Transcript Document 7243692

ISLAND TEAM 2001
SIGHT LINES
SAN RAFAEL
BRIDGE
BERKELEY
BAY BRIDGE
SITE DEVELOPMENT
CALIFORNIA SITE /
VISUAL CONNECTIONS
FLORDA WEATHER /
ECOSYSTEM / SOIL
FUSION CONTEXT CALIFORNIA + FLORIDA
90 MILE WINDS IN A 40 nm RADIUS (RELEASES
1.21.5 x 1012 WATTS DURING WIND
GENERATION)
STRENGTH AND FREQUENCY OF
HURRICANES WILL DICTATE
COMPROMISE BETWEEN
TRANSPARENCY AND SAFETY
MAJOR MATERIAL / CLADDING CONSTRAINT
beach sand
•rocky beach at
base of cliff
•unstable in a storm
•poorly suited for
building
tocaloma-mcmullin complex
•moderately deep and well drained
•mat’l derived from sandstone and shale
•depth to bedrock: 20-40 inches
•problems with runoff in water erosion
SITE SOIL CONDITIONS
general gravity loads
liveload:100-psf (assembly areas); 50-psf (office areas)
deadloads:
•flat roof
20-psf
•floor (4.25”LWC, decking, flooring,
ceiling, fireproofing)
65-psf
•exterior cladding
20-psf
•girders
100-plf
•beams
60-plf
wind loads:
•per UBC 1997, section 1621.2, method 1
•p= Ce x Cq x qs x Iw
•qs: 31.0-psf
•Iw: 1.0
LOAD CONDITIONS
A
•transparency, the blurring of exterior / interior
•full exploitation of site / climate
•foster faculty / student interaction
E
•balanced lateral force resisting system
•stiff foundation connected to bedrock
•least intrusive structural system
C
•palm tree protection
•high water table
•construction on campus
•transportation
TEAM GOALS
A
B
plan 0.0
plan 10.0
•radiating shear walls
•void in ground plan (A)
•courtyard at entry (B)
Plan 20.0
EXISTING PLANS
PLAN 0.0
•insert gym into
unused space at
ground level
•soil conditions
(rock) make
excavation difficult
•possible water
issues
INFILL OF GYMNASIUM
•insert cafeteria into entry court and
strengthen previous year’s structural
articulation with extension of shear
walls
2000 island team image
continuation of shear
walls into entry court
CAFETERIA INSERTION
REDEVELOPMENT OF ENTRY SEQUENCE
architect’s sketch of structural approach to
hanging cafeteria volume
DESIGN DEVELOPMENT DIALOGUE WITH E / C
led to :
One step in the iterative
process of design
development…
construction and
structural
development dialogue
in synch with
architecture
DESIGN DEVELOPMENT DIALOGUE WITH E / C
articulation of truss structure
resolves façade / creates module
MEP considerations
lead to ‘plug’ concept,
whereby all services to
cafeteria are
expressed in the
exterior
E/C DEVEL. INFORMS VISUAL ARTICULATION
suspended cafeteria
•clean connections
•reliable LFRS
•avoid structure racking
underground gymnasium
•strong soil retaining wall
•handle large ceiling loads
•decrease clear height
STRUCTURAL VISION & CONCERNS
cafeteria total load: 254-kips
load path
•floor beams
•truss elements
•roof elements
•suspension beam
•foundation
gymnasium: total roof loads: 225-psf
•use w14x68, 33’ span
GRAVITY LOADING
cafeteria
windward wall pressure: 36-psf average, 582-sf
leeward wall:
23-psf
roof and parallel walls:
33-psf
load path
•building exterior
•roof or floor diaphragm
•suspension or floor beam
•MR foundation
gymnasium: lateral loads
•surcharge load
•active pressure load
LATERAL LOADING
option 1 :
option 2 :
members
•10x10, 3/8” tube sections
•w10x15 sections
•5x5, 1/2” tube sections
BOX SYSTEM
PHMRF
strengths
•clean connection
•ease of construction
•allows precast
weaknesses
•limited applications
•lack of redundancy
box sections
strengths
•easy construction
•inexpensive
weakness
•material disconnect
SUSPENDED BEAM SECTION
retaining wall
strengths:
•structural integrity
•possibly precast
weaknesses:
•long excavation time
•excavated material
soil nails
strengths:
•faster excavation
sequence
•less excavation
weaknesses:
•may not work with surcharge load
•dependant on skill of constructors
GYMNASIUM OPTION: RETAINING WALL
•option 1add cafeteria to l-shape building
•option 2 –
underground gym for square-shaped
building
CONSTRUCTION OPTIONS
mobile
crane
job trailers
mat’ls laydown
cafeteria
access for MEP installation
temporary easement
OPTION 1: SITE LAYOUT CHANGE
•cost change
4.4 M
New Cost
3.6 M
Original Cost
0
1
2
3
4
Million Dollars
•schedule change - minor change
OPTION 1: COST AND SCHEDULE CHANGE
5
•cost change
4.28 M
New Cost
3.46 M
Original Cost
0
1
2
3
Million Dollars
•schedule change – 2 week delay
OPTION 2: COST AND SCHEDULE CHANGE
4
5
A
E
C
FIRST CONCEPTS
GYM &
CAFETERIA
STRUCTURAL
OPTIONS
RETHINK GYM
LOCATION
PRECAST
PROPOSAL
CONSTRUCTION
SEQUENCING
DETAIL
CONNECTION
PROPOSAL
3D STRUCTURAL
MODEL
CAFETERIA
CONSTRUCTION
$
REDESIGN
SITE IMPACTS
-DRAINAGE
•subtractive geometries
of cube and sphere
•movement through
building choreographed
as a scenography
CONCEPTUALS
•interplay of masses
and transparency
•framed views
•full advantage of climate
through interior / exterior
ADDITIVE / SUBTRACTIVE DEVELOPMENT
STRUCTURAL RESOLUTION
Structural acrobatics were required to achieve
cantilever, over-emphasizing a minor design element
therefore: faculty offices moved within column grid
•strengthens sphere articulation
•improves views due to reduced structure
•frees up a significant part of the structural budget
for higher priority elements
PLAN REVISION
ADMIN.
OFFICE
FACULTY
OFFICE
AUDITORIUM
FACULTY
OFFICE
SMALL
CLASS
STUDENT
OFFICE
SEMINAR
LARGE
CLASS
COMPUTER
LABS
PLAN REVISION
ADMIN.
OFFICE
FACULTY
OFFICE
AUDITORIUM
FACULTY
OFFICE
SMALL
CLASS
STUDENT
OFFICE
SEMINAR
LARGE
CLASS
COMPUTER
LABS
SECTIONS AND CORRESPONDING INTERIORS VIEWS
EXTERIOR SPACE
mesh grids on exterior
protect glazing and
retain office views
Materials / fenestration
overlaid grids create a vibration of light and
shadow
Light / Space Articulation
supporting the 3rd floor cantilever
bringing lateral loads to LFRS
balance: columns and open space
foundation system on dual soil types
STRUCTURAL CONCERNS
issues:
isolated LFR systems
problems with building response
OPTION: DUAL BUILDINGS
advantages:
•balanced system
•stiff frame
disadvantage:
•3rd floor / LFRS
connection
lateral load path:
•exterior cladding
•floor diaphragm
•drag strut
•shearwall or MRF
OPTION: OUTRIGGER TRUSS & SHEAR WALL
design iterations:
SYSTEM OPTION: CABLE STAY ARCH
design iterations:
SYSTEM OPTION: CABLE STAY ARCH
design iterations:
SYSTEM OPTION: CABLE STAY ARCH
SYSTEM OPTION: ALTERED FLOOR PLAN
SYSTEM OPTION: ALTERED FLOOR PLAN
SYSTEM OPTION: ALTERED FLOOR PLAN
SYSTEM OPTION: ALTERED FLOOR PLAN
advantages:
•avoid differential settlement
•weight reduction
•square footprint & column
spacing
disadvantages:
•not anchored to bedrock/soil
•sits on two soil types/strengths
•may have global settlement
problems
•thick and much reinforcement
FOUNDATION PLAN – PERFORATED MAT
•option 1
•mapping foundation
•shear wall and steel outrigger truss
•precast column and MRF
•option 2
•mapping foundation
•steel cable stay and truss
•precast column and MRF
CONSTRUCTION OPTIONS
•steel outrigger truss and
shear wall - regular
construction sequence
•steel cable stay challenge to the
construction sequence
CONSTRUCTION ISSUES
mat’ls laydown
temporary
partition
building
in use
building
under
const.
tower
crane
job trailers
palm
tree
SITE LAYOUT
main
road
temporary
easement
critical phase for cable stay construction
CONSTRUCTION ISSUES
$171.2/SF
total cost
COST COMPARISON
$175.6/SF
structure cost
excavatio
n start:
10/27/15
excavatio
n start:
10/27/15
cable stay:
non-critical
SCHEDULE COMPARISON
completion :
sep 26,
2016
structure
finish:
04/26/16
completion :
sep 12,
2016
structure
finish:
05/25/16
A
ASKS (E + C) FOR
“WISH LISTS”
E
C
RESPONSE
RESPONSE
FENESTRATION $
PROGRAM-BASED
LATERAL PROP.
PLAN
NEW CONCEPT /
OUTRIGGER SYSTEM
CANTILEVER $
SIM. PROG.
RELAT.
RENDERINGS
3D STRUCT. MODEL
SITE IMPACT /
CONSTR.
METHOD
COST /
CABLE STAY
REASSESMENT OF
SCHEDULE
CANTILEVER /
RELEVANCE TO
FOURTH
LATERAL / GRAVITY CONSTR. METHOD
ITERATION
SCHEME 1
CONCEPTUALS
+0.0
+20.0
+10.0
roof
student
faculty
auditorium
MASSING ORGANIZATION
student
entry
auditoriu
m
lab
class
faculty
lab
class
faculty entry
faculty
faculty
class
class
TRANSVERSE SECTIONS
internal ramps; view from faculty
internal ramps; view from entry
CIRCULATION
view from student entry
structure frames views
LIGHT AND SPATIAL ARTICULATION
glazed interstitial
members
black synthetic
membrane
MATERIALS / FENESTRATION
concrete
structure
supporting the 2nd & 3rd floor
cantilever
large retaining wall
developing a foundation
STRUCTURAL CONCERNS
total lateral load: 170-kips
Plan View
total lateral loads: 134-kips
elevation view
total moment: 1100 k-ft
Plan View
LATERAL LOAD PATH
advantages
•clean connections
•can be blended into structure
disadvantages
•unusual construction
•large moment on shear wall
•local failure will be disasterous
max. chord force:
147-kips tension
total wall moment: 15,750-kft
CANTILEVER OPTION: CABLE STAY
advantages:
•rigid supports
•common materials
disadvantages:
•need large forms for
concrete
•large dead loads
sizes:
•wall width: 8-inches thick
•weight: 37-kip load each
system description:
•two rigid walls holding the platform on each side
•dual use as room walls for 2nd & 3rd floors
CANTILEVER OPTION: CONCRETE WALLS
advantages:
•clean connections
•built-in anchorages
disadvantages:
•untested behavior
•specialized construction
•unusual construction
methods
member sizes: 6x 2.5-ftx2-ft
load/strand: 147-kips
•tensioned at base
•anchored in
counterfort
CANTILEVER OPTION: POST-TENSION STRANDS
system description:
•gravity bearing wall with counterfort stifferners
•counterforts act as anchors for PHMRF/PT strands
•2-ft thick counterforts
•22-ft tall wall
•2-ft thick base
advantages:
•utilize weight of soil
•sections may be precast
disadvantages
•long construction time
•increased excavation time and effort
RETAINING WALL OPTION: COUNTERFORT
system description:
•grouted past shear plane
•No. 8 rebar anchors
•high strength grout
•nailed 10-feet o.c.
