2008/08/21 by Charles M. Beck, Beck, Charles M.
Engineering · Physics and Astronomy · #FOS: Physical sciences #Geotechnical and Geomechanical Engineering #Hydraulic Fracturing and Reservoir Analysis #Popular Physics (physics.pop-ph) #Rock Mechanics and Modeling #physics.pop-ph
paper · pdf · doi:10.48550/arxiv.0808.2846
6 pages, 1 figure, submitted to J. Engr. Mech ASCE
arxiv created 2008/08/21 · openalex publication_date 2008/08/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We derive a mathematical model of progressive collapse and examine role of compaction. Contrary to a previous result by Bažant and Verdure, J. Engr. Mech. ASCE 133 (2006) 308, we find that compaction slows down the avalanche by effectively increasing the resistive force. We compare currently available estimates of the resistive force, that of Bažant and Verdure (2006) corrected for compaction for World Trade Center (WTC) 2, and of Beck, www.arxiv.org:physics/0609105, for WTC 1 and 2. We concentrate on a damage wave propagating through the building before the avalanche that figures in both models: an implicit heat wave that reduces the resistive force of the building by 60% in Bažant and Verdure (2006), or a wave of massive destruction that reduces the resistive force by 75% in Beck (2006). We show that the avalanche cannot supply the energy to the heat wave as this increases the resistive force by two orders of magnitude. We thus reaffirm the conclusion of Beck (2006) that the avalanche is initiated in the wake of the damage wave.