Nowadays, steel bridge members are inspected through shop assembly in factory yard at the final process of their fabrication. This investigation proposes an inspection system which excludes the process of shop assembly. To realize this system, however, precise knowledge concerning the accuracy of fablication and assembly is indispensable.
For this reason, main members of a plate girder and a composite girder were measured and data about the accuracy of assembly were gathered. This report studies the relationship between errors of memberes and the accuracy of shop assembly. Such data have never been obtained by conventional inspections. As a result, it was confirmed that members are fabricated precisely enough not to induce any stresses in assembling them. This result will contribute to the development of good inspection systems.