Multi-axial stresses in intermittent rail welds

For light to medium-heavy crane loads the rails are often attached to the crane runway by intermittent longitudinal rail welds. An intermittent rail weld offers advantages in many aspects and is often used in practice. For the fatigue verification though, only the detail of the intermittent weld between the flange and web of an I-section in Table 8.2, EN 1993-1-9 (1) can be used as a reference resulting in detail category 80 for longitudinal direct stresses in the flange. However, the shear stress is only considered indirectly, as described in (2). The transverse stresses from the wheel load, though, are not considered at all.
In the research project (2), this detail has been investigated experimentally and numerically. The re-sults led to an amendment for the prEN1993-6 (3). Part of these investigations were fatigue experi-ments on 3.5 m long girders with intermittent rail welds. The rail welds were stressed in 6 four-point bending tests by longitudinal stresses only and in another 6 three-point bending tests with additional transverse stresses due to the wheel load. These tests had a stationary load, further 6 tests were run under a traveling load by the research partners at the Materials Testing Institute of the University of Stuttgart. The stationary experiments and the findings also in view of numerical studies are described and explained in this paper.