CENTRE SQUARE STATION Reimagining Transit and the Public Realm in the Heart of Philadelphia Chris Hytha
Adviser Katie Broh
CONTENTS 1. SITE ANALYSIS
1-6
6. SITE
15-16
2. RESEARCH
7-8
7. STATIONS
17-20
3. INITIAL REVIEW
9-10
8. LOVE PARK
21-22
4. PRECEDENT
11-12
9. HELIOSTAT
23-24
5. DESIGN OBJECTIVES
13-14
10. SUSTAINABILITY
25-26
SITE ANALYSIS TRANSIT
With its robust network of above and below grade transit infrastructure, Center City Philadelphia became the focus of my study. I identified a site on the west side of City Hall with an opportunity to connect four major transit stations, as well as capturing the bus corridor of JFK. Over 110,000 people arrive in Philadelphia via transit through this site.
Love Park
Municipal Plaza
Site Area Two - Three Penn Center Dilworth Park
City Hall
GROUND LEVEL - EXISTING
Parking Suburban Station Penn Center Concourse
Concourse City Hall Foundations
Building Basements MFL Mezzanine
CONCOURSE LEVEL - EXISTING
Commuter Platforms
KEY BUS RAIL BIKE 0’
250’
500’
1000’
Trolley Stop Loading Dock MFL Platforms
Trolley Track BSL
Trolley Stop
TRACK LEVEL - EXISTING
CHRIS HYTHA 2021
2
Survey - MFL + BSL Mezzanine
Survey - Connection between BSL and MFL
Love Park
Parking
Loading Dock
Trolley / MFL Tracks
One of the first steps of the project was understanding the complexity deep under the streets around City Hall. I spent several days surveying the subway and concourse system to develop a 3D model of the existing conditions.
Suburban Station
THE UNDERGROUND
Underground Service Road
SITE ANALYSIS
CHRIS HYTHA 2021
Concourse Under Broad St
Trolley Track
BSL City Hall Station
MFL / BSL Interchange
MFL / BSL Mezzanine
Dilworth Subway Entry
Trolley Stop
Trolley Mezzanine
Clothes Pin Sculpture
MFL Mezzanine
Concourse Entry
Commuter Tracks
MFL 15th Street Station
Three Penn Center
Two Penn Center
REVEALING THE UNDERGROUND
Looking North East
4
One Penn Center (Suburban Station)
Commuter Rail Tunnel
Viaduct (Chinese Wall)
Train Shed
Head House
SITE ANALYSIS HISTORY 1880 BROAD ST. STATION
1930 SUBURBAN STATION
An elevated viaduct once brought commuter trains into the heart of Philadelphia. A grand head house abutting City Hall designed by Frank Furness acted as a gateway to the city. The station provided a dignified way to arrive, but had its technical problems. Trains had to pull in, then back out, which added time to the schedule. The viaduct divided this portion of the city, and earned the name "The Chinese Wall."
A solution to the problems of Broad Street Station came in the form of a new Pennsylvania Railroad HQ building atop a new subterranean rail tunnel and platforms. While the station was now more efficient, the grandeur and sense of arrival found in the old head house was now lost and replaced with cramped spaces tucked under the city streets.
Hotel
Underground Concourse
Oenn Center 2 and 3
Office Tower
Open Air Concourse
Reclaim Centre Square
1950 ED BACON CONCEPT
1960 PENN CENTER
Eventually, the Broad Street Station viaduct was demolished, and a huge swath of the city became ripe for development. Ed Bacon worked on a plan for an open air concourse that allowed pedestrians to circulate under 16th and 17th street. He focused on the arrival to City Hall, with the rhythm of light and shadow traveling under the three office towers. At the east end of the concourse, visitors rise into a new Centre Square plaza.
