Bridge diaphragm FAQ
This page is devoted to frequently asked questions (FAQ) related to bridge diaphragms.
On this page:
What is the brace work point?
Extended Question: Regarding chord and brace diaphragm type, what is the brace work point and how is its elevation determined?
Answer: The brace work point is a point where the centroid of a horizontal chord member intersects the centroid of an inclined brace member. The elevation is user-defined and measured from either the top or bottom of the chord web.
How is diaphragm location and orientation specified?
Answer: When diaphragms are defined for individual girder bays (ie. the diaphragms are not full width diaphragms), the diaphragm location is measured along the girder from the start of the girder within the given span. Due to tolerance issues, the program may not place diaphragms that are too close the bearing line or would intersect the bearing line. You can to resolve this by specifying absolute value for the diaphragm bearing or by slightly adjusting the location of the diaphragm. If this still does not help, you can still draw the diaphragm members manually, not as a part of the bridge object.