www.ozsaferooms.com Senior Design 2003- -2004 2004 Senior Design 2003 Project # 04024 Project # 04024 Team: Team: Chris Moore (ME) Chris Moore (ME) Brett Kimball (ME) Brett Kimball (ME) Matt Barton (ME) Matt Barton (ME) Matt Weaver (ME) Matt Weaver (ME) Brian Conway (ISE) Brian Conway (ISE) Rugwed Phatak (EE) Rugwed Phatak (EE) Faculty Mentor: Benjamin Varela (ME) Faculty Mentor: Benjamin Varela (ME)
Zagorski Forms Specialists, Inc Forms Specialists, Inc Zagorski � Drew Drew Zagorski Zagorski, Sr. is the , Sr. is the � inventor of OZ Saferooms Saferooms inventor of OZ � Continuously Poured, Steel Continuously Poured, Steel- - � Reinforced, Concrete Reinforced, Concrete Structures Structures � Tornado safe room Tornado safe room � � Fabricated on Fabricated on- -site site � � Headquartered in Rochester, Headquartered in Rochester, � NY NY � Installed 53 safe rooms since Installed 53 safe rooms since � Survived the passage of an F5 tornado on May 8, 2003 2000 (New York, Texas, 2000 (New York, Texas, Moore, Oklahoma Oklahoma) Oklahoma) R-I -T OZ Saferooms Project # 04024
Project Description Project Description Project Objective: Analyze the structure to determine its survivability Project Objective: Analyze the structure to determine its survi vability � � � Finite Element Analysis (FEA) Finite Element Analysis (FEA) � � Experimental impact testing Experimental impact testing � � Sensor package design Sensor package design � Scope Limitations Scope Limitations � � � Budget = $2000 Budget = $2000 � � Time period = 20 weeks Time period = 20 weeks � � Did not analyze the structure Did not analyze the structure’ ’s door s door � Stakeholders Stakeholders � � � Zagorski Zagorski Forms, Families, Federal Emergency Management Agency (FEMA), Forms, Families, Federal Emergency Management Agency (FEMA), � RIT, local authorities and rescue workers RIT, local authorities and rescue workers Key Business Goals of Zagorski Zagorski Forms Forms Key Business Goals of � � � Testing will quantify stresses on structure Testing will quantify stresses on structure � � FEMA support FEMA support � � Consumers to buy product Consumers to buy product � R-I -T OZ Saferooms Project # 04024
Deliverables Deliverables � Mechanical Properties Mechanical Properties � � Determine mechanical properties of concrete by 3 Determine mechanical properties of concrete by 3- -point bending and point bending and � compression testing compression testing � Impact Test Impact Test � � Impact test on existing OZ Impact test on existing OZ Saferoom Saferoom � � Provide data and calculations from impact test Provide data and calculations from impact test � � Finite Element Analysis (FEA) Finite Element Analysis (FEA) � � FEA on three structures FEA on three structures � � FEA on FEA on Zagorski Zagorski Forms Forms’ ’ preliminary design of a 20 ft. x 30 ft. structure preliminary design of a 20 ft. x 30 ft. structure � � Compare FEA and impact test results Compare FEA and impact test results � � Determine the conditions under which the structure will fail Determine the conditions under which the structure will fail � R-I -T OZ Saferooms Project # 04024
Mechanical Testing of Concrete Samples Mechanical Testing of Concrete Samples Experimental Procedure and Data Analysis Experimental Procedure and Data Analysis ASTM C 78- -02 three 02 three- -point bending point bending ASTM C 78 ASTM C 39 compression test ASTM C 39 compression test � � � � test test Determine compression strength of Determine compression strength of � � Determine flexural strength or Determine flexural strength or � � cylindrical concrete specimens cylindrical concrete specimens modulus of rupture modulus of rupture ' = 4 F = 57 000 , ' E f f σ bend = 3 π FL c c c 2 d 2 2 wh 9 samples (6 in diam 9 samples (6 in diam., 12 in. length) ., 12 in. length) � � 9 samples (14 in. x 4 in. x 4 in.) 9 samples (14 in. x 4 in. x 4 in.) � � Load max σ bend Load max f’ c W (lb) (lb) (psi) W (lb) (lb) (psi) AVG AVG 19.075 2528 711 27.65 227157 8034 STDDEV STDDEV 0.121 501 141 0.137 8868 314 Conclusion Conclusion � � 6 psi E = 5.11 x 10 6 psi E = 5.11 x 10 � � ρ = 141 lb/ft = 141 lb/ft 3 3 ρ � � R-I -T OZ Saferooms Project # 04024
