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In this paper, predictions of along-wind base moments for a generic tall building from several wind tunnels from an international benchmark study, are compared with those from three codes and standards: the Hong Kong Code of Practice (2004), the Australian/New Zealand Standard, and the American Standard (ASCE 7). There are significant differences in the predictions from the codes, with two of the codes producing lower values than the average of the wind tunnel data. In the case of the Hong Kong Code, the specified drag coefficients for the building are significantly lower than the effective drag coefficients derived from the other standards, and from the measurements. The lower predictions from ASCE 7 can be partly attributed to an apparent inconsistent formulation in the numerator of the expression for the gust effect factor for dynamic structures. Predictions of cross-wind base moments and resultant accelerations from the Australian/New Zealand Standard, have also been compared with the wind-tunnel data. The comparisons are good, with the Standard giving predictions close to the averages of the wind-tunnel data for the cross-wind moments, and close to the upper limits of the wind-tunnel data for the resultant accelerations. [ABSTRACT FROM AUTHOR]

simplified method has been developed to predict smoke behavior subject to a sprinkler spray. The method considers whether downdrag is likely to occur and the distance that smoke is then pulled down should downdrag be present. The method is validated using third party experimental data. Empirical equations are applied in the calculations to determine the heat loss from a smoke layer due to the sprinkler spray and therefore the smoke layer temperature. Comparative results show that the simplified method might expect the onset of smoke downdrag regardless the difference in temperature predictions. The empirical equation to predict the penetration depth of downdrag smoke is based on previous research and compared with third party experimental data. The predicted depths are acceptable for engineering use. For a 15 mm nominal sprinkler the water flow rate that leads to the onset of downdrag for typical smoke layers up to 2 m in depth is less than 100 L/min which leads to an operating pressure being less than 0.16 MPa. Experimentally data for sprinklers other than the 15 mm nominal sprinklers are unavailable and therefore the method should be used with care for any other sprinkler. [ABSTRACT FROM AUTHOR]

• Strike-slip shear zones are often comprised of evenly-spaced faults. • An analytical model is established to reveal controls on fault spacing in crust. • Increasing brittle layer or lower crust thickness may increase fault spacing. • Inverse relation between fault strength or lower crust viscosity and fault spacing. • Lower crust viscosity in California, New Zealand and central Tibet is estimated. Strike-slip shear zones with sub-parallel arrays of evenly-spaced faults are widely observed in nature, but the controls on the spacing between major faults are unclear. We analyze a 2-D model and develop a scaling law relating the fault spacing to structural and rheological parameters in the continental crust. We find that fault spacing positively correlates with brittle-layer thickness, viscous lower crust thickness, and strength contrast between active faults and surrounding intact blocks; and is inversely correlative with lower crust viscosity. This is corroborated for either a zero-shear traction (decoupled) or a prescribed velocity (coupled) basal boundary condition in the 2-D analytical solution. The zero-shear traction boundary condition represents low viscosities in the lowermost crust or the topmost mantle that may decouple deformations from mantle flow. The prescribed velocity boundary condition emphasizes basal drag tractional forces imparted on the lower crust by a strong mantle. For a viscous layer that is thicker than half of its average fault spacing, models with either of the boundary conditions produce the same results. Otherwise, a thinner, viscous layer with a linear-velocity condition tends to produce smaller fault spacings than a no-shear model, all else being equal. These theoretical models are comparted to data from shear zones in California, the Marlborough Fault Zone in New Zealand and central Tibet. Modeling indicates that the effective viscosity of the viscous layer underlying the brittle layer in all of the selected areas is 2 × 10 20 to 4 × 10 21 Pa⋅s. The subducted oceanic plate attached to the lower crust of the eastern Marlborough Fault Zone also appears to influence fault spacing in the overriding plate. [ABSTRACT FROM AUTHOR]