Design ultimate loads

The components should be loaded to the design service load or to failure. Loading to the design ultimate load may be relevant for compliance testing, see 7.2.2, but gives no information on the safety factors associated with collapse. 

CORRESPONDING ELASTIC-PLASTIC MODEL FOR DESIGN ULTIMATE LOADS... 

Corresponding elastic-plastic model for design ultimate loads... 

Flexural member design requires the determination of (1) the design blast loads, (2) the initial design cross-section, (3) an idealized resistance deflection function, (4) the calculated response (maximum deflection) and, (5) allowable ultimate deflection and (6) design for shear. 

Post-installed bolts will be required at times for attachment of equipment which may be subjected to large accelerations during a blast. Expansion anchors should be avoided for most blast design applications unless the load levels are low. Typically "wedge" type anchors are qualified for dynamic loads although most of these ratings are for vibratory loads and are based on cyclic tests at low stress levels. These should only be used where ultimate loads are less than the rated capacity with a margin of safely. Epoxy anchors have shown excellent dynamic capacity and may be considered for critical applications. 

In a strict sense, an advanced analysis" is one in which the nonlinear geometric and material effects are accounted for in the analysts of the structure as a whole in determining its ultimate load carrying capacity. In addition, effects of local as well as overall global instability are considered such that it is not necessary to evaluate individual members subsequent to the completion of the advanced analysts. In other words, all the appropriate limit state, design code requirements are incorporated into the analysts (White 1993, Chen 1994). 

This ultimate moment of resistance is greater than the design moment of 378 kN m and the section is, therefore, satisfactory for this ultimate limit state. However, it has to be checked for the stresses in the serviceability limit state. As for the ultimate load method, the second moment of area of the composite section is 7.01 x 10 mm and the elastic modulus of the steel beam alone is 949 cm , and thus the stage 1 steel beam stress is... 

Failure Compensation indicates the measures through which the failure can be compensated, eg. Design by adequate resCTve factor (ratio strength/ultimate load), replacement of units, redundant system. 

Figure 5.31 Ultimate load-bearing capacity of a bonded joint (A Failure) and the load-bearing capacity utilised according to the design procedure (A Design)-...

Loading to the design ultimate, or a multiple thereof, will give confidence that the connections in the complete structure are capable of performing satisfactorily. Unless a linear behaviour up to collapse of the connection can be assumed, such tests give little indication of the ultimate margin of safety. However, they confirm that premature adhesive failure will not occur. 

The strength reduction method and the criterion of cusp catastrophe curve method for assessing the ultimate load has satisfied the development of computer aided analysis. The wide study and application of this method will be considered as a more powerful alternative to traditional methods, and it will help design an effective and relatively economical foundation solution. 

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