If this is the centre section of a 10m ling beam and we assume a uniformly distributed membrane force acting in the interface between the edge beam and slab it will be 8* Mz/L2 = 45kN/m and will be compressive.Ĭlick ✓ OK to close the Bending, Axial and Shear form. The associated Mz moment is -561.1kNm but this bending will be restrained by the membrane action in the adjoining slab. The limiting additional load is now 503.9kNm. The neutral angle axis is 35.2°.Ĭlick on the Neutral Axis angle drop down menu and select “Fixed horizontal” from the list. The limiting additional load is 174.01kNm. Ensure that Analysis type is set to “ULS Persistent/Transient”.Ĭlick on the Loadcase drop down menu and select “SL1: Loadcase” from the list.Ĭlick on the Resistance drop down menu and select “Y Moment – Positive” from the list.Ĭlick on the Neutral Axis angle drop down menu and select “Free” from the list.
Use the toolbar button dropdown in the Design Section navigation window to select “Bending Axial & Shear” which will open the Bending, Axial and Shear form. On the first row of the table, click in the Type column and select “Y Moment” from the drop down list.Įnter a value of “218kNm” in the Characteristic Effect column.Įnter a value of “1.35” in the Ultimate | γ column.Ĭlick ✓ OK to close the Define loads form. which will open the Define Loadcase form.Ĭlick on the other “+” button near the bottom of the form to add a row to the table. Use the toolbar button at the top of the Design Section navigation window to create a new loadcase. Set the Bridge Type to be “Road” from the dropdown list. This is done on the Section Overview form which can be accessed from the File | Section Overview. To do this the correct bridge type must be assigned to the section. Define Applied Forcesįor bridge structures it is possible to define the various components of load effects to assemble a valid EN 1990 combination with automatically applied load and psi factors. Repeat steps 10 and 11 for the top right hand corner.Ĭlick ✓ OK to close the Define Reinforcement form. Both faces will be highlighted in red and the Locate bar by 2 covers form will open.Įnter values of “50mm” in both the Cover to face 1 and Cover to face 2 fields then click ✓ OK of faces field and enter a value of “2” (the default cover of 50mm is assumed) then click ✓ OKĬlick on the Generate drop down menu and select “1 bar by 2 covers” from the list.Ĭlick in the Diameter field and enter a value of “16mm”.Ĭlick on the left hand vertical and the top curved faces of the section on the graphics window. The face will be highlighted in red and the Reinforcement along face(s) form will open.Ĭlick in the No. Of bars field and enter a value of “7”.Ĭlick in the Diameter field and enter a value of “25mm”.Ĭlick on the sloping bottom face of the section on the graphics window. Open the Define Reinforcement form by clicking on the “Reinforcement” object in the Design Section navigation windowĬlick on the Generate drop down menu and select “Reinforce Face(s)” from the list.Ĭlick in the No. Use the menu item File | Titles to change the Section Title to “Grillage Edge Section with Reinforcement”, the Sub-title to “Example 3.4a” and the Job Number to “3.4a”. Start the program and use the menu item File | Open to open the file “EU Example 2_1.sam” created in section 2.1 of this manual. What links of 10mm diameter are required? At what value of shear force will it be necessary to have additional links? The design moments and forces at ULS are My = 350kNm, Axial = 1320kN, Shear along z = 180kN. What is the maximum additional characteristic My moment that can be applied at ULS. This column has a characteristic concentric axial load of 1000kN together with a characteristic Mz moment of 100kNm. What is the value of this force if the beam is 10m long? Save this section for use in other examples. What is the My ULS capacity now? By keeping the neutral axis horizontal there is an out of balance Mz moment which is resisted by a transverse membrane force in the slab. What is the angle of the neutral axis? The precast beam is stitched to a continuous insitu slab which forces the neutral axis to be horizontal. Check that the My ULS capacity of the section exceeds this. The precast beam is lifted at its ends through the centroid of the section which generates a nominal My bending moment of 218kNm due to its self weight (Gamma ULS = 1.35).
16mm bars are placed in the top of the upstand with 50mm cover to both faces.
The end bars have 50mm cover to the vertical faces.
25mm bars in the bottom faces with 50mm cover. Ultimate limit state section capacities, for moments and axial force, are to be calculated for two of the sections defined in section 2 as follows: Precast Section
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