Page 468 - Design of Reinforced Masonry Structures
P. 468

7.30                      CHAPTER SEVEN

                Pier 3:
                            h   6
                              =    = 09 .
                                .
                            d  667
                                   ⎛ ⎡
                                    h ⎞
                                1
                           ∆ 3  =  Et ⎝ ⎠  3  3 ⎛ ⎝  h ⎞  ⎤ ⎥ ⎦
                                   ⎜ ⎟ + ⎜ ⎟ ⎥
                                  ⎢
                                           d ⎠
                                    d
                                m ⎣
                              =     1    [( 09 . ) 3  + 3 09 . )]
                                                 (
                               ( 1800 7 625)
                                   )( .

                                      −4
                                   (
                                .
                              = 2 498 10 )in.
                                       )
                            R =  1  =  1    =  4003 kips/in .
                               ∆  3  . 2 498 (10  )
                             3            4 −
                Pier 4:
                      h    6
                       =      = 1 125
                                .
                      d  5 333
                          .
                              ⎛ ⎡
                                      h ⎞ ⎤
                                  3
                                     ⎛
                                h ⎞
                     ∆  =  1  = ⎜ ⎟ + ⎜ ⎟ ⎥
                              ⎢
                                    3
                      4
                         Et   ⎣ ⎣ ⎝ d ⎠  ⎝ d ⎠ ⎦
                          m
                       =      1     [( .  3  +3 1 125)]
                                            ( .
                                     1 125)
                         (1800 )(7 625 )
                                .
                                4 −
                       = 3.4496 10(  )in.

                     R  =  1  =  1    =  2860 kips/inn.
                         ∆   3 496 10 )
                      4             4 −
                                 (
                              .
                          4
                    R wall  = R  + R  + R  = 2407 + 4003 + 2860 = 9270 kips/in.
                              3
                          2
                                 4
                Method B: Calculate the deflection of the entire wall assuming it as a solid can-
                tilever. Ignore all openings.
                          h  16
                            =  = 0 4444
                                  .
                          d  36
                              1  ⎡  ⎛  h ⎞  3  ⎛ h ⎞ ⎤
                         ∆  =   ⎢ ⎢ 4 ⎜ ⎟ + ⎜ ⎟ ⎥
                                        3
                          3
                             Et   ⎝ d ⎠  ⎝ d ⎠ ⎦
                              m ⎣
                             ( 1800 7 625)
                            =     1    [( .    3  + 3 0 4444)]
                                        4 0 4444)
                                                  ( .
                                 )( .
                                     4 −
                                  (
                            =1 2271 10 )in.
                             1.
                Calculate the deflection of the solid strip containing the tallest opening (com-
                bined piers 2, 3, 4, and 5) assuming it as fixed-ended.
                               h  10
                                 =  = 0 2778
                                       .
                               d  36
                                         3
                                             ⎛ ⎞ ⎤
                                       h ⎞
                                              h
                      ∆          =  1  ⎢ ⎛ ⎡ ⎜ ⎟ + ⎜ ⎟ ⎥
                                            3
                       solidstrip  234  Et ⎝ ⎠ ⎠  ⎝ ⎠ ⎦
                            ++ +5
                                   m ⎣
                                       d
                                              d
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