ISO 8686-1:2012 pdf download.Cranes - Design principles for loads and load combinations— Part 1: General.
6.1.5 Loads induced by displacements
Account shall be taken of loads arising from displacements included In the design, such as those resulting from pre-stressing and those within the limits necessary to initiate response of skewing and other compensating control systems.
Other loads to be considered include those that can arise from displacements that are within defined limits, such as those set for the variation in the gauge between rails or uneven settlement of supports.
6.2 Occasional loads
6.2.1 Climatic effects
Loads due Lu In-service wind shall be calculated In accordance with ISO 4302.
6.2.1.2 Snow and ice loads
Where relevant, snow and ice loads shall be taken into account. The increased wind exposure surfaces due to encrustat Ion shall be considered.
6.2.1.3 Loads due to temperature variation
Loads caused by the restraint of expansion or contraction of a component due to local temperature variation shall be taken into account.
6.2.2 Loads caused by skewing
This subclause covers skewing loads that occur at the guidance means (such as guide rollers or wheel flanges) of a guided, wheel-mounted crane while it is travelling or traversing in steady-state motion. These loads are induced by guidance reactions which force the wheels to deviate from their frec• rolling, natural travelling direction. Simila r loads, induced by acceleration acting on asymmetrical mass distribution and that can also cause the crane to skew, are taken into account under 6.1.4.
Skewing loads as defined above are usually taken as occasional loads but their frequency of occurrence varies with the type, configuration, accuracies of wheel axle parallelism and service of the crane. In individual cases, the frequency of occurrence will determine whether they arc taken as occasional or regular loads.
NOTE Guidance for establishing the magnitude of skewing Loads and the category into which they are placed for a specifIc crane type is given In those parts of ISO 8686 covering specific types of cranes.
Account shall be taken of loads arising from displacements included In the design, such as those resulting from pre-stressing and those within the limits necessary to initiate response of skewing and other compensating control systems.
Other loads to be considered include those that can arise from displacements that are within defined limits, such as those set for the variation in the gauge between rails or uneven settlement of supports.
6.2 Occasional loads
6.2.1 Climatic effects
Loads due Lu In-service wind shall be calculated In accordance with ISO 4302.
6.2.1.2 Snow and ice loads
Where relevant, snow and ice loads shall be taken into account. The increased wind exposure surfaces due to encrustat Ion shall be considered.
6.2.1.3 Loads due to temperature variation
Loads caused by the restraint of expansion or contraction of a component due to local temperature variation shall be taken into account.
6.2.2 Loads caused by skewing
This subclause covers skewing loads that occur at the guidance means (such as guide rollers or wheel flanges) of a guided, wheel-mounted crane while it is travelling or traversing in steady-state motion. These loads are induced by guidance reactions which force the wheels to deviate from their frec• rolling, natural travelling direction. Simila r loads, induced by acceleration acting on asymmetrical mass distribution and that can also cause the crane to skew, are taken into account under 6.1.4.
Skewing loads as defined above are usually taken as occasional loads but their frequency of occurrence varies with the type, configuration, accuracies of wheel axle parallelism and service of the crane. In individual cases, the frequency of occurrence will determine whether they arc taken as occasional or regular loads.
NOTE Guidance for establishing the magnitude of skewing Loads and the category into which they are placed for a specifIc crane type is given In those parts of ISO 8686 covering specific types of cranes.
