Structural Framing Systems

Journal Entry For
Module 8 - Structural Framing Systems
Created
Feb 20, 2023 7:30 PM
Created by
Yuuki Tanaka
Last Edited
Mar 1, 2023 12:20 AM
Scored
Your Name

Grids (Level 1)

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Structural Framing Elements

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Model Coordination Views

Level 1

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Level 2

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  1. Your overall strategy and the features of the structural system
  2. My overall strategy when designing my structural system is to encourage the participants to see the design. As a sustainable design exhibition center, displaying the structural system and allows the attendees to pay attention to that which most people do not pay attention to (aside from civil engineering students). At the same time, I wanted to have a lot of open space and ensure that occupants did not feel confined by a bunch of columns. As a result, I chose a combination of wooden beams & girders with steel columns. The use of glulam for the visible, the use of steel for the “invisible,” although some columns are not embedded in walls. The rectangular nature of my building was conducive towards having a grid system that allowed me to put columns within walls. Features of the structural system include structural walls for the elevator shaft and restrooms (the cores of my building), wooden beams & girders, steel columns, pile caps, a concrete SOG, and concrete slabs on metal decking. Since my location is in California, I wanted to ensure I was conservative in the structural design, therefore you will notice that the beams and girders are quite thick in dimension (6.75” x 30”). Furthermore, every column on the first floor has a pilecap attached to it at the bottom, and the structural walls have bearing footings too, additional examples of structural fortitude. Although I wanted to minimize concrete, it’s thermal properties to retain heat and the fact that it’s a proven material to provide a solid foundation ultimately led me to incorporate it into the design of the structural system. Yes, cement has a substantial carbon impact, but there are ways to reduce its footprint such as reduced slag-mixes and low-carbon/carbon-negative aggregate. Pile Cap:

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  3. The material and framing system selected
  4. Columns: W10X49 ASTM A992 Steel. Typical wide-flange steel selected due to accessibility & familiarity with construction. There are a lot of contractors out there that can install this material but also, a sustainable material since it’s 100% recyclable and can be comprised of majority recyclable material. Wide flange steel:

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    Beams & Girders: 6.75 x 30 Glulam-Western Species. Glulam was selected for its superior durability and moisture-resistant properties compared to general timber, and western species chosen since my location is in California, USA. The dimensions, admittedly, were not chosen from structural analysis, but rather, a conservative estimate based on watching Glenn’s videos. Glulam:

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    Framing System: Column, beam, girder system. Girders are spaced at 6’ apart based on observing 220A videos.

  5. The locations of structural columns and major framing elements
  6. Location of the structural columns were designed to be embedded in the walls as much as possible, aside for the middle of the exhibition center. If anything, the columns that are in the middle of the exhibition center can serve as an exhibit in themselves. Attendees can learn a tidbit about what designers have to consider when designing the structure of a building and having an exposed column gives an example upfront.

  7. Any special structural challenges
    • Maintaining egress and access to outdoor views
      • I had to shift my architectural design more than a couple of times after realizing a column was blocking a door, or the girders were going to block a window. Using structural steel helped because I had the option of spacing columns a little bit past 30’, which gave me more flexibility in spacing. I realized through this module the importance of planning grid line placements very thoughtfully before including them in the model. The elevation view below gives a good example of the access to window views. I also changed my stairwell from being one right in the middle of the exhibit, to one off to the side of the elevator. Doing this gave me more flexibility for column placement and I realized my prior choice wasted a lot of space.
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    • Too much versus too little
      • As my building is in California and near the Hayward fault, I had to be mindful of creating a system that would ensure seismic resilience and up to design code, while also ensuring that the architectural features of my building wouldn’t be compromised. I initially wanted to have my entire structural system be comprised of wood, but the limitation in column spacing ultimately encouraged me to use steel instead.