Research methods: For argument about this view point writer took three reinforced concrete bridges in her country as engineering background:(1) During construction, crack of one main span 40 m+65 m+40m prestressed concrete continuous beam bridge was found on main pier of the bridge. (2)During construction, some cracks of one large span reinforced concrete half-through highway arch bridge with both stringer and horizontal girder system were found on these horizontal girders.(3)The main beam anchor outline of one twin beams cable-stayed bridge in the south China area was changed. By 8-point isoperimetric element spatial analysis of Super SAP software, these local models were separately setup and we can carry on stress calculation as well as.