Site Analysis

I drew this series of site analysis diagrams earlier in the week. Each one reveals specific characteristics of the site. My hope is that these will drive my decisions when designing the park.

Hydrology

As discussed in an earlier post, I did a grading plan for the proposed park, yielding the necessary clearance for the interstate below and graded as flat as possible. The park can not go any lower than that grading, but it can build up from there if needed. Using that plan I drew a hydrology diagram showing where the water would naturally flow and collect on the deck. Again, this will likely change as the park is designed, but this is a good starting point. Not the lowest points on each deck. These may be logical places for water collection.

Pedestrian Circulation

This diagram shows the pedestrian circulation through and around the site. I used thicker lineweights to show the routes most traveled, particularly the East/West corridors. The surrounding buildings are either existing or proposed. The proposed buildings are from Erin Gray's design on the site last semester. The dashed lines represent the deck where it will not be on grade with the topography due to interstate ramps or lower terrain. The solid lines representing the deck are where it will be on grade with the existing topography. The key point to this diagram are that the entrances to the park mostly fall along the streets and at the corners of each deck.

Vehicular Circulation

This diagram shows the vehicuar circulation around the site. It includes the city streets, the interstate and the ramps leading to the interstate. Since I have been staring at these maps for most of the semester, I have a good understanding of how the ramps work. This diagram was drawn so that people who have not spent as much time with the project can gain a quick understanding of the flow of traffic arround the site. It also includes the additional roads proposed by Erin Gray last semester. Key points from this are that this park is surrounded by ramps. The streets running parallel to the decks are one way streets, which is easir for pedestrain crossing. The streets running perpindicular to the decks and running through the park are much busier. Like the pedestrain circulation, there is heavier East/West flow. Broadway is the busiest of these crossing streets and will also host the new BRT line. This will certainly be considered in the design. Division and 12th South are less traveled and have only 4 lanes.

Primary Structure

Here we go again. I think I touched on this as I was making the initial deck grading. This project would require a team of structural engineers. I am not a structural engineer, nor am I an architect. I do want to have enough understanding of the structure to draw up the basics. I know there will be verticle walls running parrallel to the interstate to serve as beams. Upon these walls will be the joists, which will run perpendicular to the interstate. This diagram shows the primary walls running parallel to the interstate, one on each side and one down the center between the lanes. This configuration does allow for on and off ramps.

Tree Planting Zones and Secondary Structure

The diagram above shows not only the primary walls, but also some secondary walls that would allow for areas between the outermost interstate lanes or ramps and the city above to be backfilled with soil or perhaps used for water storage. The primary purpose of this would be to allow for the planting of larger trees. This may be difficult on much of the deck due to shallow soils. The green hatching represents areas that would be suitable for larger tree plantings with the additional structure and backfill. The section drawing helps illustrate the idea. The solid green represents areas suitable for large trees simply by backfilling the primary structure.

The joists would look something like the option on the left. The option on the right allows for more soil depth and tree plantings between the joists, but it will cause problems with freezing. The option on the left also allows for free movement of water along the deck. Loads have yet to be calculated and are dependent on the design.

 

Site Model Finally Finished

I finally got the buildings put onto the site model. I also made pieces that place over the interstate to represent the deck. I wanted to get some pictures up of the completed version. The site model gives a instant visual understanding of the current lay of the land. It also gives anyone who is unfarmiliar with the project an instant understanding of what is happening. 

Although it is at 8 ft. contours, it still gives a good picture of how the ramps come to and from the interstate below. Perhaps the aerial image helps show some detail where the large contours are lacking. Hopefully I will have time at the end of the semester to make some final models of the actual designed park to place into the site model instead of the blank, white deck that is there now.

moving forward

I think my next steps are to layout the structural supports for the park and to start master planning. I am not how the structural elements will fit together, but the Woodall-Rogers Park in Dallas shows 13’ box beams spaced 7’ apart. This aerial image shows the beams being laid across the interstate. Simple enough, but what about the curve in the interstate between 12^thSouth and Division?

 I will also start sizing some of my programming elements and seeing how things fit. Where does pedestrian circulation go? These will help form the basis for the master plan, which I would like to present to my committee on trace paper by early next week.

grading

I know from my site model and from visiting the site that the engineering of the park will be a little trickier than the Woodall-Rogers Freeway park in Dallas. The park in Dallas is flat and straight. The terrain in Nashville, typical to Middle Tennessee, contains rolling hills. There is also the issue of surrounding ramps, which I have expressed concern with before discussing the possibility of these ramps limiting accessibility to and from the park. There must be proper clearance below not only for interstate traffic, but also for vehicles exiting and entering the highway. I am by no means a structural engineer, but do need to have a good understanding of how this would work. I will likely learn more during my next committee meeting (3 architects, 1 landscape architect) but for now, I am using the thickness of a parking garage floor I measured (38”) with the required bridge clearance for an urban interstate (14’…I used 14.5’ for a little extra room). This comes to 17’8”. I rounded up and decided the deck needs 18’ from the surface to the interstate below work.

