ETABS & SAFE Course Eng. Ahmad Traboulsi Eng. Ahmad Traboulsi ETABS & Safe course 1 Outline 1. Introduction to the Structural Design 2. Description of the Project worked on 3. Determination of the dimensions of the structural elements 4. Introduction to ETABS 2016 5. ETABS model 6. Earthquake loads Columns and Shear Walls 7. Introduction to SAFE 2016 8. Design of Footings 9. Design of Slabs and Beams 10. Deflection Short and Long term Eng. Ahmad Traboulsi ETABS & Safe course 2 Introduction • ETABS 2016: 1. 2. 3. 4. Columns Shear Walls Earthquake design Wind design • SAFE 2016: 1. 2. 3. 4. Slabs Beams Foundations Deflection Eng. Ahmad Traboulsi ETABS & Safe course 3 Description of the Project Residential Building 15 stories + One basement located in Lebanon F’c = 25Mpa for horizontal element (Slabs and Beams) F’c = 30 Mpa for Vertical element (Columns, Walls, and Foundations) Fy = 420Mpa (longitudinal reinforcement) Fyt = 240Mpa ( transversal reinforcement) Qa = 3kg/cm2 (Bearing capacity of soil) Height of the basement 4m Height of the typical stories 3m We use Shear Wall system for earthquake design R=5.5 Eng. Ahmad Traboulsi ETABS & Safe course 4 Description of the Project Assume thickness of shear walls 40cm All columns are with minimum dimensions 600x250mm We will use the ACI code for the structural design Eng. Ahmad Traboulsi ETABS & Safe course 5 Waffle Slab Story 1 and 2 Ribbed Slab Story 3 Flat Slab Story 4 Solid Slab from story 5 to 16 Story 1 Waffle Slab Type 1 Eng. Ahmad Traboulsi ETABS & Safe course 10 Story 1 Waffle Slab Type 1 • Two Way • We use waffle slab when we have long spans and high live load • Spacing between ribs above 1m and below 2m • Loads: 1. Dead Load = 3.5 kN/m2 (Type of Slab) 2. Live Load = 5 kN/m2 (Parking) Spacing > 1 m Interior without Drop Interior with Drop Exterior without Drop Exterior with Drop L/22 L/24 L/20 L/22 Where L = L average = (Lx + Ly / 2) Eng. Ahmad Traboulsi ETABS & Safe course 11 h slab= 710+548 𝑥0.5 20 =31.45cm = 32cm We need to use hidden beams so h slab = h beams h beams ? Simply One end Two end Cant Drop L/14 L/15 L/16 L/6 Hidden L/16 L/18.5 L/21 L/8 h beam = 695 = 38 cm 18.5 So h slab = h beam = 38 cm S1=S2=1.6m; Tf= 8cm; Rw=20cm The section of the beam in story 1 is B 100x38 Eng. Ahmad Traboulsi ETABS & Safe course 12 Story 2 Waffle Slab Type 2 • Two Way • We use waffle slab when we have long spans and high live load • Spacing between ribs below 1m • Loads: 1. Dead Load = 3.5 kN/m2 (Type of Slab) 2. Live Load = 5 kN/m2 (Parking) Spacing < 1 m Interior without Drop Interior with Drop Exterior without Drop Exterior with Drop L/27 L/30 L/24 L/27 Where L = L average = (Lx + Ly / 2) Eng. Ahmad Traboulsi ETABS & Safe course 13 h slab= 710+548 𝑥0.5 24 = 26.25 = 27cm We need to use hidden beams so h slab = h beams h beams ? Simply One end Two end Cant Drop L/14 L/15 L/16 L/6 Hidden L/16 L/18.5 L/21 L/8 h beam = 695 = 38 cm 18.5 So h slab = h beam = 38 cm S1=S2=0.8m; Tf= 8cm; Rw=20cm The section of the interior beam in story 2 is B 100x38 The section of the exterior beam in story 2 is B 25x75 = 2 x h slab Eng. Ahmad Traboulsi ETABS & Safe course 14 Story 3 One Way Ribbed Slab Eng. Ahmad Traboulsi ETABS & Safe course 15 Story 3 Ribbed Slab • One