Deep Foundations for Transportation Facilities: A Historic ......Deep Foundations for Transportation...
Transcript of Deep Foundations for Transportation Facilities: A Historic ......Deep Foundations for Transportation...
October 12, 2016
DEEP FOUNDATIONS FOR TRANSPORTATION FACILITIES: A HISTORIC PERSPECTIVE
John G. Delphia
TxDOT Bridge Division – Geotechnical Branch Manager
October 12, 2016
TxDOT Foundation Use - Historical Perspective
2
-- Spread footing foundations were used occasionally into the 1970’s to support
bridges in competent soil or rock, but the increasing economy of drilled shafts
resulted in an end to the use of spread footings.
-- Driven piling have been used effectively in softer soils, as they displace the soil
and rely on skin friction.
-- TxDOT has used drilled shafts to found bridges since the late 1940’s. Drilled
shafts can be used in a wide variety of soil/rock conditions. TxDOT is
generally considered to be the largest user of drilled shafts in the United
States.
October 12, 2016
Spread Footing
3
October 12, 2016
TxDOT Deep Foundations
4
DEEP FOUNDATIONS
PILING DRILLED SHAFTS
October 12, 2016
TxDOT Piling – Historical Perspective
5
1925 – Concrete Structures -
Substructure Design - “For
streams where erosion is
possible, piling should
preferably be used (if possible
to drive) as a protection against
scour, even though the safe
bearing resistance of the
natural soil is sufficient to
support the substructure
without piling.”
1950 – Timber
Piling, Precast
Concrete Piling, and
Steel H Piling were
included in the
TxDOT
Specifications Book.
1962– Steel Piling
(Steel H and Sheet
Piling) replaced
Steel H Piling. Metal
Shell Piling was
included in the
TxDOT
Specifications Book.
1993– Metal Shell
Piling was removed
from the TxDOT
Specifications Book.
October 12, 2016 6
http://www.vulcanhammer.info/on/differential.php
Pile Driving
~ 1940’s
Pile Driving
~ 1950’s
http://www.vulcanhammer.info/on/photos.php
Pile Driving
~ 1960’s
http://www.vulcanhammer.info/products/leaders.php
October 12, 2016
Piling
7
Diesel Hammer
Hydraulic Hammer
Vibratory
Hammer
October 12, 2016
Piling
8
Timber Piling
Steel Pipe
Piling
Steel H PilingConcrete
Piling
October 12, 2016
TxDOT Drilled Shafts – Historical Perspective
9
(From: http://www.ahbeck.com/)
1962 –
Introduction of
slurry into the
TxDOT
Specifications.
1972 –Human
/visual inspection
of the bottom of
the hole is still
required. Belled
Drilled Shafts
being used less.
1950 – Drilled
Shafts included
in the TxDOT
Specifications
and human
inspection of bell
shaped footing.
1932 – Several companies in
Texas first started using
drilled shafts for private jobs.
Pioneering work on drilled shafts was funded by TxDOT beginning in
1968. Dr. Lymon Reese and Dr. Mike O’Neill performed the bulk of
this research at the University of Texas and later the University of
Houston. This research was included in the FHWA Drilled Shaft
Manual.
1993 - TxDOT
Specification was
updated to include
slurry requirements,
underwater placement ,
and no human
examination of the
bottom of the hole.
TxDOT first used drilled shafts to found bridges in the late
1940’s.
October 12, 2016
Drilled Shafts
10
Drilled Shaft Equipment
~ 1950’s
October 12, 2016
Belled Drilled Shafts
11
Reamer for Belled Shaped Drilled Shafts
~ 1950’s
Soil
Rock
October 12, 2016
Drilled Shafts
12
Drilled Shaft Equipment
~ 2005
October 12, 2016
TxDOT Deep Foundations
13
DEEP FOUNDATION DESIGN
TEXAS CONE
PENETROMETER
TESTING
DESIGN
CORRELATION
CHARTS
October 12, 2016
Texas Cone Penetrometer History
14
Development of the Texas
Cone Penetrometer (TCP)
Test
1949 – First
use of the TCP
test.1956 – TCP
correlation charts first
published. Drilled
shafts designed for
point bearing. Skin
friction for Piles.
1972– TCP
correlation charts
were updated.
Drilled shafts
designed for skin
friction and point
bearing.
1982 & 2000– TCP
correlation charts
were updated.
October 12, 2016
Texas Cone Penetrometer
15
October 12, 2016
Texas Cone Penetrometer Design Curves
16
October 12, 2016
TxDOT Design Method History
17
History of TxDOT Design Method
1949 – 1971
- spread footing designed on bearing
- piling designed on skin friction
- drilled shaft designed on point bearing
1972 – Present
- spread footing on rock designed on bearing
- piling designed on skin friction
- drilled shafts designed on combination of
skin friction and point bearing
October 12, 2016
Drilled Shaft Design
18
Soil
Rock
Rock Bearing
Soil
Rock
Soil
Skin
Friction
Rock Skin
Friction
Rock
Bearing
October 12, 2016
Recent Advancements in Deep Foundations
19
DRILLED SHAFTS
• Large Diameter Mono Drilled Shaft
FOUNDATION TESTING
• Thermal Integrity Profiler (TIP) Testing of
Drilled Shafts
• Statnamic Testing
• High Strain Dynamic Testing
October 12, 2016
12 Foot Diameter Drilled Shaft
20
Due to a variety of reasons large diameter mono
drilled shafts are being used on TxDOT bridges.
October 12, 2016
Thermal Integrity Profiler (TIP) Testing
21
Thermal Integrity Profiler (TIP):
- uses the temperature generated by curing cement (hydration energy) to assess the
quality of a drilled shaft.
- evaluates the entire cross-section and the entire length of the foundation. Results
are available shortly after shaft installation is concluded.
- reveals necks or inclusions, bulges, variations in concrete cover, shape of the
shaft and cage alignment.
October 12, 2016
Statnamic Testing
22
The Statnamic load test is a type of
test for assessing the load carrying
capacity of deep foundations, which
is faster than a traditional load test.
October 12, 2016
High Strain Dynamic Testing
23
High strain dynamic testing is a method
of testing deep foundations to:
• obtain information about
capacity
• obtain information about
integrity
• monitor their installation.
It is a standard test method in ASTM:
D4945-08 - Standard Test Method for
High-Strain Dynamic Testing of Piles.
Pile Driving Analyzer (PDA)
October 12, 2016
Deep Foundations for Transportation Facilities: A Historic Perspective
24
TxDOT:
• utilizes deep foundations to support transportation facilities,
namely bridges.
• has a long and successful history with deep foundations for use
on bridges.
• has done a lot of leading edge research on drilled shafts, which
has advanced the use and knowledge of them.
Let’s see what advancements will be made in the future.
October 12, 2016
Deep Foundations for Transportation Facilities: A Historic Perspective
25
QUESTIONS?
October 12, 2016
Deep Foundations for Transportation Facilities: A Historic Perspective
26
Copyright 2016 • Texas Department of Transportation • All Rights Reserved
Entities or individuals that copy and present state agency information must
identify the source of the content, including the date the content was copied.
Entities or individuals that copy and present state agency information on their
websites must accompany that information with a statement that neither the
entity or individual nor the information, as it is presented on its website, is
endorsed by the State of Texas or any state agency. To protect the intellectual
property of state agencies, copied information must reflect the copyright,
trademark, service mark, or other intellectual property rights of the state agency
whose protected information is being used by the entity or individual. Entities or
individuals may not copy, reproduce, distribute, publish, or transmit, in any way
this content for commercial purposes. This presentation is distributed without
profit and is being made available solely for educational purposes. The use of any
copyrighted material included in this presentation is intended to be a “fair use” of
such material as provided for in Title 17 U.S.C. Section 107 of the US Copyright
Law.