Integrated Civil Engineering Design Project (Building Structure Design Example) CIVL 395 HKUST By : Ir. K.S. Kwan Date: 4/07

Architectural Consideration Limitation (plot ratio, height, public facilities, slope) View/light/Wind climate Flat size, Number of Blocks Podium (Other Facilities – Cube house/ Carpark/ Commercial complex) Budget estimation Other considerations

Structural Engineer Consideration Any site construction difficulties Site Access Construction platform Foundation option Time for completion Tower Design To provide a cost-effective solution

Lack of flexibility by structural element Case A : 45 storey Lack of flexibility by structural element End wall should be effectively used as shear wall to provide better stiffness

To enhance the stiffness of building by linking the walls as much as possible

Lack of flexibility by structural element Too much wall No support for slab

Wall not allowed in front of stairs Beam ahead bedroom Too much wall End wall should be effectively used as shear wall to provide better stiffness

Structural Framing Plan Secondary Beam for gravity load only Aspect ratio = 45x3/19 =7.0 Lintel Beam For both wind load and gravity load

Case B: 15 storey

Aspect ratio = 15x3/60 =0.75 Column structure used

Case C: 57 storey

Aspect ratio = 57x3/24.3 =7.03

Podium Structure To confirm the column layout under transfer structure To confirm the transfer plate/column layout To confirm the size of transfer structure (e.g. thickness of transfer plate) Evaluate the tower loading and estimate the size of transfer structure size

Tower Framing plan

Transfer Structure under tower

Supporting columns under transfer structure

Other beam/column structure below

Other beam/column structure below

Other beam/column structure below

Preliminary Computer Model Use the effective members for first model Estimate the member size for model input based on gravity load first and provide some reserve for wind load (say 20 ~40% of wind load) Check top deflection < H/500

Minor wall not selected for preliminary modeling Only analysis the critical wind direction Only use the effective members for modeling Minor wall not selected for preliminary modeling Width of building to calculate the wind load

For preliminary model, only typical floor is used to simulate the whole tower. Building height should be maintained Tower model Podium model

Element Checking Check critical lintel beam force (e.g. check wind shear stress v=V/bd ) Check critical element force (e.g. wall element under high compression/tension)

Loading Schedule Checking Check average gravity load (Total D+L/Gross Floor Area = 15~20 KN/m2 Total axial force = 0 Check total wind shear force = total wind force applied at the building

Q & A