I have also had this issue. The IFCs were authored in Revit.
I believe it is due to large co-ordinates.In my case I noticed that the centres of the bounding boxes in the web viewer were aligned, rather than being at the correct relative placements.
A workaround is to manually edit the IFC file in a text editor to move the IFCSite coordinate system back to (or close to) the origin (applying the same displacement for each file).
Hopefully Trimble are working on a proper solution.