑔𝐷 = 𝑔𝐵 ⋅ 𝐿𝑙𝑒𝑓𝑡
VERTICAL DISPLACEMENT AT THE END OF THE CANTILEVER
WE REPEAT THE PROCCESS FOR THE RIGHT CANTILEVER
V total = vq + vP + gD x Lcantilever = +9,5 mm
cperez.eps@ceu.es
molina.eps@ceu.es
STRUCTURAL ANALYSIS I
DEGREE IN ARCHITECTURE
Year 3 Term 1
simple beam example

Ae1 19 20_1_beam with cantilvers