STRUCTURAL RISKS : 1.4 “The human body is capable of surviving .. pressures higher than what conventionally constructed buildings will commonly survive. It is commonly, failed building components or building debris such as walls and columns or being thrown into building interiors, that injures people.” (DOD 2013)   NATURAL DISASTERS FIRE BLASTS K. COLLATERAL DAMAGE L. RIOTS OR CIVIL UNREST WEAPON OF MASS DESTRUCTION STRUCTURAL FAILURE “..objective is to reduce the probability that the building itself becomes a hazard in an explosion Preventing cascading events due to loss of control of process….. an incident in 1 unit should not affect the continued safe operation of other units. Minimising financial losses Building containing… critical equipment ... should be protected.” (Jomy n.d.) STUDY STRUCTURAL ACTION REDUCE THE SEVERITY OF INJURY FACILITATE RESCUE EXPEDITE REPAIR ACCELERATE RETURN TO FULL OPERATION.

EXPLOSIVE REACTION : 1.4.1 BLAST WAVES - SUPERSONIC SPEEDS   BLAST WAVES - SUPERSONIC SPEEDS - REFLECTIONS- MAGNIFY - DIMINUTION WITH DISTANCE

STRUCTURAL ACTION : 1.4.3 AIR SHOCK WAVES INITIAL REFLECTED QUASI BLAST WAVE GROUND SHOCK WAVE SURFACE/RALEIGH WAVE GROUND COMPRESSION RADIAL SHEAR WAVE WAVE PROPERTIES: MULTI DIRECTIONAL DIFFERENT MAGNITUDES DIFFERENT FREQUENCIES = UNPREDICTABLE = LOAD REVERSALS = EXTREME SHEAR PRESSURES OVER A SHORT PERIOD INSTANTANEOUS IMPACT ON: STRUCTURAL SYSTEM & COMPONENTS VARYING AS/PROXIMITY FAÇADE & OTHER INSTALLATIONS FRAGMENTATION, DISMOUNTING, THROWING AROUND

STRUCTURAL REACTION : 1.4.4 “Frame buildings designed to resist gravity, wind loads and earthquake loads in the normal way have frequently been found to be deficient in 2 respects: Failure of beam to column connections Inability to tolerate load reversal.” (Zeynep Koccaz 2008) COLLAPSE LIMIT DESIGN: AVOID OVERALL COLLAPSE THOUGH BUILDING CANNOT FUNCTION ANYMORE FUNCTIONALITY LIMIT DESIGN : CONTINUE FUNCTIONALITY

SEISMIC VS BLAST SIMILARITIES BETWEEN STRUCTURAL DESIGN FOR BLAST AND SEISMIC FORCES 1 DYNAMIC LOADS 2 INELASTIC STRUCTURAL RESPONSE TO BOTH IS THE SOLUTION- IN THE FORM OF DUCTILITY, CONTINUITY AND REDUNDANCY. 3 FOCUS LIES ON LIFE SAFETY IN BOTH CASES 4 NON-STRUCTURAL DAMAGE AND HAZARDS EMANATE FROM BOTH. 5 DANGER OF PROGRESSIVE COLLAPSE* CAN BE ADEQUATELY ADDRESSED IN DESIGN AND EXECUTION. “Addressing blast & seismic design goals may be achieved….An understanding of the differences between these 2 loading phenomenon, effects on the structure and performance requirements are essential to select and implement the appropriate choices..” (WBDG 2014)   “ Progressive collapse is defined as the spread of an initial local failure from element to element, eventually resulting in the collapse of an entire structure or disproportionately large part of it. The initial failure or damage could be from a number of different causes, which might include natural or man-made hazards…” (ASCE 7, WBDG 2014) DIFFERENCES BETWEEN STRUCTURAL DESIGN FOR BLAST AND SEISMIC FORCES   BLAST SEISMIC 1 PROPAGATING PRESSURE WAVE, CREATING EXTREME PRESSURES IN VARYING DIRECTION AND DYNAMIC CHANGES IN DIRECTION LATERAL THRUST DIRECTED AT THE FOUNDATIONS CREATING LATERAL MOVEMENT EVEN IN THE SUPER STRUCTURE. 2 NOT UNIFORM OVER THE BUILDING, INVERSELY PROPORTIONAL TO DISTANCE FROM SOURCE AND BUILDING MASS UNIFORM OVER ALL BUILDINGS, DIRECTLY PROPORTIONAL TO BUILDING MASS 3 LOCAL OR LOCALISED CONTEXTUAL GLOBAL CONCERN INFLUENCED BY GEOLOGY 4 VERY VERY HIGH AMPLITUDES THOUGH NOT VERY WIDE IMPACT MEASUREABLE AMPLITUDES WITH VERY WIDE IMPACT 5 UNPREDICTABLE AND EVER CHANGING PREDICTABLE TO AN EXTENT. 6 SHORT DURATION MAY BE CONTINUOUS OVER A PERIOD OF TIME WITH VARYING DEGREES.

