Post on 08-Jan-2022
Unique Concrete Technologies
By: Ron Vaughn, Northeast Solite Corporation
SOLITE®1
LEARNING OBJECTIVES
1 SCC (Self-Consolidating Concrete)
2 Flowable Fill (Controlled Low-Strength Material)
3 Cellular Concrete (Low Density Concrete)
4 Lightweight Concrete
5 Shotcrete
6 Pervious Concrete
7 ICF’s (Insulated Concrete Forms)
8 Tilt-up Concrete Structures
Attendees will learn about the eight (8)
unique concrete technologies that follow:
Topic Index:
1 SCC (Self-Consolidating Concrete)
2 Flowable Fill (Controlled Low-Strength Material)
3 Cellular Concrete (Low Density Concrete)
4 Lightweight Concrete
5 Shotcrete
6 Pervious Concrete
7 ICF’s (Insulated Concrete Forms)
8 Tilt-up Concrete Structures
1- SCC (Self-Consolidating Concrete)
• Highly flowable, yet stable concrete
• Fills formwork without the need for manual placement
• Consolidates around reinforcing without added vibration
RHEOLOGY:
The science of the deformation and flow
of materials.
SSelf-Consolidating Concrete T20
1. When the SCC flow reaches 20 inches
in diameter, indicated by a circle
marked on the slump flow board, the
stopwatch is stopped.
2. The time is reported to the nearest 0.1
seconds.
3. Typical values are 2-5 seconds with
higher values indicating greater
stability.
4. The T20 is determined during the
slump flow measurement. The
stopwatch is started when as the
Abram’s cone is first lifted.
20”
Slump Flow with T-20
SCC Test Methods – Slump Flow
1. A traditional Abram’s Cone (normal or inverted) is filled in one lift (no rodding or other
consolidation) with SCC, taking care to be sure the sample is well mixed and not
segregated in the sampling process.
2. The cone is then raised over 5 seconds to a height of 12 inches, allowing the fluid
concrete to flow onto the slump flow board.
3. The slump flow is the diameter of the resulting concrete “patty” obtained from the
average of measuring the greatest diameter and diameter perpendicular to this direction
4. The result is reported to the nearest half inch.
Guess
which
one was
made
using
SCC!
2- Flowable Fill
(Controlled Low Strength
Material)
Flowable fill may have strengths up to 1200 psi
Catagories:
Excavatable or Removable is up to 300 psi
Non-excavatable or non-removeabable is 300 psi to 1200 psi
Composition of Flowable FillFill
• Cementitious with: (Portland Cement, Fly
Ash and/or Slag)
• Sand
• Water
• Air (Usually 10 to 30%
Property Comparisons
Property CLSM Typical Concrete
Cast Density 75-115 pcf 150 pcf
28-day
compressive
strength
100 psi or less 3000 psi
Slump Flowable 3” - 5”
Voids Before Placement
Bulkheading required to contain flow
Placement Procedure
Placement Procedure
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3 - Cellular Concrete
(Low-Strength Fill)
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What is Cellular Concrete?
ACI Definition: Low-
Density Cellular
Concrete is a material
made with hydraulic
cement, water and
preformed-foam.
Recipes may include
fly ash, and admixture.
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Cellular Concrete
(Low-Strength Fill)
Benefits Benefits
A. Generally low in cost load reduction
B. Placed by Pump or Gravity
C. Lightweight
D. Durable and Noncorrosive
E. Permanent and Stable
F. High Slump (Self Leveling)
G. Provides100% Compaction in Fill Spaces
H. No Shrinkage
I. Range of Densities & Strengths
J. Freeze-Thaw Resistant
K. Insulating
L. Low Absorption & Permeability
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Cellular Concrete
Road Section
Structural Concrete Options
Classification and Density
• Normal Weight 150 PCF
• Normal Weight w/IC 144 PCF
• Modified Density 126 PCF
• Lightweight 113 PCF
• 100% Lightweight 90 PCF
4 - Lightweight Concrete
Rotary Kiln Making Lightweight
Aggregate
Lightweight Aggregate
Lightweight AggregateNormal Aggregates
Preconditioning of the
Lightweight Aggregate
• It is essential that the lightweight aggregate fines has sufficient absorbed moisture
• If it is not pre-wet, its beneficial results are reduced.
External CuringSprinkling, Wet Burlap, Ponding, Fogging
Curing 20mm
Penetration
Full SlabCuring
withLWAS
Internal CuringSaturated Lightweight Aggregate Sand
Lightweight Aggregate
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CURING
External CuringSprinkling, Wet Burlap, Ponding, Fogging
Curing 20mm
Penetration
Full Slab
Curing withLWAS
Internal CuringSaturated Lightweight Aggregate Sand
Lightweight Aggregate
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CURING
Seneca Indian Casino,
Niagara Falls, NY
Paul Brown Stadium
Cincinnati, OH
Projects with Lightweight
Concrete
Key Bridge
over Potomac
between VA
& DC
Brooklyn
Bridge
NYC
Governor Nice Bridge
Dahlgren, VA Rt. 301 across
the Potomac
Point of Rocks Bridge Maryland Rt. 15 across the Potomac
Additional Lightweight Projects
5 - Shotcrete
• The ACI definition of shotcrete follows: mortar or concrete pneumatically projected at high velocity onto a surface; also known as air-blown mortar, and gunned concrete.
• Shotcrete, dry-mix: shotcrete in which most of the mixing water is added at the nozzle.
• Shotcrete, wet-mix: shotcrete in which the ingredients, including water, are mixed before introduction into the delivery hose; accelator, if used, is normally added at the nozzle.
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Shotcrete Process
Materials used in the shotcrete process are generally the same as
those for conventional concrete. Shotcrete projects also call for the
same types of reinforcing as specified for conventional concrete.
