The Use of EPS Geofoam Lightweight Fill in Hollywood, FL The Use of EPS Geofoam Lightweight Fill in Hollywood, FL
The Use of EPS Geofoam Lightweight Fill in Hollywood, FL The Use of EPS Geofoam Lightweight Fill in Hollywood, FL
The Use of EPS Geofoam Lightweight Fill in Hollywood, FL The Use of EPS Geofoam Lightweight Fill in Hollywood, FL
L. Zhou
Langan Engineering, Miami Lakes, Florida
C. M. Gonzalez
Langan Engineering, Miami Lakes, Florida
Recommended Citation
Meyer, M. E.; Zhou, L.; and Gonzalez, C. M., "The Use of EPS Geofoam Lightweight Fill in Hollywood, Fl"
(2004). International Conference on Case Histories in Geotechnical Engineering. 12.
https://scholarsmine.mst.edu/icchge/5icchge/session08/12
This Article - Conference proceedings is brought to you for free and open access by Scholars' Mine. It has been
accepted for inclusion in International Conference on Case Histories in Geotechnical Engineering by an authorized
administrator of Scholars' Mine. This work is protected by U. S. Copyright Law. Unauthorized use including
reproduction for redistribution requires the permission of the copyright holder. For more information, please
contact scholarsmine@mst.edu.
THE USE OF EPS GEOFOAM LIGHTWEIGHT FILL IN HOLLYWOOD, FL
Meyer, M.E. Zhou, L. Gonzalez, C.M.
Assistant Project Manager Staff Engineer Senior Associate
Langan Engineering Langan Engineering Langan Engineering
Miami Lakes, FL Miami Lakes, FL Miami Lakes, FL
M. ASCE A.M. ASCE M. ASCE
ABSTRACT:
Expanded Polystyrene (EPS) Geofoam lightweight fill permitted elevation of a loading dock and access roadway to facilitate
offloading of banquet/convention center and hotel supplies, products, etc. directly into the second floor of a development underlain
with highly compressible soils, in Hollywood, Florida. Similar roadways had been previously constructed using conventional filling
techniques and have resulted in continual maintenance problems and grade separation between pile supported structures and roadways
supported on filled ground. The South Florida barrier island geology and interior mangrove swamp areas, which are reclaimed land
formed through the use of dredging and hydraulic filling operations in the early 1960’s, require specialized site preparation techniques.
Typically, preloading, or surcharging, where feasible, is utilized to pre-compress the underlying compressible organic silts and peat
deposits, and often structural relieving platforms/hollow filled structural ramps are constructed to prevent continual maintenance of
critical on-grade supported appurtenances. In this instance, EPS Geofoam lightweight fill was ideally suited to accomplish the
Developer’s and Contractor’s objectives with their fast-track schedule and site constraints.
This paper provides a brief description of the typical South Florida geology, compressibility characteristics of the underlying soft
compressible organic deposits, and our settlement predictions, which showed the need for preloading, structural support or use of one
of the first applications of lightweight fill in South Florida. An in-depth settlement monitoring and instrumentation program was
conducted to confirm the expected behavior of the lightweight fill and the underlying subsurface behavior. Induced stresses through
the overlying pavement and fill material are provided and the general construction procedures utilized are summarized.
INTRODUCTION
Within the largest hotel development constructed in South
Florida, one of the first applications of EPS lightweight fill
was successfully implemented for the support of an elevated
roadway. Approximately 1,150 cubic meters (1,500 cubic
yards) of Type II EPS lightweight fill was placed to raise
grades up to 1.7 m (5 ½ ft) within an area of compressible
ground conditions and documented on-going settlement
related problems. The following sections provide a
discussion of the pertinent design and construction related SITE LOCATION
issues. (SOUTH FLORIDA)
The site is located along the beach within the city limits of
Hollywood, Florida. The project development is located both
on the East (Ocean Side) and West sides (Intracoastal Side)
of South Ocean Drive, with the subject site being located at
the southeast end of the general development. The
approximate site location is shown below in Figure 1.
FIGURE 1- SITE LOCATION PLAN
Paper No. 8.23 1
SOUTH FLORIDA GEOLOGY and long term settlements associated with continual
The South Florida geologic formations consist of near secondary compression were a concern with the underlying
surface oceanfront/beachfront fine to medium grained sands compressible organic silt and peat deposits. Methods of
of the Pamlico Formation and underlying organic silts and minimizing differential post-construction settlements
peats, which are swamp and tidal bay deposits. Both of these between the pile supported Banquet Facility structure and the
formations were deposited relatively recently in geologic adjacent roadway were desired. Even further complicating
terms as the sea level rose well above its current elevation placement of earth fill was the presence of settlement
during the post-glacial epoch. Beneath these deposits are sensitive fiberglass encased chilled water lines, hot water
sedimentary rock deposits of the Miami and Fort Thompson lines, and electric lines encased in concrete (ductbanks),
Formation. The Miami Limestone is a white to tan sandy which had been installed within the area of the planned
oolitic limestone and is typically more consistent than the roadway. The figure below shows a cross-section of the
underlying older Fort Thompson Formation. The Fort originally planned construction.
Thompson formation is composed of sands, cemented sands,
cemented sands and shells, limestones, and sandstones. This
formation typically contains cemented zones which are
significantly harder than the Miami Formation, and contains
zones which are partially or completely uncemented in nature
(Hoffmeister, 1974).
PROJECT DESCRIPTION
To provide vehicular access into the second floor of the FIGURE 2- EXISTING CONDITIONS & PROPOSED
banquet facility and allow offloading and loading of SOIL EMBANKMENT (CROSS-SECTION)
products, supplies, etc., an elevated loading dock and access
roadway was required. The ground floor of the banquet SUBSURFACE CONDITIONS
facility would serve as ground floor and valet parking. An Site specific subsurface conditions were determined through
approximate 107 m by 12 m (350 ft by 40 ft) access roadway the use of mud-rotary drilling techniques and casing as a
and loading dock were planned to be constructed. This stablizing technique where necessary. Standard Penetration
roadway was to be located immediately adjacent to the Tests were typically performed continuously for the upper
project’s recently completed 8-story Banquet Facility approximately 3 m (10 ft) and at 1.5 m (5 ft) intervals
supported on augercast piles, and an existing neighboring thereafter. The standard penetration tests were performed
one-level garage supported on driven precast concrete piles using a 140 lb safety hammer falling 0.75 m (30 inches) in
attached to a 15-story condominium. Research of available accordance with ASTM procedures.
plans at the local building department indicated that the
adjacent neighboring structure was supported on a system of The subsurface conditions generally consist of 10 ft of fine to
grade beams and pile caps; however, the ground floor level medium grained sands underlain by 1.2 m (4 ft) to 2.1 m (7
slab was supported on grade at el + 1.5 m (el +5 ft). Visual ft) of organic silts and peats. The sands are typically loose to
inspection of this slab showed it to be in relatively good medium dense based on their range in SPT N-values from 8
condition. It was determined that repair of the ground floor bl/0.3 m to 20 bl/0.3 m and average of 15 bl/0.3 m. The
slab of the neighboring structure was unacceptable and a organic silts and peats are typically soft to very soft based on
method must be designed so as not to adversely effect its slab their range in SPT N-values from 2 bl/0.3 m to 4 bl/0.3 m and
on grade. average of 3 bl/0.3 m.
