|220.127.116.11 Slab-like steel parts on a flatrack|
Inadequate cargo securing methods and poor workmanship mean that these slab-like parts are not sufficiently secured.
Only the lowermost part is secured in the lengthwise direction. The upper three parts can move freely in the lengthwise direction. None of the parts is secured in the sideways direction as sufficient securing forces cannot be applied even with several tie-down lashings.
Too few wire clips have been used. Some of them have also be placed on the wrong side. Spacing between the clamps is inadequate. The tightening moment is too low.
Only if four wire clips are correctly applied and properly tightened can the maximum securing load of the wire ropes and turnbuckles be fully utilized.
Only approx. one quarter of the height of the squared lumber is actually effective, so that not only is little strength obtained, but much material is wasted too.
Untidy workmanship has meant that short lengths of board have had to be inserted to fill the gaps in the squared lumber structure. The maximum securing load can be calculated from the contact area of the small board with the squared lumber and loading capacity perpendicular to the grain of 30 daN/cm². Without the board, the loading capacity would have been calculated in the case of a neat arrangement on the basis of the contact area of the squared lumber with the end wall of the flatrack with loading capacity parallel to the grain of 100 daN/cm², which would have produced a distinctly higher value.
The parts could have been provided with lateral securing relatively simply by using loop lashings. Their number is determined by the anticipated shipping stresses, the lashing materials used and how they are applied together with any materials laid beneath or between the layers.
In this case too, bracing with wooden members is an effective way of providing lengthwise securing. The loop lashings providing lateral securing have not been including in this drawing.
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