The Pennsylvania Railroad disregarded most of Ed Bacon’s plan, opting for an EW orientation for the office towers, and an entirely underground concourse that became more of a labyrinth than a civic experience. "One entered the city like a god. One scuttles in now like a rat." -Vincent Scully (Describing Penn Station NYC) CHRIS HYTHA 2021
6
RESEARCH
THE CASE FOR PUBLIC TRANSIT
$1,000
Automobile infrastructure has become primary to nearly everything else in our built environment. Highways tore through neighborhoods in cities, leaving public transit infrastructure underused and underfunded. Despite the dominance of cars, there are still many benefits to using alternative transportation. These benefits include cost, safety, space, and environmental impact. What happens when transportation modes other than the car are prioritized?
ANNUAL COST SEPTA COMMUTE
$8,698
AVG. ANNUAL AUTOMOBILE COST
TRANSIT FATALITIES
DEATHS PER 100M PASSENGER MILES
KEY CAR BUS RAIL 0.6
0.4
0.2
0 2013
2014
2015
2016
2017
2017
DISRUPTION IN EARTH’S CARBON DIOXIDE FLUCTUATION
BIKE - 0 lbs CO2 PER PMT
ATMOSPHERIC CO2 (PPM)
Date from NASA - https://climate.nasa.gov/evidence/
480 440 400 360 For millennia, atmospheric carbon dioxide had never been above this line
320 280 240 200 160 800,000
700,000
600,000
500,000
400,000
300,000
200,000
100,000
0
YEARS BEFORE TODAY (0=1950) TRAIN - 0.28 lbs CO2 PER PMT
C02 IN THE ATMOSPHERE AND ANNUAL EMISSIONS
420
40
400
35
380
30
360
25
340
20
320
15
300
10
280
5
260
0 1750
CAR - 0.87 lbs CO2 PER PMT
1780
1810
1840
1870
YEAR
1900
1930
1960
1990
CO2 EMISSIONS (BILLIONS OF TONS)
BUS - 0.54 lbs CO2 PER PMT
ATMOSPHERIC CO2 (PPM)
NOAA Climate.gov
2020
CHRIS HYTHA 2021
8
INITIAL REVIEW
Preliminary bike highway axon
WINTER 2020
My initial idea for the project was to establish a pedestrian and bike highway to encourage more sustainable modes of transportation. This highway, highlighted in orange below, was intended to make meaningful connections to transit by weaving through the city’s layers and opening up Market Street.
MAIN TAKEAWAYS The sentiment at the review was that the project is based on fundamentally flawed ideas in urban planning. It is dangerous in a city to segment and divide the street plane, and putting cyclists on an elevated highway removes them from the activity of the street. With this feedback in mind I decided to take a new approach moving forward.
Bike highway weaving under an open Market st.
View from Market Frankford Line.
Separate pedestrians and cars.
1.
2.
3.
4.
5.
6.
A typical urban street is unfriendly to pedestrians and bikes. There is a clear priority given to automobiles, which creates unsafe and unpleasant conditions for other users.
The only way to make a truly safe zone for cyclists is to entirely separate them from cars. My proposal is for an elevated bike and pedestrian highway.
A progressive urban street begins to consider cyclists with the introduction of a bike lane. In theory separating uses in this way creates a safer environment.
With the advent of a safe way to travel without a car, travel lanes below could be reduced to provide space for connections to public transit as well as rain water management features.
Unfortunately, even with a bike lanes, streets are unsafe for cyclists. There are several points of conflict such as entries to parking lots, cars turning, and trucks blocking bike lanes.
New buildings are integrated into this new elevated public realm to create more connections between above and below.
CHRIS HYTHA 2021
10
PRECEDENT
BARCELONA SUPERBLOCK LOCATION DESIGNER DATE COMPLETE
Barcelona Salvador Rueda In Progress
The car has become primary to all other modes of transit, and this takes its toll on cities. Barcelona suffers from extreme congestion, unhealthy air, and noisy streets. This proposal aims to solve these problems by making the car secondary.
BIKE INFRASTRUCTURE With reduced traffic speeds and smaller lane one way travel for cars, a safer space for biking is created.
