Challenge

Project 1

`Lundersetx/Lundersety` = 9/3 = 3>2 therefore is a ONE WAY SLAB

1. WITHOUT LOAD PATTERNING

STEP 1

LOADS FROM SLAB

1. SW of slab

t = 120mm = 0.120m

= unit weight of cncrete x 0.120m

= 25kN/m3 x 0.120m

  1. SW = 3kN/m2
  2. LL = 5kPa = 5kN/m2
  3. SDL = 3kPa = 3kN/m2
  4. TL = SW+ DL + LL = 3 + 5 + 3 = 11 kN/m2

STEP 2

LOAD FROM SLAB TO BEAM

= 11 `(kN)/m^2` x (9x1.5) `m^2`

= 11x 13.5

= 148.5kN

= 148.5kN/ 9m

= 16.5 `(kN)/m`

since load from slab gets transmitted from both sides

= 16.5 x 2

= 33 kN/m

STEP 3

SW OF BEAM

= unit wt of concrete x area of c/s of beam

= 25 `(kN)/m^3` x 0.5m x 0.75m

= 9.375kN/m

STEP 4

TOTAL LOAD ON BEAM

= 33 + 9.375

= 42.375kN/m

STEP 5

SOLVING BEAM USING SLOPE DEFLECTION METHOD

TO FIND FIXED END MOMENTS

`Munderset(FAB)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FBA)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FBC)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FCB)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FCD)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FDC)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FDE)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FED)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

STEP 5

SUPPORT END MOMENT

`Munderset(AB) = Munderset(FAB) + 4EIthetaundersetA/L + 2EIthetaundersetB/L`

`Munderset(AB) = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`0 = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`286.031 - 2EIthetaundersetB/9 = 4EIthetaundersetA/9`

`2EIthetaundersetA/9 = 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = Munderset(FBA) + 4EIthetaundersetB/L + 2EIthetaundersetA/L`

`Munderset(BA) = 286.031 + 4EIthetaundersetB/9 + 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = 429.0465 + 3EIthetaundersetB/9`

`Munderset(BC) = Munderset(FBC) + 4EIthetaundersetB/L + 2EIthetaundersetC/L`

`Munderset(BC) = -286.031 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`Munderset(CB) = Munderset(FCB) + 4EIthetaundersetC/L + 2EIthetaundersetB/L`

`Munderset(CB) = 286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9`

`Munderset(CD) = Munderset(FCD) + 4EIthetaundersetC/L + 2EIthetaundersetD/L`

`Munderset(CD) = -286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`Munderset(DC) = Munderset(FDC) + 4EIthetaundersetD/L + 2EIthetaundersetC/L`

`Munderset(DC) = 286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`

`Munderset(DE) = Munderset(FDE) + 4EIthetaundersetD/L + 2EIthetaundersetE/L`

`Munderset(DE) = -286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetE/9`

`Munderset(ED) = Munderset(FED) + 4EIthetaundersetE/L + 2EIthetaundersetD/L`

`0 = 286.031 + 4EIthetaundersetE/9 + 2EIthetaundersetD/9`

`4EIthetaundersetE/9 = -286.031 - 2EIthetaundersetD/9`

`2EIthetaundersetE/9 = -143.0155 - EIthetaundersetD/9`

`sum MundersetB` =0,

`Munderset (BA) + Munderset(BC)` = 0

`429.0465 + 3EIthetaundersetB/9`` -286.031 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`143.0155+ 7EIthetaundersetB/9 + 2EIthetaundersetC/9` =0

`7EIthetaundersetB/9 + 2EIthetaundersetC/9` = -143.0155 ... (1)

`sum MundersetC` =0,

`Munderset (CB) + Munderset(CD)` = 0

`286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9``-286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`2EIthetaundersetB/9 + 8EIthetaundersetC/9 + 2EIthetaundersetD/9` =0 ... (2)

`sum MundersetD` =0,

`Munderset (DC) + Munderset(DE)` = 0

`286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`` -286.031 + 4EIthetaundersetD/9 -143.0155 - EIthetaundersetD/9 `

`-143.0155+ 7EIthetaundersetD/9 + 2EIthetaundersetC/9` =0

`2EIthetaundersetC/9 + 7EIthetaundersetD/9` = 143.0155 ... (3)

`[[7/9,2/9,0,|,EIthetab],[2/9,8/9,2/9,|,EIthetac],[0,2/9,7/9,|,EIthetad]]` = `((-143.0155),(0),(143.0155))`