30
Some Applications:
Retaining Walls
Slope Protection
Bridge Retrofits
Unreinforced
Masonry
Structural Repairs
Overhead Repairs
Swimming Pools
Ponds
Water Features
Artificial Rocks
Shotcrete
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Shotcrete
ARTIFICAL ROCK – It is sculpted, colored, and stained
shotcrete that is made to simulate the appearance of real
rock. It is also called ”Faux Rock” and it can be used in many
applications.
Pervious concrete is a special type of concrete with high
porosity used for concrete flatwork applications that allows
water from precipitation and other sources to pass directly
through, thereby reducing the runoff from a site and allowing
groundwater recharge. This is also called porous concrete,
permeable concrete, no fines concrete, and porous pavement.
It is used in parking areas, residential streets, pedestrian
walkways, and greenhouses.
6-PERVIOUS PAVEMENT
Cross Section
The proper utilization of pervious concrete is a recognized Best
Management Practice by the US Environmental Protection
Agency(EPA) for providing first flush pollution control and storm
water management. It contributes to Storm Water Control and
Purification through the Use of Higher Strength Pervious Concrete
and Bio-remediation when using Absorbent Lightweight Aggregate
as the base layer. It also reduces the need for separate storm
water retention ponds and allows the use of smaller capacity
storm sewers.
Pervious Concrete
Pervious & Infiltration Systems
View Stormwater as a Resource
•Slow down the flow, allow to
infiltrate
•Manage stormwater on-site
•Reduces pollutant loads to
waterbodies
The Edison Environmental Center
in NJ and the Science Museum
(National Fish & Wildlife) in VA
projects show that infiltration and
pervious are a good combination to
better handle and purify storm
water. Science Museum, VA
Establishment of Infiltration and
Pervious Concrete System
Using Expanded Shale Lightweight
Aggregate Sand (LWAS) to Provide
Higher Flexural and Compressive
Strength to Pervious Concrete
Highway Shoulders and Parking
Areas Through the Improved
Hydration of the Cementitious
Material, and Through the Improved
Bio-remediation of the Porous
Aggregate
Pervious Pavement
w/ESA Base
Infiltration
The use of LWA as the stone
reservoir below the pervious
pavement increases the void
content and water handling
capacities for the storm water in
the system. It provides superior
filtering, reservoir capacity,
nitrogen removal and p-sorption.
Using LWA® decreases the depth
of the layer that is required with
normal weight aggregates. Bio
agents are harbored in the LWA
pores and do not wash out
completely in rain events.
Trench along pavement edge
V-Trench
Stone filled trench
Pervious Concrete with Infiltration
Pervious
Concrete
Placement
6”
Pervious
Slab
Pervious Concrete with Internal Curing
Internal Curing Can Replace 6 mil Poly for Curing
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7-ICF’s (Insulated Concrete Forms)
Insulating concrete forms are hollow blocks or panels made of
expanded polystyrene insulation (EPS) or other insulating foam that
construction crews stack to form the shape of the walls of a building.
The workers then fill the center with reinforced concrete to create the
structure.
ICF construction sandwiches a heavy, high strength concrete between
two layers of a light and highly insulated form. This combination
creates a wall with many desirable properties: air tightness, strength,
sound attenuation, insulation, and mass.
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ICF’s
Insulated Concrete Forms are
revolutionizing modern construction and
rapidly changing the way we build
structures. Cost effective, sustainable
and environmentally friendly, ICF
construction is a superior way to build.
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ICF’s
ICF’s make stronger, quieter,
healthier, and more efficient
buildings. They reduce
construction time and labor
costs., offer cost savings, provide
superior comfort, protect the
environment, and ensures
maximum safety. About 1/6 of the
sound gets through an ICF wall
compared to an ordinary framed
wall. Their superior insulation, air
tightness, and mass can reduce
the operating cost of HVAC by up
to 40%.
8-Tilt-up Concrete Structures
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Tilt-up construction is ready-mixed concrete placed in
horizontal forms at the construction site and then tilted up to
form walls. Panels are cast as near to the final position as
possible. The most convenient casting base is most often the
concrete floor slab of the building. The wall panels are cast on
the base concrete , cured, and then tilted into a vertical
position and moved into place with a crane.
MGM Disney World
Orlando, FL
Tilt-up Warehouse
York, PA
Tilt-up
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Tilt-up construction is most frequently used for one story
commercial buildings such as warehouses, office buildings,
or big box stores. However two, three, or four story are
becoming more common place.
Tilt-up can also be colored, textured, and shaped to meet
almost any architectural demand using techniques such as
form liners, pigments, brick facing, curved surfaces, and
exposed aggregate
Questions
• Expanded Shale Aggregate is manufactured in a _______ _______ .
• Answer:___________
• Structural Concrete make with expanded shale lightweight coarse aggregate and natural sand will have an approximate air dry density of:_____PCF
Answers
• Expanded Shale Aggregate is manufactured in a Rotary Kiln .
• Answer: Rotary Kiln
• Structural Concrete make with expanded shale lightweight coarse aggregate & natural sand will have an approximate air dry density of: 113 PCF
• Answer: 113
Questions
• Tests used with Self-Consolidating Concrete include which of the following:
• A) Slump Flow B) T-20 C) Both
• Answer: ___________
• Preconditioning of the lightweight aggregate with sufficient absorbed moisture is essential?
True______False______
Questions
• Tests used with Self-Consolidating Concrete include which of the following:
• A) Slump Flow B) T-20 C) Both
• Answer: C) Both
• Preconditioning of the lightweight aggregate with sufficient absorbed moisture is essential for Internal Curing?
True___X___False______
Questions