Cynthia Zhan

• Structural Design - Column/Beam Framing Spacing
• Design Variables
• Column Spacing (could potentially vary in X/Y directions, this also determines girder locations)
• Beam/Bay Spacing for floors
• Available beam span lengths
• Irregular Column spacing pattern
• Beam/Column sizes
• Area Load/Purpose of structural frame
• Framing material (steel, reinforced concrete, mass timber)
• Earthquake Seismicity Rating
• Evaluators
• Number of columns used
• Number + Length of beams used
• Beam deflections
• Required Footing sizes to carry load
• Structure Weight
• Architect satisfaction/workability
• Construction complexity
• Carbon footprint of material used
• Column Deflection
• Most Important Tradeoffs to Consider
• Longer bays = longer beam lengths, which will increase beam and slab deflections, lowering structural performance, but will have less construction joints required
• Fewer columns = better architecturally for more open floor plans, but affects amount of load per footing, increasing costs/material
• Material such as mass timber = lower carbon footprint material but may need more volume/cost of material to achieve similar structural performance as steel/reinforced concrete
• Construction complexity based on number of connection joints will drive up construction costs, but will provide more framing and increase structural performance
• Architectural Design - Facade
• Design Variables
• Ratio of window area to wall area
• Glass material type/opacity
• Evaluators
• Amount of heat entering window
• Glare from glass material
• Material cost
• Views for occupants
• Most Important Tradeoffs to Consider
• Higher ratio of Window to Wall area will provide more views, but increases amount of heat gain
• Glass material type with more efficient glazing will increase material costs
• Sustainability - Natural Ventilation
• Design Variables
• Area of Window that can be opened
• Floor plan area with window access
• Location of window ventilation in room
• Evaluators
• Less energy usage for AC/Heater
• Air quality
• Outdoor noise
• Air exchange rate, how much actually enters the building
• Most Important Tradeoffs to Consider
• More ventilation from window area lowers energy use but increases noise intrusion
• More ventilation from wind can increase the air exchange rate, but also cause more air pollution indoors depending on the structure’s location
• Building Usage Distribution
• Design Variables
• Zoning areas as Public or private spaces
• Amenity Sharing locations
• Zoning types in Vertical direction
• Evaluators
• Structure Revenue
• Noise transfer between spaces
• User satisfaction
• Physical Accessibility
• Structural Design efficiency
• Most Important Tradeoffs to Consider
• More public spaces may introduce more revenue, but create additional noise for people in allocated private spaces
• Shared public spaces improve interaction between users of the structure but decrease privacy
• Public spaces increase revenue but will cost more to construct due to higher structural demands
• Urban City heat distribution
• Design Variables
• Vegetation coverage outdoors
• Tree Density
• Spacing between neighboring structures
• Pavement material type
• Evaluators
• Pavement temperature
• General temperature outdoors
• Plant diversity
• Plant water usage
• Housing Density
• Tradeoffs
• More vegetation coverage provide more shade and cooling but require more water to maintain
• More spacing between structures allow more airflow, but decreases rent revenue and housing density

I decided to work with the Structural Framing design decision since I have more background in this area.

Objective: The goal is to create an ideal framing model that will minimize structural weight (and therefore, construction and material costs) while maximizing open floor plan area and structural performance.

Model: The model will be of a 1-story frame, where the constant will be its footprint area and structure height. The beams, girder, and column layout will be shown in this model to see how the spacing affects the overall shape of the building.

Design Variables: The 4 design variables will be maximum column spacing, maximum beam spacing, area loading values, and steel section type.

Constants: The dimensions of the overall structure, which will will be constants. The steel will also all have an Elastic Modulus of 29000 ksi. An dictionary list of 5-6 sections is provided and can be chosen from. While the steel section itself is a design variable, a dictionary of the moment of inertia and weight of each section will be constant and set to real numbers from ASCE. The same section will be applied to beams, girders, and columns for simplicity.

Evaluators: The 4 Evaluators will be beam deflections, structural weight, largest area between adjacent columns (to analyze how open the space is), and construction complexity based on number of member joints. The beam deflection is analyzed as a simply supported beam with the maximum tributary distributed load applied. The structural weight will be calculated based on the total length of all the structural members multiplied by it’s weight per foot based on the section type. The largest area between columns is based on the final column spacing. The construction complexity is based on the total number of connections required to build the final structure.

Sample Input

• The screenshot of the Scatterplot or Parallel Coordinates Graph illustrating the tradeoff that you chose to model and study.

• Provide a brief explanation of what’s being shown in the Scatterplot or Parallel Coordinates Graph and how the tradeoff being illustrated would impact the design decision. What would you do with this info?

The scatter plot above shows all 4 evaluator outputs based on minimizing every design variable except for the amount of open area in the structure. There is a trend between the X and Y axis where higher deflections will end up with a smaller total number of construction joints. There is a decreasing parabolic trend between the two, where some studies can provide smaller deflections but still have relatively small number of construction joints. The size of the points are used to indicate the maximum open area. It can be noted that the largest maximum areas occur at points typically with larger deflections. The structural weight is shown by the color, where the lowest weight occurs at red values, while heavier structures are shown in the bluer color range.

This can best show the tradeoff of how longer column spacing/bays will increase deflections and lower structural performance, but also show that increasing the number of joints and members a small amount can drastically improve its structural performance. From this, I would run more studies with more spacing variations to see if I can find more points that sit in the bottom left corner of the scatter plot which will better the stuctural performance while decreasing the construction cost. It would be helpful to find a balance between the size of the scatter points which can maximize the open area and make the structure more easy to work with architecturally.

• Dynamo Study Graph