R2`->`R1 - 3.5 R2

`[[7/9,2/9,0,|,EIthetab],[0,-26/9,-7/9,|,EIthetac],[0,2/9,7/9,|,EIthetad]]` = `((-143.0155),(-143.0155),(143.0155))`

R3`->`13 R3 + R2

`[[7/9,2/9,0,|,EIthetab],[0,-26/9,-7/9,|,EIthetac],[0, 0 ,84/9,|,EIthetad]]` = `((-143.0155),(-143.0155),(1716.186))`

`EIthetaunderset(D)`= 183.8770

`EIthetaunderset(C)`= 0

`EIthetaunderset(B)`= -183.8770

`EIthetaunderset(E)`= -735.5083

`EIthetaunderset(A)`= 735.5083

Substituting the above values we get

`Munderset(AB) = 0`

`Munderset(BA) = 367.754 kNm`

`Munderset(BC) = -367.754 kNm`

`Munderset(CB) = 245.169 kNm`

`Munderset(CD) = -245.169 kNm`

`Munderset(DC) = 367.757 kNm`

`Munderset(DE) = -367.757 kNm`

`Munderset(ED) = 0`

2. WITH LOAD PATTERNING

LL always varies therefore is never 100% full in a building , so based on its occupancy using Muller Breslau's principle its location are determined to find max positive and negative bending moment

STEP 1

LOADS FROM SLAB

1. SW of slab

t = 120mm = 0.120m

= unit weight of cncrete x 0.120m

= 25kN/m3 x 0.120m

  1. SW = 3kN/m2
  2. LL = 5kPa = 5kN/m2
  3. SDL = 3kPa = 3kN/m2
  4. TL = SW+ DL + LL = 3 + 5 + 3 = 11 kN/m2

STEP 2

LOAD FROM SLAB TO BEAM

= 11 `(kN)/m^2` x (9x1.5) `m^2`

= 11x 13.5

= 148.5kN

= 148.5kN/ 9m

= 16.5 `(kN)/m`

since load from slab gets transmitted from both sides

= 16.5 x 2

= 33 kN/m

STEP 3

SW OF BEAM

= unit wt of concrete x area of c/s of beam

= 25 `(kN)/m^3` x 0.5m x 0.75m

= 9.375kN/m

STEP 4

TOTAL LOAD ON BEAM

= 33 + 9.375

= 42.375kN/m

PLACES WITHOUT LL

STEP 1

LOADS FROM SLAB

1. SW of slab

t = 120mm = 0.120m

= unit weight of cncrete x 0.120m

= 25kN/m3 x 0.120m

  1. SW = 3kN/m2
  2. SDL = 3kPa = 3kN/m2
  3. TL = SW+ DL = 3 + 3 = 6 kN/m2

STEP 2

LOAD FROM SLAB TO BEAM

= 6 `(kN)/m^2` x (9x1.5) `m^2`

= 6x 13.5

= 81kN

= 81kN/ 9m

= 9`(kN)/m`

since load from slab gets transmitted from both sides

= 9 x 2

= 18 kN/m

STEP 3

SW OF BEAM

= unit wt of concrete x area of c/s of beam

= 25 `(kN)/m^3` x 0.5m x 0.75m

= 9.375kN/m

STEP 4

TOTAL LOAD ON BEAM

= 18 + 9.375

= 27.375kN/m

(a) TO FIND MAX BENDING MOMENT AT D

STEP 5

SOLVING BEAM USING SLOPE DEFLECTION METHOD

TO FIND FIXED END MOMENTS

`Munderset(FAB)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FBA)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FBC)` = `-(wl^2)/12` = `-( 27.375 xx 9^2)/12` = -184.78kNm

`Munderset(FCB)` = `(wl^2)/12` = `( 27.375 xx 9^2)/12` = 184.78kNm

`Munderset(FCD)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FDC)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FDE)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FED)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

STEP 5

SUPPORT END MOMENT

`Munderset(AB) = Munderset(FAB) + 4EIthetaundersetA/L + 2EIthetaundersetB/L`

`Munderset(AB) = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`0 = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`286.031 - 2EIthetaundersetB/9 = 4EIthetaundersetA/9`

`2EIthetaundersetA/9 = 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = Munderset(FBA) + 4EIthetaundersetB/L + 2EIthetaundersetA/L`

`Munderset(BA) = 286.031 + 4EIthetaundersetB/9 + 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = 429.0465 + 3EIthetaundersetB/9`

`Munderset(BC) = Munderset(FBC) + 4EIthetaundersetB/L + 2EIthetaundersetC/L`

`Munderset(BC) = -184.78 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`Munderset(CB) = Munderset(FCB) + 4EIthetaundersetC/L + 2EIthetaundersetB/L`

