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City of West University Pl
ace
A Neighborhood City
® Recycled Paper
Workshop on Foundations
Building & Standards Commission
Public Works Building, Located in the Public Works Conference Room,
3826 Amherst Street
Meeting Minutes
April 201h, 2004
MEMBERS PRESENT: Bryant Slimp, John Ayres, and Kevin McMahon.
MEMBERS ABSENT: Brian Hoogendam, David Flame, Dr. Peter Benjamin, J. Denis Powers,
Darryl Friday, Brian Hoogendam and Muddy McDaniel.
COUNCIL LIASION: None.
STAFF PRESENT: Annette Arriaga, Dennis Mack and Jim Dougherty.
GUESTS: David Eastwood P.E., Michael A. Skoller P.E., and Robert Riquelmy
and Les Albin.
[Call to Order.] With a quorum, present Bryant Slimp called the meeting to order at 5:40p.m.
1. Foundations. Bryant Slimp introduced Mr. David A. Eastwood P.E., President of Geotech
Engineering and Testing and Mr. Michael Skoller P.E., President of National Structural
Engineering, Inc. Mr. Eastwood provided the workshop members with a slid presentation and
discussed soil and materials for the design and construction of residential structures.
The outline of Mr. Eastwood's presentation was:
❑ Study of Area Faulting and Subsidence
❑ City Requirements for Geotechnical Exploration
❑ Field Studies
1. Site Conditions
2. Drilling Equipment
3. Sampling Methods
4. Groundwater Sampling
❑ Laboratory Testing
❑ Analysis of Data
❑ Expansive Soils
❑ Foundation Types Design and Construction
1. Drilled Footings Inspection
2. Slab Inspection
3. Concrete Testing
❑ Foundations Failures and Repair Techniques
❑ Soil Stabilization
1. Lime Stabilization
2. Cement Stabilization
3800 University Boulevard 0 West University Place, Texas 77005-2899 0 7139668.4441 • www.westu.org
Building and Standards Commission Workshop Meeting Minutes
April 20th, 2004
Page 2of 3
Mr. Eastwood discussed different types of land subsidence and hydraulic cross sections. He showed
maps of the Houston Addicts showing that it does drop about one half of an inch a year and that the
drop is largely due to groundwater withdrawal. The slide presentation showed the Houston area
fault map and the Gulf Coast Faults. He also showed Arial photos of the Houston and Bellaire area
faults. The presentation also explained portable drilling rigs, how the machines take soil samples
and explained some of the field test methods such as the standard penetration test that measures the
number of blow counts to move the test devise.
The slides demonstrated the treatment of soils samples and the different laboratory tests of those soil
samples for parameters such as moisture content, plastic content, liquid limits and proctor tests.
Some soil tests show the density and moisture content, plasticity index and optimum moisture
levels. The slide presentation presented an engineering analysis and a map of different types of
surface geology of the Houston. Mr. Eastwood presented information about common area clays and
sands. He presented information on:
Swell Potentials
1. Clay and Sandy Clay.
2. Salty Sand or Clay Sand.
3. Clay and Sand Clay.
Plasticity Index (Pl):
1. 20 Low.
2. 20-30 Moderate.
3. 30 - 40 High.
4. 40 Very High.
Mr. Eastwood discussed the foundation risks for each foundation type:
❑ Structural Slab with Piers
❑ Slab on Fill Supported on Piers
❑ Floating (Stiffened) Slab Supported on Piers
❑ Floating Super Slab (Conventionally Reinforced on Post-Tensioned Slab)
❑ Floating Slab Foundation (Conventionally Reinforced on Post-Tensioned Slab)
Piers & Beams Details
❑ Exterior beams
❑ Interior beams
Mr. Eastwood also discussed the design conditions and uplift as well as the floor slab treatments
under foundations.
Bryant Slimp stated that he would like five bullets from David Eastwood for the foundation
ordinance draft. Michael Skoller mentioned that he would like some design methods incorporated
into the code. Dennis Mack stated much of the criteria is in the International Residential Code, but
contractors are not following it and he does not have any say over soils of foundation professionals.
Jim Dougherty stated that he would not disagree about hiring a person/engineer that checks the
structural plans, however, an engineer might not like the fact that another P.E. is checking their
work. Jim Dougherty stated he had no objections to that idea. John Ayres stated that would be a
good type of mechanism.
Les Albin added that in his opinion that there are two major over sites and failures:
1. Engineers that rubber stamp work.
2. Engineers that miss something on the plans.
Jim Dougherty stated that this type of system would work. If you do not do it by "the book" then you
would have to pay. There are other measures that the City can take such as reporting bad
Building and Standards Commission Workshop Meeting Minutes
April 20th, 2004
Page 3of 3
engineering to the State Board. Certifying that all of the steps have been followed, and otherwise
falsifying documents could be classified as a felony or a misdemeanor and would serve as a an
incentive to do well.
Bryant Slimp asked, "How we could get a good soils report as part of our permit system
requirements?" Jim Dougherty stated that we could require a Geotechnical Investigation. Mr. Skoller
stated that Geotechnical Engineering would tell the depth of the piers.
❑ He also added that there are three risk categories: High, Moderate and Low risk
Mr. Skoller continued to add that all of the foundation designs must limit potential movement to a
maximum of one inch. A potential vertical rise (PVR) standard or a performance standard would be
an excellent method to address this issue.
He recommends the use and reference to the ASCE guideline, which was in our reference material
labeled Final Draft Document 4.6.5.2.1 under section 4.3.3 & 4.3.3.1.
Jim Dougherty added that the City could have required a highly specific soils report along with the
PVR calculations that the foundation design must achieve. The builder would have to provide a
Geotechnical report with the foundation permit application. Jim Dougherty asked if BSC wants to
come up with a performance type of report? BSC members agreed.
Bryant Slimp asked if Jim Dougherty and Dennis Mack could come with a list of specifications and
requirements.
[Adjournment.] Meeting adjourned at 7:45 p.m.
PASSED THIS 3r- DAY OF (AAfU,
, 2004.
Bryant limp, Chairma i
ATTEST: V
Ms. Annette R. Arriaga Development Serv*eretary