1	Non Linear Blast Analysis
2	Initiators Blast Assessment Initiators: 1. Risk Level* A. Probability of Occurrence B. Exposure Category 2. Design Criteria
3	Blast Wave Shock Wave 1. Sudden pressure rise Pressure Wave 2. Gradual pressure rise
4	Pressure Idealization Idealize shock load and pressure load into equivalent pressure load P_r = Peak reflected overpressure t_c = Clearing time P_s = Stagnation pressure
5	Modeling General 1. Use strength and dynamic increase factors on yield stress (instead of nominal)* 2. Declare secondary elements as “Elastic”. Avoid: 1. Stiffened, corrugated & membrane plates (isotropic OK) 2. Special cross section types (ie. dented, stiffened, etc.) 3. Shell or solid elements 4. User defined stiffness properties
6	Modeling (cont’d) Blast Unit Loading 1. Include unit pressure load on walls, components, etc. 2. Make separate unit load case for each component
7	Analysis Parameters General Options Strain Hardening Joint Flexibility Joint Strength Local Buckling Overrides Secondary members as elastic Joint strength parameters (RSFAC, RSFACO lines)
8	Analysis Parameters (cont’d) Complex Connections 1. Include stiffness overrides (may require FE study)
9	Analysis Parameters (cont’d) Dynamic Damping Time duration and increment Load Time History Define blast profile time history (LOADC lines)
10	Load Sequence Dead Load and Weights Apply dead load and weights first Apply appropriate live loads Use combinations if possible (requires “CMB” option) Blast Loading Automatically included by Dynamic Response
11	Results Collapse shows plasticity over time with each load step representing a time increment
12	Non Linear Blast Analysis