`Munderset(CB) = 184.78 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9`

`Munderset(CD) = Munderset(FCD) + 4EIthetaundersetC/L + 2EIthetaundersetD/L`

`Munderset(CD) = -286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`Munderset(DC) = Munderset(FDC) + 4EIthetaundersetD/L + 2EIthetaundersetC/L`

`Munderset(DC) = 286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`

`Munderset(DE) = Munderset(FDE) + 4EIthetaundersetD/L + 2EIthetaundersetE/L`

`Munderset(DE) = -286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetE/9`

`Munderset(ED) = Munderset(FED) + 4EIthetaundersetE/L + 2EIthetaundersetD/L`

`0 = 286.031 + 4EIthetaundersetE/9 + 2EIthetaundersetD/9`

`4EIthetaundersetE/9 = -286.031 - 2EIthetaundersetD/9`

`2EIthetaundersetE/9 = -143.0155 - EIthetaundersetD/9`

`sum MundersetB` =0,

`Munderset (BA) + Munderset(BC)` = 0

`429.0465 + 3EIthetaundersetB/9`` -184.78 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`244.266+ 7EIthetaundersetB/9 + 2EIthetaundersetC/9` =0

`7EIthetaundersetB/9 + 2EIthetaundersetC/9` = -244.266 ... (1)

`sum MundersetC` =0,

`Munderset (CB) + Munderset(CD)` = 0

`-286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9``184.78 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`2EIthetaundersetB/9 + 8EIthetaundersetC/9 + 2EIthetaundersetD/9` = 101.251 ... (2)

`sum MundersetD` =0,

`Munderset (DC) + Munderset(DE)` = 0

`286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`` -429.0465+ 4EIthetaundersetD/9 -143.0155 - EIthetaundersetD/9 `

`-143.0155+ 7EIthetaundersetD/9 + 2EIthetaundersetC/9` =0

`2EIthetaundersetC/9 + 7EIthetaundersetD/9` = 143.0155 ... (3)

`[[7/9,2/9,0],[2/9,8/9,2/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` =`((-244.266),(101.251),(143.0155))``

R2`->`3.5 R2 - R1

`[[7/9,2/9,0],[0,26/9,7/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((-244.266),(598.645),(143.015))`

R3`->`13 R3 - R2

`[[7/9,2/9,0],[0,26/9,7/9],[0, 0 ,84/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((-244.266),(598.645),(1260.55))`

`EIthetaunderset(D)`= 135.058

`EIthetaunderset(C)`= 170.861

`EIthetaunderset(B)`= -362.873

Substituting the above values we get

`Munderset(DC) = 384.025 kNm`

`Munderset(DE) = -384.025 kNm`

(b) TO FIND BENDING MOMENT AT B

Following similar procedure

Since structure and loads are symmetrical

`Munderset(BA) = 384.025 kNm`

`Munderset(BC) = -384.025 kNm`

(c) TO FIND MAX BENDING MOMENT AT C

STEP 5

SOLVING BEAM USING SLOPE DEFLECTION METHOD

TO FIND FIXED END MOMENTS

`Munderset(FAB)` = `-(wl^2)/12` = `-( 27.375 xx 9^2)/12` = - 184.781kNm

`Munderset(FBA)` = `(wl^2)/12` = `( 27.375 xx 9^2)/12` = 184.781kNm

`Munderset(FBC)` = `-(wl^2)/12` = `-( 18.375 xx 9^2)/12` = -124.03kNm

`Munderset(FCB)` = `(wl^2)/12` = `( 18.375 xx 9^2)/12` = 124.03kNm

`Munderset(FCD)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FDC)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FDE)` = `-(wl^2)/12` = `-( 27.375 xx 9^2)/12` = - 184.781kNm

`Munderset(FED)` = `(wl^2)/12` = `( 27.375 xx 9^2)/12` = 184.781kNm

STEP 5

SUPPORT END MOMENT

`Munderset(AB) = Munderset(FAB) + 4EIthetaundersetA/L + 2EIthetaundersetB/L`

`Munderset(AB) = -184.781 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`0 = -184.781 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`184.781 - 2EIthetaundersetB/9 = 4EIthetaundersetA/9`

`2EIthetaundersetA/9 = 92.3905 - EIthetaundersetB/9`

`Munderset(BA) = Munderset(FBA) + 4EIthetaundersetB/L + 2EIthetaundersetA/L`

`Munderset(BA) = 184.781 + 4EIthetaundersetB/9 + 92.3905 - EIthetaundersetB/9`

`Munderset(BA) = 277.172 + 3EIthetaundersetB/9`

`Munderset(BC) = Munderset(FBC) + 4EIthetaundersetB/L + 2EIthetaundersetC/L`

`Munderset(BC) = -286.031 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`Munderset(CB) = Munderset(FCB) + 4EIthetaundersetC/L + 2EIthetaundersetB/L`

