The shear Shear check is based on AASHTO Article 5.8.6, entitled Shear and Torsion for Segmental Box Girder Bridges.The shear check design torsion for segmental box girder bridges. The shear design-check request provides the following results:

• Controlling Demand/Capacity Ratio
• Shear Rebar Area/Length
• Torsion Rebar Area/Length
• Shear + Torsion Area/Length
• Longitudinal Rebar Area - demand-capacity ratio
• Shear rebar area and length
• Torsion rebar area and length
• Shear and torsion area and length
• Longitudinal rebar area (shear causes tension in longitudinal reinforcement (- see AASHTO LRFD 2007, C5.8.3.5)

Web

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shear force and resistance

Shear force and shear resistance are idealized to act along web height. Capacity is proportional to area. Components relate forces in the reference frame to those within an inclined web. Web force is found by magnifying the vertical force by 1/cos(α) by a truss analogy to get the force along the web. However, since we are actually reporting in the vertical direction rather than along the web, we instead reduce the capacity . Similarly, vertical force is derived by reducing web force by cos(α). This is basically saying that an inclined web is not as good at resisting vertical shear as is a vertical web of having the same areaGiven this relationship, an element web most effectively resists vertical shear when oriented vertically.