Facing page: The safety of mobile
home construction is a growing problem in the U.S.
Based on shortcomings observed in this study, the following research. is suggested to improve anchoring technology, design and regulation.
Preparation of standard nomenclature to be used to describe
soils and rock for anchoring purposes. This information
is readily available and merely needs to be adopted as an
industry-wide standard and presented in a form usable by
all segments of the industry.
Preparation of a standard method for performing field pull-
out tests. This standard should address such items as type
and size of a load test frame used to apply the pull-out
load; accuracy of load-deflection measurements; minimum
requirements for soils and rock classification including
strength determination by in-situ tests; and details on the
information that the test report should contain.
A field test program considering response of available anchor
types in various soil and rock types to establish a correlation
between pull-out capacity and such field tests as the standard
penetration test, the soil test probe, and others. Particular
attention should be paid to the amount of displacement undergone
by an anchor head, which, it is felt, has largely been ignored
in the past. The field testing should include both static and
dynamic (cyclic) testing with particular emphasis on the dis-
placement occurring under repeated loads, and loading which
is not coaxial with the shaft of the anchor, similar to that
actually experienced by mobile homes anchors. As a result of
this test program information should be available on the
effects of cyclic and sustained loading and saturation of the
supporting soil.
Development of standard performance tests (pull out as well
as proof) by which the adequacy of installed anchors can be
determined.
This report, in draft form was sent out to various individuals for review and comments. The authors gratefully acknowledge the constructive criticism and helpful suggestions from the following individuals.
M. Alexander, Texas Department of Labor and Standards
W. I. Buiten, Tie Down Engineering
C. W. Crossett, Portland Cement Association
E. A. Ferguson, Compliance Systems Publications Incorporated
T. H. Hanna, The University of Sheffield, England
A. F. Howard, Foremost Insurance Company
L. M. Jones, Minute Man Anchors, Inc.
T. W. Klym, Ontario Hydro, Canada
A. Kliener, Fleetwood Enterprises, Inc.
P. C. Knodel, U.S. Department of the Interior Bureau of Reclamation
D. I. McKeown, Iowa State University
M. Neill, Big Valley Industries
J. T. Odom, A. B. Chance Co.
H. Omson, Manufactured Housing Institute
L. W. Perkins, Central Florida Testing Laboratories, Inc.
S. A. Peters, Joslyn Hardware Division
C. A. Ray, Stromberg Carlson Products, Inc.
J. M. Siegel, U.S. Army Natick Research and Development Command
G. L. Smart, Department of Housing and Community Development,
State of California
B. D. Soble, Transtationary Foundation Systems Michigan, Inc.
D. Steel, Housing Engineers, Inc.
R. J. Taylor, Naval Civil Engineering Laboratory, Port Hueneme, CA.
G. G. Watts, Turnset Industries
S. Wengrovitz, Defense Civil Preparedness Agency
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