Come visit us at this year’s Structures Congress in Denver, Colorado. We have staff presenting on topics using our Extreme Loading® for Structures (ELS) in the following sessions:
Ship Impact & Nonlinear Dynamic Collapse Analysis of a Single Well Observation Platform
Date: Thursday, April 6, 2017
Time: 11:00 AM – 12:30 PM
Track: Non-Building Structures
Abstract: A three-dimensional nonlinear dynamic analysis is performed for a single well observation platform. The structure consists of a single level service deck supported by three driven piles and a bracing frame. Extreme Loading® for Structures (ELS) software was used. The analyses are carried out under the effects of impact for a 3500-ton vessel moving at speeds varying between 1 and 10 knots. The effect of soil type was investigated. The effect accidental failure of a supporting pile was studied and the possibility of progressive collapse of the platform was evaluated. The study found that there is a difference of up to 20% in the results using nonlinear dynamic when compared to the traditional equivalent static analysis. The analysis show that the soil type significantly affects the internal forces in the platform as well as the total platform displacement.
Experimental & Analytical Alternate Load Path Analysis for Reinforced Concrete Flat Plate Systems
Date: Friday, April 7, 2017
Time: 10:00 AM – 11:30 AM
Track: Blast & Disproportionate Collapse
Abstract: Alternative Load Path Analysis (ALPA) is becoming the most common technique for performance based design of structures to resist disproportionate collapse. This has coincided with an increased ability of high fidelity numerical analysis tools validated by experimental work. This paper presents the results of analysis of reinforced concrete flat plate subsystems tested at the University of Missouri and modeled using the Applied Element Method. The experiment analysis shows the importance of modeling membrane action of slabs when performing alternate load path analysis. The results also show that is important to take into consideration brittle failure modes such as the punching shear failure of slabs and the debonding of deformed steel bars.
New Methodology of Designing for ATFP Using Modified Alternate Load Path Method
Date: Saturday, April 8, 2017
Time: 10:00 AM – 11:30 AM
Track: Blast & Disproportionate Collapse
Abstract: A new methodology to design against disproportionate collapse is proposed for critical building that must be operational after a terrorist attack. The disproportionate collapse analysis uses the alternate path method where the structure must be designed to support the applied loads when a column is removed from the building. In some cases, when columns are close to each other, the blast pressure can damage more than one column. The new methodology can identify the number of columns or vertical load bearing components that should be removed in a disproportionate collapse analysis. Then, an alternate load path analysis is to be performed using the applied element method for the cases where one or more vertical load bearing components fail to match the actual risk level for critical structures and provide consistent design benchmarks. The applied element method is an optimized numerical technique which allows the analysis to be completed within a time-frame that is practical for design professionals. The method also allows the designer to choose the required resilience or the acceptable degree of risk based on the actual performance of the structure and the amount of acceptable damage under the effects of extreme loading events.
