DEPARTMENT OF THE ARMY
U.S. Army Corps of Engineers
Washington, D.C. 20314-1000
20 August 1992
Letter No. 1110-3-446
Engineering and Design
REVISION OF THRUST BLOCK CRITERIA IN
TM 5-813-5/AFM 88-10, VOL. 5
Purpose. The purpose of this ETL is to provide design
engineers with criteria that will be used in preparing designs
underground water and wastewater piping at facilities for the
Army and the Air Force. This ETL promulgates, as well as
supplements, criteria found in HQUSACE Architectural and
Engineering Instructions, Design Criteria, and shall be
compatible with and reflect criteria found in Air Force Manual
AFM 88-15. This letter is a revision of Appendix C of TM 5-813-
5/AFM 88-10, Vol. 5. The enclosed revision should be used for
thrust block calculations until the criteria is incorporated into
the applicable manual.
Applicability. This letter applies to HQUSACE elements,
major subordinate commands (MSC), districts, and field operating
activities (FOA) having Army and Air Force military construction
and design responsibility.
Discussion. Appendix C of TM 5-813-5/AFM 88-10, Vol 5,
Titled: Water Supply, Water Distribution, incorrectly used
bearing capacity in calculating the lateral restraint for thrust
blocks. In another part of Appendix C, the use of full passive
pressure was incorrectly used to calculate the lateral restraint
for thrust blocks.
Implementation. This letter will have routine application
as defined in paragraph 6C, ER 1110-345-100.
FOR THE DIRECTOR OF MILITARY PROGRAMS: