CE 241 Advanced Concrete Technology - Civil and Environmental ...

CE 241
Advanced Concrete
Technology

CE 241
Advanced Concrete Technology
Instructor: Paulo J.M. Monteiro
725 Davis Hall
Office hours: Monday 1-2 am, Tu Th 10-11 pm at 725 Davis Hall
Email: monteiro@ce.berkeley.edu
Grade: 10% HW + 20 % paper + 5% Presentation + 20% Midterm + 45% Final

Why a concrete technology
course?
Paradigm change: More money is
being spent in repairing structures
than in new structures.
t
50% of 500,000 bridges in distress
~ 200 billion to repair
204 dams with AAR

Need for materials
New materials that you should
specify: green concrete, type of
cement, recycled aggregates, high-
strength concrete, low-heat
generation concrete

New criteria
Low-shrinkage
Crack Free
Maximum temperature rise
Architectural concrete
Environmental Impact

TWO MAJOR CHALLENGES
Challenge I: Environmental Impact
World demand/year
•11.55 billion ton of concrete
•1.5 billion ton of cement
•1 billion ton of water
•99 billion ton of aggregate

Consequences (1)
1.5 billion ton of cement Problem!
Generates 1.5 billion
ton of CO 2
Responsible for 5-7%
CO 2 production in
the world

Business as usual is
not an option!

Consequences (2)
1 billion ton of water
110,000 times the amount of water in
the SF Bay

Consequences (3)
9 billion ton/y of aggregate
Depletion of
natural
resources

Challenges
Challenge II: Long-term durability
Civil Infrastructure quickly
deteriorating
March 17,
2008,
I-95 in
Philadelphia

Major deterioration
Corrosion of reinforced concrete
Sulfate attack
Alkali silica reaction
Hot and cold weather

Consequences
Of the 597,340 bridges in this
country, 73,784, 784 or about
12.4 percent, are structurally
deficient.

Examples
Itaipu Dam
Nervi Structures
Petronas Tower

Itaipu Dam

To reduce the amount
of concrete in the dam,
the center of the block
is hollow

The spillway, with a
length of 483 m, was
designed for a
maximum discharge
capacity of 62,220
m3/s.

Rome Sports Palace in
Rome
Nervi was a pioneer of “ferrocemento”
or reinforced
mortar, where thin metallic
meshes are embedded in a
mortar to form structural
elements with high ductility
and crack-resistance

High Strength Concrete

Jan 1994
(photograph courtesy from Leornardo Garzon)

April 1994
(photograph courtesy from Leornardo Garzon)

August 1994
(photograph courtesy from Leornardo Garzon)

September 1994

October 1994

November 1994
(photograph courtesy from Leornardo Garzon)

December 1994
(photograph courtesy from Leornardo Garzon)

February
1995
(photograph courtesy from Leornardo Garzon)

May
1995
(photograph courtesy from Leornardo Garzon)

September
1995
(photograph courtesy from Leornardo Garzon)

February
1996
(photograph courtesy from Leornardo Garzon)

Introduction
A semester in one hour -- relax and
enjoy…
Pre-requisites: none (the course will
be self-contained)
Textbook: Mehta & Monteiro (hid (third
edition)

Structure and properties
of hydrated cement paste
Objectives:
Learn how the
microstructure controls the
properties of concrete.
Identify the main crystals
present in concrete

Transition zone
in concrete
Objectives:
Reinforce the concept that
concrete is not a
homogeneous material.
Show that the zone
between the aggregate and
the cement paste is the
“weak link” of concrete
affecting many of its
properties.

Factors influencing the
strength
Objectives:
Review the main parameters controlling the strength
development of concrete structures.

Concrete strength under
various stress states

Elastic behavior

Creep and drying
shrinkage
Objectives:
To study the mechanisms
of creep, modeling, and
structural t consequences.
Show that creep and
shrinkage have the same
mechanism.

Thermal stresses
Objectives:
Analysis and control of thermal stresses due to the
hydration of cement.
Applications to dams, off-shore platforms, cathedrals, etc.

Permeability and
durability

Durability to frost action and fire
Objectives:
Describe the mechanism of deterioration caused by ice formation
in concrete.

Deterioration of concrete
by chemical attacks
Objectives:
Describe the damage mechanisms
caused by sulfate attack and alkali-
silica reaction.

Deterioration from electrochemical
phenomena

Concrete structures in
marine environment

Concrete aggregates
Objectives:
Discuss the importance of
aggregates in concrete technology.

Hydraulic cements

Chemical admixtures
Objectives:
Discuss the importance of chemical admixtures for the
manufacture of advanced concrete

Mineral admixtures
Objectives:
Discuss the advantages of using
mineral admixtures both to
improve the properties of concrete
and to reduce the pollution in the
world.

Lightweight and
heavyweight ht concrete

High-strength and high-
performance concrete
Objectives:
To introduce mix proportions to
obtain high-strength concrete and
to discuss construction ti methods
using HSC
Green Concrete

Shrinkage-compensating
concrete

Fiber-reinforced reinforced concrete

Mass concrete
Objectives:
Techniques to minimize the thermal
stresses in concrete.

Polymers in concrete
Objectives:
To present new research using
polymers in concrete to improve
various properties.

Fracture Mechanics

Non-destructive Methods