Ans: It depends on the friction factor input in the dialog of the saddles between the sliding saddles and the concrete or the plate under the sliding saddles. A small friction factor value indicates that a PTFE plate or in some cases rolling bars have been installed. The values of the longitudinal loads (RaHL) are calculated as follow: No. Support saddles Location (mm) Stiffness (daN/mm) Vertical Horizontal Combined Reactions (daN) Shear Loads (daN) Bending moments (daN∙m) Reactions Transverse (daN) Shear Loads (daN) Bending moments (daN∙m) Reactions Longitudinal (daN) Reactions (daN) Shear Loads (daN) Bending moments (daN∙m) 1 500.0 2,716.2 -324.1 2,392.2 -144.2 -2,424.7 0.0 0.0 0.0 2,402.7 2,716.2 -324.1 2,392.2 -144.2 -2,424.7 2 4,500.0 4,190.7 -1,623.1 2,567.7 -2,245.8 -697.1 0.0 0.0 0.0 -1,629.2 4,190.7 -1,623.1 2,567.7 -2,245.8 -697.1 3 8,500.0 2,057.6 -1,433.9 623.8 -1,134.0 -744.0 0.0 0.0 0.0 -521.1 2,057.6 -1,433.9 623.8 -1,134.0 -744.0 4 11,500.0 673.9 -349.8 324.1 -333.5 -144.2 0.0 0.0 0.0 -252.4 673.9 -349.8 324.1 -333.5 -144.2 The fixed saddle is located in this example on the left hand. How are the RaHL values calculated? Run the model with a friction factor equal to 0 and you will obtain the values of vertical reaction loads used for the calculation of RaHL (as shown here after): No. Support saddles Location (mm) Stiffness (daN/mm) Vertical Horizontal Combined Reactions (daN) Shear Loads (daN) Bending moments (daN∙m) Reactions Transverse (daN) Shear Loads (daN) Bending moments (daN∙m) Reactions Longitudinal (daN) Reactions (daN) Shear Loads (daN) Bending moments (daN∙m) 1 500.0 2,162.0 -324.1 1,837.9 -144.5 0.0 0.0 0.0 0.0 2,162.0 -324.1 1,837.9 -144.5 2 4,500.0 5,253.1 -2,177.3 3,075.8 -2,181.7 0.0 0.0 0.0 0.0 5,253.1 -2,177.3 3,075.8 -2,181.7 3 8,500.0 1,559.4 -925.8 633.7 -585.1 0.0 0.0 0.0 0.0 1,559.4 -925.8 633.7 -585.1 4 11,500.0 664.0 -339.9 324.1 -144.5 0.0 0.0 0.0 0.0 664.0 -339.9 324.1 -144.5 In this example, the mass of the each saddle is 181 kg (177.4 daN). The friction factor is equal to 0.3 The loads on the sliding saddles are equal to: W2ini = 5253.1 + 177.4 = 5430.5 daN RaHL2 = 5430.5 x 0.3 = 1629.2 daN W3ini = 1559.4 + 177.4 = 1736.8 daN RaHL3 = 1736.8 x 0.3 = 521.1 daN W4ini = 664 + 177.4 = 841.4 daN RaHL4 = 841.4 x 0.3 = 252.4 daN The sign is – for these loads. The system is on equilibrium è S RaHL = 0 The load on the fixed saddle is equal to: RaHL1 = 1629.2 + 521.1 + 252.4 = 2402.7 daN When the longitudinal loads exist, the vertical loads are modified. These modified values are due to the moments
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