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This paper presents a realistic model for the simulation of a progressive collapse scenario in a typical low-rise building that is constructed from RC flat slabs and supported by columns. The progressive collapse scenario starts after failure of the top slab connections, where the slab is falling downward and impacts with the slab below. This impact event is analyzed, and the dynamic failure of the impacted slab’s connections starts the progressive collapse event. Two different scenarios are identified, depending on the first slab damage condition prior to impact. The first scenario refers to an undamaged impacting slab where an elastic collision occurs with the slab below; in the second scenario, the first slab is damaged, and its collision with the slab below is plastic. In the first scenario, the impacting slab velocity drops to zero while its velocity is fully imparted to the impacted slab. In the second scenario, both slabs continue their motion jointly at a common velocity. In the subsequent impacts, the impacting slabs are a-priori damaged, hence plastic collisions occur. These impact occurrences are analyzed separately, depending on the number of impacting slabs involved, damage characteristics, and impact velocity. Due to the nature of the first impact, the first scenario is characterized by separate motion of the first impacting slab which is falling behind the other slabs. This slab gains speed until it meets the other falling slabs below at a certain altitude, and an intermediate collision occurs, not necessarily at a floor level. In the analyzed five-story building, the intermediate impact occurs after the third impact event, where the slabs are located slightly above the first story level. The intermediate impact elevates the velocity of the impacted slabs such that their impact with the first level slab is more severe and its motion toward hitting the ground level is faster.

This article presents numerical simulations of tsunami waves that are generated using different experimental techniques in laboratory tests. Comparisons of the numerical predictions of the tsunami wave shapes with different experimental measurements of the wave shapes have been carried out, and a good agreement was obtained. Four different laboratory techniques to create tsunami waves were examined: a sudden release of a water column, a horizontal or vertical motion of a piston, and a rotation of a rigid plate. Comparison of waves of the same height that are formed by these four different methods shows that the horizontal piston motion produces the shortest wave, and the vertical piston motion produces the longest wave. The wave produced by a plate rotation is similar to the wave caused by the "water column release," but it is slightly longer. It was found that different techniques produce different wave characteristics; therefore, selection of the proper laboratory technique requires some considerations including a comparison with the required real tsunami wave that should be simulated. It should be emphasized that this research aims at simulating the tsunami waves that are produced by different common laboratory techniques; however, it refrains from assessing the adequacy of any of this techniques to properly represent a real specific tsunami wave. Further to developing the computational procedures for tsunami wave simulations, this article extends the numerical study to examine the interaction of a tsunami wave with a rigid wall and investigate the dynamic pressure distribution on the wall surface. It was found that the peak pressure of a tsunami wave acting on a rigid wall that is produced by the horizontal piston has the lowest magnitude (among the waves of the same height, caused by these four techniques), while the pressure due to a rotational plate has the highest magnitude.