`Munderset(CB) = 286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9`

`Munderset(CD) = Munderset(FCD) + 4EIthetaundersetC/L + 2EIthetaundersetD/L`

`Munderset(CD) = -286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`Munderset(DC) = Munderset(FDC) + 4EIthetaundersetD/L + 2EIthetaundersetC/L`

`Munderset(DC) = 286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`

`Munderset(DE) = Munderset(FDE) + 4EIthetaundersetD/L + 2EIthetaundersetE/L`

`Munderset(DE) = -184.781 + 4EIthetaundersetD/9 + 2EIthetaundersetE/9`

`Munderset(ED) = Munderset(FED) + 4EIthetaundersetE/L + 2EIthetaundersetD/L`

`0 = 184.781 + 4EIthetaundersetE/9 + 2EIthetaundersetD/9`

`4EIthetaundersetE/9 = -184.781 - 2EIthetaundersetD/9`

`2EIthetaundersetE/9 = -92.3905 - EIthetaundersetD/9`

`sum MundersetB` =0,

`Munderset (BA) + Munderset(BC)` = 0

`7EIthetaundersetB/9 + 2EIthetaundersetC/9` = 8.859 ... (1)

`sum MundersetC` =0,

`Munderset (CB) + Munderset(CD)` = 0

`2EIthetaundersetB/9 + 8EIthetaundersetC/9 + 2EIthetaundersetD/9` = 0 ... (2)

`sum MundersetD` =0,

`Munderset (DC) + Munderset(DE)` = 0

`2EIthetaundersetC/9 + 7EIthetaundersetD/9` = -8.86 ... (3)

`[[7/9,2/9,0],[2/9,8/9,2/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` =`((8.859),(0),(-8.859))`

R2`->`3.5 R2 - R1

`[[7/9,2/9,0],[0,26/9,7/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((8.859),(-8.859),(-8.859))`

R3`->`13 R3 - R2

`[[7/9,2/9,0],[0,26/9,7/9],[0, 0 ,84/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((8.859),(-8.859),(-124.026))`

`EIthetaunderset(D)`= -13.288

`EIthetaunderset(C)`= 0.5109

`EIthetaunderset(B)`= 11.244

Substituting the above values we get

`Munderset(CB) = 288.757 kNm`

`Munderset(CD) = -288.757 kNm`

(d) TO FIND BM AT MID SPAN OF BEAM

STEP 5

SOLVING BEAM USING SLOPE DEFLECTION METHOD

TO FIND FIXED END MOMENTS

`Munderset(FAB)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FBA)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FBC)` = `-(wl^2)/12` = `-( 27.375 xx 9^2)/12` = -184.78kNm

`Munderset(FCB)` = `(wl^2)/12` = `( 27.375 xx 9^2)/12` = 184.78kNm

`Munderset(FCD)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 286.031kNm

`Munderset(FDC)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 286.031kNm

`Munderset(FDE)` = `-(wl^2)/12` = `-( 42.375 xx 9^2)/12` = - 184.781kNm

`Munderset(FED)` = `(wl^2)/12` = `( 42.375 xx 9^2)/12` = 184.781kNm

STEP 5

SUPPORT END MOMENT

`Munderset(AB) = Munderset(FAB) + 4EIthetaundersetA/L + 2EIthetaundersetB/L`

`Munderset(AB) = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`0 = -286.031 + 4EIthetaundersetA/9 + 2EIthetaundersetB/9`

`286.031 - 2EIthetaundersetB/9 = 4EIthetaundersetA/9`

`2EIthetaundersetA/9 = 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = Munderset(FBA) + 4EIthetaundersetB/L + 2EIthetaundersetA/L`

`Munderset(BA) = 286.031 + 4EIthetaundersetB/9 + 143.0155 - EIthetaundersetB/9`

`Munderset(BA) = 429.0465 + 3EIthetaundersetB/9`

`Munderset(BC) = Munderset(FBC) + 4EIthetaundersetB/L + 2EIthetaundersetC/L`

`Munderset(BC) = -184.78 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`Munderset(CB) = Munderset(FCB) + 4EIthetaundersetC/L + 2EIthetaundersetB/L`

