Step 1 - Generative Design Framework
Construction Planning:
Objective: Minimize the Construction cost and maximize the space efficiency of a tower
Model: In a grid of buildings, set the height of the building, top radius, and middle radius are considered to be the inputs, tower’s base form is the constant.
Design Variables: Building height (given range, 500-700 ft), top radius and rotation, middle radius, and rotation.
Constants: tower location, tower’s base form
Evaluators: Construction Cost, Space Efficiency
Interpretation: With a given base form, find the best tower form that has the lowest construction cost and highest space efficiency, while the larger floor area will cause a higher construction cost but could lead to higher space efficiency.
Architectural Design
Objective: Minimize the glass panels cost and maximize the directness of sun
Model: In the given building form of the building, set the locations and areas of the glass panels as input to maximize the directness of sun and minimize the glass panels cost.
Design Variables: Locations (x, y, z) and areas of the glass panels
Constants: Building Form
Evaluators: Materials Cost, directness of sun
Interpretation: With a given building form, find the maximum directness of sun and minimize the windows materials cost. The tradeoff is between the panels cost and directness of sun, since larger panels will have a better directness of sun and also lead to a larger cost.
Sustainability
Objective: Minimize the materials cost and maximize the solar insolation potential
Model: Set the tower’s top, and middle radius and rotations as input, maximize the solar insolation potential and minimize the materials cost
Design Variables: Tower’s top radius and rotation, middle radius, and rotation, tower height.
Constants: Tower’s base geometry, tower location
Evaluators: Capital Cost, Roof Insolation Potential
Interpretation: With a given base form, find the best tower form that has the minimum materials cost and maximum solar insolation potential. The solar insolation potential is related to top radius and rotation, but a larger roof area will have a higher material cost.
Step 2 - Generative Design Study
My generative design study combines construction, architectural, and sustainability aspects.
Inputs: In this study, three twisting towers are created and placed close to each other. The location of the first tower is fixed and the origin is (0,0), and the locations of the other two towers are set as input. Also, all the base radius, middle radius and rotations, top radius and rotations, and tower height are set to be the input as shown in Figures 2 and 3.
Evaluators: The evaluators in this study are Capital Cost (Material Cost + Construction Cost), Roof Solar Insolation Potential, Views From a North point, and Tower to Tower Distance. The goal is to maximize the views, roof solar insolation potential, and minimize the capital cost and tower distance.
Constants: In this study, the location of the first tower is fixed, and there is a constant value of material cost ($50) per sqft, and construction cost is linearly increasing from bottom to top.
The tower model is created by lofting the base curve, middle curve, and top curve, then each surface is filtered by using the code block shown in Figure 4.
Capital Cost:
Controlling the cost is significant and capital cost is selected as one of the evaluators. Figure 5 shows the inputs for calculating the capital cost, and Figure 6 shows the calculation for the Capital Cost. Capital cost is defined as construction cost plus material cost. The wall surfaces and roof surface are pulled out and the total area is calculated for calculating the material cost. It is assumed that the construction cost is linearly increasing from bottom to top, and material cost is set to be $50/sqft.
Roof Solar Insolation Potential:
Roof PV panels could be set up to transfer the solar energy to electricity so the roof solar insolation potential is selected as one of the evaluators. The inputs for solar analysis are shown in Figure 7, and the calculation is shown in Figure 8. It is assumed that the tower is self-shading and also will be shaded by the surrounding tower.
Views from a North Point:
For the three towers study, views are important to make sure each tower has the best visibility from the inside and outside. The setup for views analysis is shown in Figure 9. Only the North point is analyzed because the west and east views are assumed unobstructed, only north or south views will be affected. The boundary faces of the front and middle tower are found and combined as a list, then the analyzed faces of the back tower are found and set as the input to calculate the rays that hit the faces. Figure 10 shows the calculation of unobstructed views to the analyzed faces.
Tower to Tower Distance:
For the three towers study, the tower to tower distance is calculated as shown in Figure 11. Each location of the tower is set as the input to calculate the distance, then all distances are added together as the output. I want to keep towers close to each other so the open space could be reduced and towers won’t be isolated.
Tradeoff:
There are multiple tradeoffs between the four evaluators. As to maximize the views, the distance between each tower would be larger, and the back tower could be taller, but with one taller tower, the solar insolation potential could be decreased by the larger shading area. Also, with a larger roof area, the solar potential would be higher but the capital cost would also increase.
Step 3 - Generative Design Study Results
The study is set up as shown in Figure 13, I want to minimize the capital cost and tower distance, and maximize the roof solar insolation potential and views from a north point.
The outcomes are shown in Figure 14, when the capital cost is larger, we tend to have a higher roof solar insolation since the roof area is larger. Lower capital cost design usually comes with smaller views and less solar potential, this could be caused by less surface area and shorter towers. Smaller tower distances tend to have a lower roof solar potential because of the shading from each other towers. In general, the higher capital costs could benefit all other three evaluators, I would consider a higher cost option if it is possible.