RESILIENT STRUCTURES : 1.4.5 “Blast loads are dynamic loads that need to be carefully calculated, just like earthquake and wind loads” (Zeynep Koccaz 2008)   More attention to design and detailing of structural components Must for exterior bays and lower floors of buildings Shorten slab lengths and improve the punching shear resistance.” Appropriate detailing of slab-column interface. Bottom reinforcement in slabs continuous through column Continuously tied reinforcements in both directions Anchorage of reinforcement at edge of slab Beam to beam connections Beam to column connections. Potential for direct lateral loading on face of columns Adequate ductility and strength. Encasing lower floor columns in steel jackets or steel belts or CFRP Embed steel column within perimeter concrete columns or walls For smaller loads columns and walls with spiral reinforcements. Possibility of uplift Columns designed for transient tensile forces. Progressive collapse analysis Hardening- Several shear walls -beneficial for seismic design also. Central shear wall with a peripheral movement resisting frame.” (Jomy n.d.)

ARCHITECTURAL DEDUCTIONS : 1.4.6 & STRATEGY : 1.4.7 BLAST WAVE= HEMISPHERICAL SHOCK WAVE AMPLIFIED BY REFLECTION MULTI DIRECTIONAL “ DECAY AS FUNCTION OF DISTANCE FROM SOURCE. DIMINISH WITH ANGLE OF OBLIQUITY TO SOURCE” “Designing structures to be fully blast resistant is not a realistic and economical option, however current engineering and architectural knowledge can enhance the new and existing buildings to mitigate the effects of an explosion” (Zeynep Koccaz 2008)   MINIMISE CATASTROPHIC FAILURE EFFECT ON BUILDINGS & ITS OCCUPANTS FLYING DEBRIS MAIN STRUCTURAL CONCERNS FAILED BUILDING COMPONENTS FLYING DEBRIS OCCUPANTS AND PROPERTY BEING THROWN AROUND MEP FAILURE DUE TO DETACHMENT FROM MOUNTING OR STRUCTURAL ATTACHMENT. PROGRESSIVE TOTAL STRUCTURAL COLLAPSE FIRE & SMOKE PANIC AND STAMPEDES COUNTER DESIGN STRATEGY EXPLOSIVE WEIGHT DISTANCE FROM SOURCE STRUCTURAL FORM STRUCTURAL HARDENING ISOLATION OF ASSET MATERIAL SELECTION- FAÇADE & INTERIORS

SECURITY PROGRAMMING I 1.5 “ Probability that the one or more threats will occur is based on historical data extrapolated to the future and considerable probabilistic acumen applied to the time and place of the project in question.”(Demkin n.d.)   STEP 1: THREAT ASSESSMENT STEP 2: BUDGETARY ALLOCATION STRUCTURE I EQUIPMENT I PERSONNEL ONE-TIME VS THE RECURRENT STEP 3: PROGRAMMATIC STATEMENT SECURITY I RESILIENCE AREA REQUIREMENTS, FINANCIALS , STRUCTURALS STEP 4: SECURITY CONCEPT BASED ON ALL OF ABOVE + ARCHITECTURAL CONSIDERATIONS. SHARE WITH THE STRUCTURAL, MEP, LANDSCAPE & INTERIORS TEAMS. STEP 5 DESIGN BRIEF.