The proposed access roadway and dock required filling of the Laboratory natural water content determination tests were
site up to 1.7 m (5.5 ft) above the previous existing site performed on the samples retrieved from the split-spoon
grades. Both immediate (primary consolidation) settlements sampler. A large variation of in-situ water content was
70
60
Range of Laboratory
40
0
10 100 1000
Natural Water Content (%)
10
SUBSURFACE CONDITIONS
South Florida Peats (+/-15%)
detrimental settlements have been observed over extended FIGURE 5- COMPRESSIBLITY PARAMETERS OF
periods of time as a result of continual settlement associated SOUTH FLORIDA ORGANIC SOILS
with these organic soils, which is attributed to secondary
compression. ROADWAY AND LOADING DOCK SUPPORT
ALTERNATIVES & SOLUTIONS
Extensive information regarding the compressibility The key geotechnical issues identified relative to raising of
characteristics of the South Florida organic silts and peats has grades up to 1.7 m (5.5 ft) above previous existing grades
been obtained over the past 30 years of research by the were as follows:
authors’ firm. In addition, an extensive preloading program • Post-Construction settlement of roadway embankment
was performed for the northernmost portion of the subject relative to pile supported Banquet Facility (i.e. abrupt
project, an adjacent golf course and country club differential settlements at transitions from on-grade to
development and adjacent 60 ½ Hectare (150 acres) site of pile support);
single family two-story and townhouse structures designed
200
TYPE VIII EPS
DENSITY- 20 kg/m 3
150
100
50 TYPE I EPS
DENSITY- 15 kg/m 3
0
0 5 10 15 20
Strain (%)
FIGURE 9- EPS GEOFOAM LIGHTWEIGHT FILL
FIGURE 7- LABORATORY UNIAXIAL COMPRES- EMBANKMENT DETAIL (CROSS-SECTION)
SION TEST ON EPS GEOFOAM (BASF, 1995)
Due to limited site access, the presence of an existing
To allow the designer to specify the appropriate density of building on the south and the newly constructed banquet
geofoam material, relationships have been developed for the facility on the north, the geofoam construction occurred in
initial tangent modulus (elastic modulus) based on the two phases with the southern phase being constructed first.
various geofoam densities. Figure 8 below shows this Prior to placement of the geofoam blocks, the existing grade
relationship graphically. was cut to 0.8 m (2.5 ft) below the previous site grade to
provide minimal increase in stress within the underlying
compressible organic stratum. The subgrade was then
Initial Tangent Modulus of EPS Geofoam
proofrolled with a large vibratory roller and a layer of fine to
35 medium grained sand was placed and compacted to provide a
level surface for placement of the EPS geofoam blocks. The
30 blocks were then placed in such a manner that no
RELATIONSHIP OF Eti joints/seams were aligned, and the uppermost blocks were
WITH EPS DENSITY
EPS Geofoam Density (kg/m3)
25 (Horvath, 1995) positioned with the long dimension of the block being
oriented perpendicular to the direction of traffic flow. The
20
thickness of the EPS block embankment averaged 1.2 m (4
MANUFACTURER A
ft). After completion of placement of the EPS Geofoam
embankment, a geomembrane and a concrete protection layer
15
were constructed to allow subsequent filling operations to be
safely performed and to provide protection from future
10
contact with petroleum products over the life of the roadway.
Utilities were either routed on top of the geofoam protection
5 MANUFACTURER B
layer or beneath the bottom block of geofoam. After curing
of the concrete protection layer, filling commenced to the
0 planned pavement subgrade elevation using imported clean
0 2 4 6 8 10 12
crushed limestone having a maximum dry density of 20.5
Initial Tangent Modulus (MPa)
KN/m3 (130 pounds per cubic foot), an optimum moisture
FIGURE 8- INITIAL TANGENT MODULUS content of 8%, and a Limerock Bearing Ratio in excess of
RELATIONSHIP FOR VARIOUS EPS GEOFOAMS 100 (i.e., Florida Test Method FM 5-515). The fill was
placed in 0.3 m thick (1-ft-thick) loose lifts using light
1. The current design procedures regarding stress Lambe and Whitman, (1969) Soil Mechanics, John Wiley &
distribution of traffic loads based on conventional Sons.
theories of elasticity or design manual
recommendations (i.e. 2V:1H distribution) are Yu, K.P. (1993). Site Stabilization in Hurricane Region,
conservative based on the results of the stress Proceedings, Third International Conference on Case
monitoring program. Histories in Geotechnical Engineering, St.Louis, Missouri,
Paper No. 7.14, pp. 995-1006.
2. EPS geofoam provides a technically feasible
alternative for support of roadways in compressible
ground conditions.