Finite element analysis of interaction of tornados with a low-rise timber building

Some Considerations for the Use of High-Resolution Mobile Radar Data in Tornado Intensity Determination

“…Since there are wind speeds associated with the EF scale, damage assessors use the relevant damage indicators (DIs) and degree of damage (DoD) levels to arrive at an EF-scale category and, typically, an estimate of maximum wind speed. These ratings have been used for the study of tornado climatology across the United States and the correlation of environmental parameters with the occurrence of tornadoes of particular intensity (e.g., Kerr and Darkow 1996;Brooks and Doswell 2001;Brooks et al 2003; Thompson et al 2003Thompson et al , 2007Brooks 2004;Mead and Thompson 2011;Garner 2012); the EF scale ratings are of interest to meteorologists as well as to those in many other industries (e.g., Womble and Smith 2009;Womble et al 2009Womble et al , 2011Thampi et al 2011;Kuligowski et al 2013). For a general discussion on the history, development, advantages, and limitations of the EF scale, readers are referred to Doswell et al (2009) and Edwards et al (2013).…”

Finite Element Modeling of the Progressive Failure of a Low-Rise Building under Uniform Uplift Pressure

“…The actual discontinuities between sheathing panels are negligible for conventional design that assumes no part quits from the service load level and this simplification is justified by the denser nails at the conjunction line than anywhere else or the presence of H-clips. However, the accurate modeling of each sheathing panel by its actual dimensions instead of one meshed area per roof or wall is essential for the damage prediction and the same concern was noticed by Thampi et al (2011) in the simulation of the damage of residential buildings to tornados. The panel to panel simulation was chosen to reflect the realistic effects in the field without overestimating the diaphragm stiffness.…”

“…The ridge board and the top chords of the gable-end trusses were made of 38 mm × 184 mm (known as "2×8") studs. The connections followed the four categories summarized by Thampi et al (2011) as (1) wall studs to the sole and the head plate by 2-16 d face nails (88.9 mm L× 4.11 mm D); (2) trusses to the head plates by3-8d common toe nails; (3) sheathing panels to beam/ stud, and (4) special type roof uplift connectors to the head plate. Moreover, the trusses were connected at the corners to the head plate by a minimum of 4-8d common toe nails per corner in addition to special roof uplift connections.…”

“…Database Assisted Design (DAD) has been accepted as one alternative for designers by ASCE 7-98 (Rigato et al 2001). Because this approach is inherently adaptive to wind tunnel tests or field tests, it has been used in conjunction with Finite Element (FE) model for the load path study (Martin et al 2011), the stress analysis in timber structure (Kumar 2008), the equivalent static wind loads study (Chen and Zhou 2007), and damage prediction by tornado (Thampi et al 2011). However, the application of Database Assisted approach in the damage prediction under hurricane is very rare, especially to trace the progressive failure procedure resulting from the wind-structure interaction.…”

“…A number of models related to wind have been developed based on the extensive efforts of modeling the substructure, i.e., roof truss or joints, and on modeling the building system under seismic load. Roof and wall sheathing were modeled by 3D shell elements with 4 to 8 nodes and 6 degrees of freedom (DOF) at each node to reflect the in-plane and out-of-plane behavior (Kumar 2008;Asiz et al 2010b;Thampi et al 2011;Martin et al 2011). The frame, including the truss and studs were modeled by 3D beam elements and the connectivity between sheathing and frame or from frame to frame were pinned or rigid.…”