way parallel to y axis • We use ribbed slab for residential • Loads: 1. Dead Load = 4.5 kN/m2 (Type of Slab) 2. Live Load = 2 kN/m2 (residential) Simply One end Two end Cant Drop L/20 L/24 L/28 L/10 Hidden L/16 L/18.5 L/21 L/8 Where L = L parallel to the ribs so h slab = 695/18.5 = 38cm h beam = 38cm B 100x38 Eng. Ahmad Traboulsi ETABS & Safe course 16 Story 4 Flat Slab Eng. Ahmad Traboulsi ETABS & Safe course 17 Story 4 Flat Slab • Flat slab easy in construction • Loads: 1. Dead Load = 3 kN/m2 (Type of Slab) 2. Live Load = 2 kN/m2 (residential) h flat slab = L / 33 = 710+548 𝑥0.5 33 = 19cm = 20cm Where L = L average h beam = 3 x h slab = 3 x 20 = 60cm so B25x60 Eng. Ahmad Traboulsi ETABS & Safe course 18 Story 5 Solid Slab Eng. Ahmad Traboulsi ETABS & Safe course 19 Story 5 Solid Slab • Solid slab efficient in seimic • Loads: 1. Dead Load = 3 kN/m2 (Type of Slab) 2. Live Load = 2 kN/m2 (residential) h solid slab= Perimeter / 140 = 570x1+570x0.76+695x1+695x0.76 140 = 16cm We multiply the non continuous side of the panel by 0.76 h beam = 3 x h slab = 3 x 16 = 48cm so B25x50 Eng. Ahmad Traboulsi ETABS & Safe course 20 Stair • H stair = 18 cm we draw the stair in ETABS as solid slab • Dead Load on the stair = 3 KN/m2 • Live load on the stair = 4 KN/m2 Eng. Ahmad Traboulsi ETABS & Safe course 21 Loads on Beams • Wall 20cm : Loads= 12KN/m • Wall 15cm : Loads= 9KN/m • Wall 10cm : Loads= 6KN/m Eng. Ahmad Traboulsi ETABS & Safe course 22 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 23 Earthquake Design • Regular < 73m Static • Regular > 73m Dynamic • Irregular < 21m Static • Irregular > 21m Dynamic • Irregular number of stories 5 and above Dynamic • Eccentricity between center of mass and rigidity > 20% Dynamic Eng. Ahmad Traboulsi ETABS & Safe course 24 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 25 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 26 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 27 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 28 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 29 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 30 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 31 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 32 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 33 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 34 Earthquake Design Eng. Ahmad Traboulsi ETABS & Safe course 35 Wind Velocity • Wind speed in Lebanon Vk= 33m/s • ETABS needs velocity V in mi/h • V=Vk When L1 and L2 below 10m • V=Vk/1.35 if L1 or L2 between 10m and 20m • V=Vk/1.45 if L1 and L2 above 20m • To convert from m/s to mi/h we multiply by 2.236 so V=51mi/h Eng. Ahmad Traboulsi ETABS & Safe course 36 Stiffness Modifier • • • • Slab 0.25 Beams 0.35 Wall 0.5 Column 0.7 Eng. Ahmad Traboulsi ETABS & Safe course 37 Story displacement • Limit of story displacement = L / 500 Where L is the height of the structure on mm Eng. Ahmad Traboulsi ETABS & Safe course 38 Story Drift Eng. Ahmad Traboulsi ETABS & Safe course 39 Story Drift Eng. Ahmad Traboulsi ETABS & Safe course 40 Deflection Eng. Ahmad Traboulsi ETABS & Safe course 41 Deflection Eng. Ahmad Traboulsi ETABS & Safe course 42 Deflection Eng. Ahmad Traboulsi ETABS & Safe course 43