RETAINING WALL OPTION: SOIL NAILS
advantages:
•brings large loads directly to bedrock
•competent in case of beach erosion
disadvantage:
•obtrusive construction
FOUNDATION SOLUTION: SHEARWALL PILES
•option 1
•pile foundation
•concrete wall for auditorium
•concrete wall for cantilever floor
•option 2
•pile foundation
•steel bracing system for auditorium
•steel cable stay for cantilever floor
CONSTRUCTION OPTIONS
•concrete
wall
vs.vs.
steel
bracingwall
system
•steel cable
stay
concrete
CONSTRUCTIONS ISSUES
temporary
partition
mat’ls
laydown
building
in use
building
under
const.
mobil
e
crane
job trailers
palm
tree
SITE LAYOUT
temporary
easement
main
road
critical phase for scheme 2
CONSTRUCTIONS ISSUES
$178.3/SF
total cost
COST COMPARISON
$176.3/SF
structure cost
excavatio
n start:
10/26/15
excavatio
n start:
10/26/15
SCHEDULE COMPARISON
completion :
oct 14, 2016
structure
finish:
06/02/16
completion :
sep 23,
2016
structure
finish:
05/23/16
A
FIRST CONCEPTS
/ PLAN / 3D
RENDER
$ / STRUCT.
CONCERNS
REFINE PLANS /
CONSIDER ALT.
FACULTY
ARRANG.
E
CANTILEVER
IDEAS
C
EXCAVATION
STUDY
MENTOR
MEETING
FOUNDATIONS
PILE DRIVING $
AUDITORIUM
STRUCTURE
STEEL
BRACING VS.
CONCRETE
SCHEME 2
4.5M
4.45M
4.5
4.45
4.4M
4.39M
4.4
4.35
4.28M
4.28M
4.3
4.25
4.2
4.15
Redesign
option 1
Redesign
option 2
Scheme1
option 1
Scheme1o
ption 2
scheme2o
ption 1
OVERALL COST COMPARISON
scheme2op
tion 2
REDESIGN
- CONS
+PROS
•supports/strengthens
existing architecture
•both 'sign' and function
•small impact to original
schedule
•circulation problems with
cafeteria placement
•tricky connection details
•no LFRS redundancy
•Large surcharge loads
on gymnasium
•Cost increase due to
excavation & water table
DECISION MATRIX AEC 1
SCHEME 1
+PROS
-CONS
•strong conceptual footing
•deeper understanding
•tight programming in interior
•issues developing LFRS
•most interesting space/light
•symmetric
•separate LFRS
•foundation issues
•shaped concrete elements
•Protection for glass sphere
•time savings through
parallel construction
DECISION MATRIX AEC 1
SCHEME 2
+PROS
•expression of circulation
•interesting use of
topography
•innovative LFRS
+CONS
•structural budget dominates
•Large cantilever
•Need soil retainment
•Need suitable foundation
•cantilever floor construction
•Large excavation depth
DECISION MATRIX AEC 1
FIRST SCHEME –
FOURTH ITERATION
A
•most available space for design
development
•symmetric
E
C
•regular column locations
•2 unique LRFS systems
•reduction of cantilever
•ease of construction
•no tower crane conflicts
•initial consideration of all trades
STRENGTHS
•level of camaraderie
•task sharing
•less owner contact
ISSUES
•work in boxes
•cyclic action levels
SUSTAINING THE MOMENTUM…
QUESTION SESSION