 My site map only has 4’ contours, so it is not exact. I feel that I now have a good idea of where how the ramps will affect the deck above. Bottom line is that there is less room for these ramps than I had originally thought. The drawing below shows where the deck can occupy space without regarding the ramps. As I begin to conceptualize the master plan, I will decide if the ramps should be regraded or not.

As stated before, the rolling terrain will have to be dealt with. My next step was to draw out how the park would be graded to make the existing grade transitions at the edges of each deck as smooth as possible. The deck grading could be thought of as a base map for the deck. It can be modified of course, but this shows the smoothest transitions possible without changing the elevations at each corner or each of the sections. Certainly, regarding at the edges will probably be desired in some areas. The green represents the deck. Solid lines are at existing grade while dashed lines represent edges that are not at grade. Again, this is partly due to the existing topography and partly due to the ramps at the edges. Pedestrian access can only be gained where the deck is at grade with the existing topography, mostly at the corners for three of the sections.

Development Moments

In learning about the history of the city and the site, I have discovered some old maps from various sources. I have assembled some of these maps into a diagram series that shows development moments through time in Nashville. The series focuses on transportation and building density and development as perceived. Together the maps and the diagrams show a shift in transportation from the river, to street trolleys and railroad, to the pikes, to the interstates. The development shows a very dense city in the 1860’s becoming increasingly decentralized through the 20^th century until the height of sprawl we see today. But we are seeing people moving back into the city with a downtown resurgence. But where will this development take place? Historically, development has most heavily followed the East West Corridors from East Nashville, through town and into midtown. Future development predicts an increase in centralized living and a need for increased growth of the city across the interstate loop along the same corridors growth has followed historically. This deck park would help to facilitate this growth and make downtown living more appealing to people considering moving from the suburbs to the city. This park would serve its growing community.

Sketches

I attended a design sketching workshop last weekend. The leader of the workshop went over some techniques for the first hour, and then asked us to sketch whatever came to mind. Of course, I sketched a deck park. I didn’t have a scale or specific dimensions, so proportions are not accurate, but it shows the general idea. I also came up with an interesting idea that I might use in the design of the park. What if I could use the vibration, sound, and movement below to create a reaction above the park? The sailboat looking object I sketched could be a way of channeling the vibration below into through the large metal shape. This vibration could cause ripples in the surrounding water on calm days.

The Foundry Event

The event at the foundry was an opportunity for graduating students to share their semesters work to this point with local professionals. This proved to be a valuable experience. I was able to have a nice conversation about my project with a talented landscape architect early in the evening, before things got too busy. My design decisions to this point are simply programmatic, based on context and demographic information. I think I am on the right track with my programming ideas, but it was suggested that perhaps I don’t be so dry about how I word these ideas. Perhaps I’ve spent too much time in the architecture building lately. It was also suggested that I produce a master plan for the entire park, and focus a detailed design on one section of my choice. This would prevent me from just doing a mediocre design by taking on too much.

I also got some good information on the Rose Kennedy Greenway from someone who has lived in Boston. This person suggested that perhaps I am being too critical with my assessment, and I think this is probably true. I guess that is to be expected from a former Bostonian. We did agree that some sections of this park serve the community better than others.

As far as the rest of the evening went, it was great to get some work pinned up. I also got to show off the site model I built (which I’m quite proud of, in case you couldn’t tell). I finished the buildings and made some inserts to place over the interstate, representing the park. The model served as a useful tool in gaining a quick understanding of the concept and the site.

The event at the foundry was an opportunity for graduating students to share their semesters work to this point with local professionals. This proved to be a valuable experience. I was able to have a nice conversation about my project with a talented landscape architect early in the evening, before things got too busy. My design decisions to this point are simply programmatic, based on context and demographic information. I think I am on the right track with my programming ideas, but it was suggested that perhaps I don’t be so dry about how I word these ideas. Perhaps I’ve spent too much time in the architecture building lately. It was also suggested that I produce a master plan for the entire park, and focus a detailed design on one section of my choice. This would prevent me from just doing a mediocre design by taking on too much.

I also got some good information on the Rose Kennedy Greenway from someone who has lived in Boston. This person suggested that perhaps I am being too critical with my assessment, and I think this is probably true. I guess that is to be expected from a former Bostonian. We did agree that some sections of this park serve the community better than others.

As far as the rest of the evening went, it was great to get some work pinned up. I also got to show off the site model I built (which I’m quite proud of, in case you couldn’t tell). I finished the buildings and made some inserts to place over the interstate, representing the park. The model served as a useful tool in gaining a quick understanding of the concept and the site.