To hokie 66,
Thanks for your response and your interest on the subject. It is interesting to learn how structural failures happen. However, I would say that rather than performing an investigation, I have been trying to gain some insight on the failure and, in connection with that, how to prevent that failure to happen again, and how that bridge could be reconstructed (or how it should not be reconstructed).
The attachment to my original message shows the condition of the south anchorages before failure. I am attaching now a picture of the north anchorages. You will notice a difference. In the north anchorage the three steel bars at each cable appear to be on the same plane. In the south anchorage, one of the bars is out of the plane of the other two. Force diagrams at the node of the connection show that the load on the bar out of plane can be as high, or even higher than the tension in the cable, depending on the alignment of the cable relative to the bars, see attachment. This may have been a construction error. The over load on that bar may have caused the failure.
I have not been able to get a picture of the failed anchors (I am thousands of miles from San Juan del Sur). Pictures from digital editions of the local papers have very poor resolution, but it seems that the cables were disengaged from the anchors. It seems that the failure happened at the "eye" of the anchors, not on the straight leg of the anchor. Did the bar break at the eye? Did the weld attaching the two legs of the loop failed?
In any case, the type of anchors they used seems very fragile and highly vulnerable to misalignment. The bridge should not be reconstructed using the anchors of the north end, even if they didn't fail.
By the way, how do I transfer this thread to the structural section?