BEFORE
AFTER
Barcelona is planned as a ridged grid. Currently, vehicular circulation travels between each block. Intersections contain street parking. Travel by car is encouraged in this model at the expense of pedestrians.
Nine city blocks are grouped together to create a Superblock. Heavy car traffic is directed to the perimeter, and interior roads are closed to through traffic. Interior intersections become public amenities.
CREATE GREEN CORRIDORS
IMPROVE BUS ROUTES
At the center of Superblocks streets are narrowed to give back space to the pedestrian.
As part of Barcelona’s transit overhaul, they have an ambitious plan to rethink their bus service.
PRECEDENT CENTRAL STATION LOCATION ARCHITECT DATE COMPLETE
Rotterdam, NL Benthem Crouwel March 2014
What does it mean to arrive in a city? This project creates an intentional arrival sequence through a grand hall with a sense of civic scale and dignity. The building becomes a gateway to Rotterdam, aligning with a pedestrian friendly green axis that draws you into the city. This project is also interesting because it services nearly the exact same amount of travelers per day as my site, 110,000.
Site Plan
View of Central Station from above.
Central Station main hall.
CHRIS HYTHA 2021
12
DESIGN OBJECTIVES
1.
Create a dignified arrival to center city with a sense of civic scale and grandeur prioritizing pedestrians over automobiles.
The Oculus NYC.
2.
Establish visual, physical, and experiential connections between the center city transit network and the activity of the city streets.
Berlin Central Station.
3.
Integrate with the surrounding context, celebrate city hall, and connect with the important axis of the Ben Franklin Parkway
City Hall Philadelphia.
ARRIVAL PLAZA New Centre Square
CHRIS HYTHA 2021
14
SITE
PLANNING William Penn’s original plan for Philadelphia called for 5 squares. Centre square, the current site of City Hall is the only square now occupied by a large structure. Penn’s intent was for a public plaza in the heart of the city bounded by civic building. The new site plan reinterprets Centre Square as a pedestrian centric superblock and new multi-modal transit hub linking buses and rail transit.
Site plan sketch iteration 1
Site plan sketch iteration 2
Site plan sketch iteration 3
BIKE
BUS
CAR
A 0.8 mile trail circles the new Center Square to extend the recreational use of the parkway as well as provide much needed bike infrastructure in center city.
JFK is a primary bus route, made more efficient by the elimination of cars. Buses have designated loading and unloading zones throughout the superblock.
The existing one way circulation around city hall is extended to include the Municipal plaza, Love Park and the adjacent site.
SITE PLAN
New Centre Square 0’
75’
150’
CHRIS HYTHA 2021
300’
16
Looking west from MFL arrival plaza.
STATIONS SUBWAY / TROLLEY
On the south side of the site the commuter rail train shed reaches up into the sky with its light tectonic truss system. Here on the north side, the project sinks down to reveal the subway lines and a heavy concrete structure that is of the earth. Directly from the train platforms visitors are greeted with views out to the city, diffuse reflected natural light, and passive ventilation.
RELATION TO CONTEXT
STRUCTURE
The arched forms pick up on arches across the facade of City Hall. The image on the right demonstrates a foreground quality of the vaults. They are intended to be simple so that City Hall remains the focus.
The parabolic vault concrete structure is an inherently structural shape to provide high ceilings possible to contrast the existing low corridors. The incredible quality of reflected light (see heliostat page) was a driver of the structure. The vaulted forms catch and diffuse light to create a memorable entry experience from the subway lines.
MATERIALITY The vaults are clad in broken tile and glass to create an uneven and sparkly human scaled finish to further animate the reflected light cast down into the station.
Looking south in new BSL. station.
Secondary reflectors in plan.
Secondary reflector section
Isometric vaulted structure. 18
A new commuter rail train shed creates a civic and dignified entry experience, connects above an below with views and light, and celebrates a view of city hall from the train platform. A public green lawn occupies the top of the train shed creating a multi-functional structure. The train shed aligns with two major axis down JFK to 30th Street Station and down the Ben Franklin Parkway to the Philadelphia Museum of Art.