`Munderset(CB) = 184.78 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9`

`Munderset(CD) = Munderset(FCD) + 4EIthetaundersetC/L + 2EIthetaundersetD/L`

`Munderset(CD) = -286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`Munderset(DC) = Munderset(FDC) + 4EIthetaundersetD/L + 2EIthetaundersetC/L`

`Munderset(DC) = 286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`

`Munderset(DE) = Munderset(FDE) + 4EIthetaundersetD/L + 2EIthetaundersetE/L`

`Munderset(DE) = -184.781 + 4EIthetaundersetD/9 + 2EIthetaundersetE/9`

`Munderset(ED) = Munderset(FED) + 4EIthetaundersetE/L + 2EIthetaundersetD/L`

`0 = 184.781 + 4EIthetaundersetE/9 + 2EIthetaundersetD/9`

`4EIthetaundersetE/9 = -184.781 - 2EIthetaundersetD/9`

`2EIthetaundersetE/9 = -92.3905 - EIthetaundersetD/9`

`sum MundersetB` =0,

`Munderset (BA) + Munderset(BC)` = 0

`429.0465 + 3EIthetaundersetB/9`` -184.78 + 4EIthetaundersetB/9 + 2EIthetaundersetC/9`

`244.266+ 7EIthetaundersetB/9 + 2EIthetaundersetC/9` =0

`7EIthetaundersetB/9 + 2EIthetaundersetC/9` = -244.266 ... (1)

`sum MundersetC` =0,

`Munderset (CB) + Munderset(CD)` = 0

`-286.031 + 4EIthetaundersetC/9 + 2EIthetaundersetB/9``184.78 + 4EIthetaundersetC/9 + 2EIthetaundersetD/9`

`2EIthetaundersetB/9 + 8EIthetaundersetC/9 + 2EIthetaundersetD/9` = 101.251 ... (2)

`sum MundersetD` =0,

`Munderset (DC) + Munderset(DE)` = 0

`286.031 + 4EIthetaundersetD/9 + 2EIthetaundersetC/9`` -182.781+ 4EIthetaundersetD/9 -143.0155 - EIthetaundersetD/9 `

`8.8595+ 7EIthetaundersetD/9 + 2EIthetaundersetC/9` =0

`2EIthetaundersetC/9 + 7EIthetaundersetD/9` = -8.8595 ... (3)

`[[7/9,2/9,0],[2/9,8/9,2/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` =`((-244.266),(101.251),(-8.8595))``

R2`->`3.5 R2 - R1

`[[7/9,2/9,0],[0,26/9,7/9],[0,2/9,7/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((-244.266),(598.645),(-8.8595))`

R3`->`13 R3 - R2

`[[7/9,2/9,0],[0,26/9,7/9],[0, 0 ,84/9]]` `((EIthetaa),(EIthetab),(EIthetac))` = `((-244.266),(598.645),(-483.456))`

`EIthetaunderset(D)`= -51.802

`EIthetaunderset(C)`= 221.175

`EIthetaunderset(B)`= -377.273

`sumMunderset(BA)` =0,

`Munderset(BA)` - 42.375x9x9/2 + `RundersetA`x9 =0

Ra= 156.988 kN

`Munderset(@mid AB)`

= Ra(4.5) - 42.375 (4.5x4.5/2)

`Munderset(@mid AB) = 277.399 kNm`

Similarly at other mid spans

the mid span sagging moment at each span = 277.399kNm

(e) TO FIND MAX POSITIVE BENDING MOMENT FOR EVERY SPAN

The max. Bending moment occurs where the shear force becomes zero.

Ra - w x X = 0

156.988 - 42.375(x) = 0

156.988 = 42.375x

x=3.7m

`Munderset(3.5m A)` from A

= Ra(3.7) - 42.375(3.7x3.7/2)

= 156.988(3.7) - (42.375)(3.7x3.7/2)

= 290.798kNm

SIMILARLY FOR EVERY SPAN

= 290.798kNm

(since structure and loads are symmetrical and load patterning to find max positive or sagging moment is placing udl on alternate beams.)

1. WITHOUT LOAD PATTERNING

MAXIMUM NEGATIVE MOMENTS

Mmax @ B = 367.754kNm (hogging)

Mmax @ C = 245.169kNm (hogging)

Mmax @ D = 367.754kNm (hogging)

2. WITH LOAD PATTERNING

MAXIMUM NEGATIVE MOMENTS

Mmax @ B = 384.025kNm (hogging)

Mmax @ C = 288.757kNm (hogging)

Mmax @ D = 384.025kNm (hogging)

MAXIMUM POSITIVE MOMENTS

Mmax @ for everyspan = 290.798kNm (sagging)

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