= 6 f f ' r c Finite Element Analysis Finite Element Analysis I- -DEAS DEAS I � � � The software assists in calculating The software assists in calculating � stress, shear force, loads, stress, shear force, loads, deflections, frequency response deflections, frequency response and other parameters and other parameters Four different structures (outside Four different structures (outside � � dimensions) dimensions) � Existing 78 in. x 78 in. x 92 in. safe Existing 78 in. x 78 in. x 92 in. safe � room room � 102 in. x 102 in. x 92 in. safe room 102 in. x 102 in. x 92 in. safe room � � 126 in. x 126 in. x 92 in. safe room 126 in. x 126 in. x 92 in. safe room � � Preliminary design of 20 ft. x 30 ft. Preliminary design of 20 ft. x 30 ft. � x 92 in. safe room x 92 in. safe room Assumptions Assumptions � � � Properties of Concrete determined Properties of Concrete determined � from experimental testing from experimental testing Preliminary analysis on four structures � Monolithic Pour Monolithic Pour 2500 lb. distributed load � � Rebar not analyzed Rebar not analyzed � R-I -T OZ Saferooms Project # 04024
Finite Element Analysis Finite Element Analysis Verify Mesh: H- -Convergence Convergence Verify Mesh: H Mesh size (in^2) Displacement (in) Stress (psi) % Difference displacement % Difference Stress 4 2.02E-04 8.43 - - 5 1.99E-04 8.35 1.49 0.95 7 1.95E-04 6.37 3.47 24.44 10 1.91E-04 6.26 5.45 25.74 Note: 78 in. x 78 in. x 92 in. Structure Mesh Values 2500 lb Distributed Load Mesh = 4 Mesh = 7 Mesh = 10 R-I -T OZ Saferooms Project # 04024
Finite Element Analysis Finite Element Analysis Failure Analysis Failure Analysis � � � Concrete is strong in Concrete is strong in � compression and weak in tension compression and weak in tension � Cracks develop whenever loads Cracks develop whenever loads � induce tensile stresses in excess induce tensile stresses in excess of the tensile strength of the tensile strength � Failure if Max Stress > Failure if Max Stress > f f r � r = = 6 ' 538 f f psi r c Applied Pressure - Applied Pressure - Von Mises Applied Pressure - Applied Pressure - Von Mises Structure Roof Roof Stress Wall Wall Stress (psi) (lbs.) (psi) (psi) (lbs.) (psi) 78 in. x 78 in. 231192 39468 38 539 5.5 574 x 92 in. 102 in. x 102 223686 56304 21.5 545 6 610 in. x 92 in. 126 in. x 126 246078 81144 15.5 544 7 542 in. x 92 in. 240 in. x 360 241920 629280 2.8 540 19 538 in. x 92 in. R-I -T OZ Saferooms Project # 04024
Impact Test Impact Test Acceleration vs. Time 30 Impact Testing (April 16, 2004) Impact Testing (April 16, 2004) � � 20 acceleration (ft/s^2) 10 � Existing safe room in Macedon, NY Existing safe room in Macedon, NY � 0 3.98 4 4.02 4.04 4.06 4.08 4.1 4.12 4.14 4.16 -10 � 485 lb. pallet full of sand bags dropped 485 lb. pallet full of sand bags dropped � -20 from 20 ft. from 20 ft. -30 t (sec) � Acquire structure Acquire structure’ ’s deflection and s deflection and � Deflection vs. Time frequency response data frequency response data 0.0025 � This data was then compared with This data was then compared with � 0.002 deflection (in) finite element analysis to verify the finite element analysis to verify the 0.0015 models and results were correct 0.001 models and results were correct 0.0005 0 4 4.1 4.2 4.3 4.4 4.5 4.6 t (sec) Frequency Response 600 400 |H(f)| 200 0 0 200 400 600 -200 freq (Hz) R-I -T OZ Saferooms Project # 04024
FEA and Impact Test Comparison FEA and Impact Test Comparison � Frequency Response Frequency Response Failure Analysis of roof slab Failure Analysis of roof slab � � � Johanson’ ’s s Yield Line Analysis Yield Line Analysis � Impact Test Impact Test Johanson � � � Theory addresses the Yield Line st resonant frequency = 15 Hz Theory addresses the Yield Line � � � 1 1 st resonant frequency = 15 Hz � Criterion used for the elasto elasto- -plastic plastic Criterion used for the nd resonant frequency = 260 Hz � 2 2 nd resonant frequency = 260 Hz � behavior of a reinforced concrete slab behavior of a reinforced concrete slab � Modal Analysis of structure Modal Analysis of structure’ ’s roof s roof Max theoretical distributed load = 14.5 Max theoretical distributed load = 14.5 � � � (88,218 lbs.) st natural frequency = 315 Hz (88,218 lbs.) � 1 1 st natural frequency = 315 Hz � FEA of roof slab FEA of roof slab � � � No rebar applied No rebar applied � 88,218 lb. distributed load applied 88,218 lb. distributed load applied � � Resulting stress = 615 psi psi Resulting stress = 615 � � 15% higher than theoretical tensile 15% higher than theoretical tensile � � strength (538 psi psi) ) strength (538 R-I -T OZ Saferooms Project # 04024
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