View from commuter rail platform.
Pedestrian circulation from station.
Market Meadow
COMMUTER RAIL
Market St.
Market Frankford Line
STATIONS
Existing Parking
Philadelphia Museum of Art
Commuter Rail Train Shed
Love Lawn
30th Street Station
Septa Bus Route
Heliostat Array
City Services
N/S SECTION PERSPECTIVE
Looking West
0’ 30’ 60’
CHRIS HYTHA 2021
120’
20
LOVE PARK REIMAGINED
The new green lawn looking over the parkway provides a elevated experience of the Parkway. Looking back towards City Hall, the project is intentionally left as a simple green backdrop to maintain the celebrated view of City Hall from the PMA. The three vignettes to the right demonstrate the flexibility and variety of uses envisioned for the site.
Looking NW down the Parkway.
TYPICAL DAY On a typical day, the green lawn becomes a place of pause to watch the city go by. On spring and summer days, visitors relax and picnic in the park, while taking in the view down the parkway.
SLEDDING The urban landscape of Center City Philadelphia is devoid of natural hills. This park creates an opportunity for sledding, slip and slides, or just rolling down through the grass!
EVENTS For special events, the hill can become an assembly space that fits thousands. Events could include shows, movie screenings, or music festivals. The open space of the lower lawn can house temporary stage / event structures.
CHRIS HYTHA 2021
22
HELIOSTAT DAYLIGHTING
One common trait of the grand train stations of the past, like Penn Station in NYC, is access to natural daylight. On the north side of the site, southern daylight penetrates to the platforms. On the south side, an array of motorized sun reflecting panels track the sun during the day to reflect beams of natural daylight down into the subway lines.
Section perspective looking west.
SECONDARY REFLECTORS Beams of light from the primary mirror array shine down to the open face of the subway lines. To avoid unwanted glare, and to bounce light deeper, there are a series of secondary highlighted in blue above. These suspended planes create a connection between interior and exterior. Light is bounced up into the vaulted ceiling, and the semi-transparent reflectors create diffuse illumination below.
Market St.
MFL Subway
Secondary reflector section diagram.
Light From Heliostat
Secondary Reflector
Heliostat impact on interior space - Morning
Experience of Heliostat from Street Heliostat impact on interior space - Noon
INTERIOR EFFECT
EXTERIOR EFFECT
The special collaboration programming of the office building is positioned behind the heliostat. During the morning, the heliostat acts as a screen, casting dynamic shadows on the ground. In the afternoon, the heliostat can bounce light up into the ceilings of the collaboration space.
The experience of the heliostat from the street is intended to connect pedestrians above with the rhythm of transit. The mirror panels move to illuminate either the MFL or BSL when trains arrive. From above, this rhythm is experienced, as the reflector panels move and glisten in the sun. The heliostat is not only functional, but is a public work of art to animate the arrival plaza. CHRIS HYTHA 2021
24
SUSTAINABILITY DIAGRAMS
The primary sustainability objective is to reduce the reliance on cars as the primary means of travel. Additionally, rainwater is not only managed, but is designed to be experienced through the site. Rocky channels cutting through the site direct rainwater to a central occupied rain garden. Grates in the plaza allow rainwater to trickle down select feature walls of the subways below to experientially connect above and below.
Occupied rain garden catchment diagram.
PASSIVE VENTILATION The open design of the subway stations allows for passive ventilation.
RAINWATER Rainwater is used experientially connect below grade to the world above.
DAYLIGHT Daylight is reflected down from the heliostat to the left, and washes down a textured stone wall to the right.
CHRIS HYTHA 2021
26
Chris Hytha Email - Chris.hytha@gmail.com Phone - 484-753-2848 Instagram - @Hytha.cg
Drexel Architecture 2021