Extreme-Wind Risk Assessment

First step towards preventing losses due to mechanical damage from abnormal actions: Knowledge-based forecasting the actions

“…2; the fragment is considered to be a material point in these coordinates Comments on the model: expression of the injection velocity m 13 ðz 3 j p 3 Þ was adopted from Baker (1983), the values m 23 ðz 3 ; t j p 3 Þ and m 33 ðz 3 ; t j p 3 Þ are computed for given t by a numerical integration of the coupled ODEs; these ODEs were formulated under the assumption that the fragment will tumble during its motion; the ODEs are widely used to predict a motion of bodies which are described as material points (Baker, 1983;Twisdale & Vickery, 1993), assigning and updating the d.f. F P 3 ðp 3 jp P 3 Þ are discussed in Table 3 Phenomenon under consideration: hitting the building by the fragment Random event related to the phenomenon: not used Model related to the phenomenon: m 4 ðz 4 j p 4 Þ Destination of the model: model is used to relate an impact mass and impact velocity of the fragment to characteristics of its injection and motion Model input: z 4 ¼ (z 14 , z 24 , z 34 ) T , where z 14 is relative mass of the fragment released towards the building (dimensionless quantity); z 24 is horizontal component of the impact velocity (m/s); z 34 is vertical component of the impact velocity (m/s); values of z 14 , z 24 and z 34 are assigned as follows: z 14 ¼ z 12 ; z 24 ¼ m 43 ðz 3 j p 3 Þ; z 34 ¼ m 53 ðz 3 j p 3 Þ Model output: m 4 ¼ ðm 14 ; m 24 Þ T , where m 13 ¼ impact mass of the fragment (kg); m 23 ¼ impact velocity of the fragment (m/s) Model structure: m 14 ðz 4 j p 4 Þ ¼ p 4 z 14 , m 24 ðz 4 jp 4 Þ ¼ ðz 2 24 þ z 2 34 Þ 0:5 , where the parameter p 4 is the total vessel mass which is equal to 1687 kg Quantification of uncertainties: it is assumed that there are no epistemic uncertainties related to m 4 ðz 4 j p 4 Þ Comments on the model: application of m 4 ðz 4 j p 4 Þ implies that the fragment tumbles during its motion and can hit the building at any orientation in the vertical plane of its trajectory; the trajectory is described by the two degrees of freedom (2-D) transport model integrated in the preceding model m 3 ðz 3 ; t j p 3 Þ; in principle, one can apply a 6-D transport model capable to predict the impact orientation of the fragment (Twisdale & Vickery, 1993); this, however, would require to reformulate all models used in the present case study…”

Explosive Damage to Industrial Buildings: Assessment by Resampling Limited Experimental Data on Blast Loading

“…An AE can generate high-speed projectiles (primary and secondary missiles) [1,2,9]. The assessment of eventual explosive damage can be complicated by the necessity to account for impacts of these projectiles (see the damage prediction models and references summarised in p. 494 of [10]).…”

Explosive damage to industrial buildings: Assessment by resampling limited experimental data on blast loading

“…The assessment of eventual explosive damage can be complicated by the necessity to account for impacts of these projectiles (see the damage prediction models and references summarised in p. 494 of [10]). …”