You have a typical bolted joint, with lots of bolts, loaded by forces and moments ... Well what can be used for it ? VDI guideline 2230, perhaps?
Apart from many shortcomings, the very title "Systematic calculation of high duty bolted joints, Joint with one cylindrical bolt " says: "NO!"
You want to know, why is the application of VDI 2230 in your case not only inappropriate but maybe also dangerous?
To increase efficiency through ultra-supercritical steam conditions of coal and gas power stations (which should replace the at lower temperatures functioning nuclear power plants), for thermal protection of aerospace structures, fuel cells, solar concentration panels and Stirling engines applications.
Increasing the operating temperatures in this regard is a significant challenge to materials technology
Based on the improvement of the classical strain range partitioning method
Significant creep strains result with hold times and time-dependent stress change. The not balanced within one cycle creep yields either CP or PC partitions, where the PC shares, as a result of oxidation, influences the life stronger.
The effect of oxidation can be introduced in the calculation of the cyclic life through the time-temperature substitution (similar to the creep). On the occasion it should be noted in particular that the oxidation very strongly accelerated the formation of cracks on the surface
With far advanced creep damage in the material volume the subsequent crack propagation is also considerably accelerates
The simple accumulation of fatigue and creep portions of the damage may significantly underestimate these combined effects.
To meet increasing competition, get products to market in the shortest possible time, and satisfy customer expectations, traditional test methods are no longer sufficient.
The need to observe failures of products to better understand their failure modes and their life characteristics, design practitioners have attempted to devise methods to force these products to fail more quickly than they would under normal use conditions.
Fracture mechanics is now widely applied in order to demonstrate that the components of the system, despite the inevitable small errors in the material structure, are suitable for the application ("fitness for purpose").
With the stress-strain method proposed by the author, no premature reduction in LEFM regime is developed and the reduction in the plastic region is determined by the increased intensity of strains in a critical section. That corresponds not only to the observed behaviour but it is also in full compliance with the energy-based criteria that prevail in fracture mechanics.
The new method is approved for the application on the most critical thin-walled components with surface defects, which are characterized by their total area. Typical uneven distribution of relevant variables (K, J) along the contour of the surface cracks will be balanced during the failure in ductile materials. Increased accuracy of the method both below and above the yield strength in comparison to existing methods (R-6, FAD, etc.) avoids the unnecessary conservatism in design of this for the applications most important area.
Traditionally, most designs are based on previous experiences and similar implementations with some modifications introduced to fulfil particular requirements. Starting from it, the designer is trying to make a best judgment concerning the expected behaviour of the new structure on the basis of information and examinations of the constructions realized and tried already. Application of such procedure in the case of the fibre-reinforced ceramic materials (CMC) can lead to serious mistakes.
It is known that the cases of the trust-rockets (booster) for the Space Shuttle and ARIANE 5, that produce approximately 80% of the power of the system, are assembled together from several cylindrical segments using the so-called Clevis-Tang connection.
Accident, which has led to the explosion of the Challenger, was caused by the failure of the Clevis-Tang-connection at right booster. Because of this, this connection was examined especially thoroughly within of the ARIANE 5 development. The selected concept differs significantly opposite of the so-called improved space Shuttle solution and was additionally optimized to reduce the total weight of the case.
Should the nuclear power be cut off today, tomorrow, or at least the day after tomorrow? Although this question seems actual at present it is misleading in certain respects. Because, cut off does not mean dangers averted! It still produced a lot of heat (5-10% of the previous thermal power), which must be dissipated. Because the energy for the power supply is removed, the nuclear power plants, even though this amount of energy decreases significantly over time, become electricity consumers, for several years.
At this time, the "burned" fuel elements are very hot and highly radioactive, so that they can be only remotely controlled and behind protective shields, were got from the reactor with the help of robots into the so-called cooling ponds, where they are then several years and cooled.
If the cooling system for some reason does not work properly threatens a meltdown (Fukushima). The danger of meltdown, that you if happens most of it cannot stop, continuously exist ... ...
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