DEPARTMENT OF THE ARMY
ETL 1110-2-563
U.S. Army Corps of Engineers
CECW-CE
Washington, DC 20314-1000
Technical Letter
No. 1110-2-563
30 September 2004
Engineering and Design
BARGE IMPACT ANALYSIS FOR RIGID WALLS
1. Purpose. This engineer technical letter (ETL) provides guidance for design and evaluation of barge
impact loading on rigid navigation structures such as lock walls, approach walls, channel walls, revet-
ments, and coastal structures. This ETL is applicable to barge impact angles less than 30 degrees
(glancing) and is not applicable for broadside or direct (head-on) impacts and is not intended for flexible
structures.
2. Applicability. This ETL applies to HQUSACE elements, major subordinate commands, districts,
laboratories, and separate field operating activities having responsibilities for the design and evaluation of
civil works projects.
3. Distribution Statement. Approved for public release; distribution is unlimited.
4. References. References are listed in Appendix A.
5. Background/Discussion.
a. The barge impact loads defined in EM 1110-2-2602 are very limited in scope. Therefore since
1993, U.S. Army Corps of Engineers (USACE) navigation structures have been designed and evaluated
using the methods defined in ETL 1110-2-338, Barge Impact Analysis, 30 April 1993. This ETL was
rescinded 30 July 1999. During the design of several recent lock projects, it became apparent that a more
realistic and thorough design method was required. The impact values calculated from the methods pre-
sented in ETL 1110-2-338 were too conservative for design. The existing analytical model in ETL 1110-
2-338 used for the analysis of barge impact loads uses a method that assumed crushing of the barge hull
would occur during every collision with an approach wall. Therefore, under the Innovations for Navi-
gation Projects Research and Development Program, a series of full-scale barge impact experiments
(Patev, Barker, and Koestler 2003a, 2003b) was conducted to capture the normal force of a barge
impacting a rigid lock wall.
b. This ETL will furnish engineering guidance for the development of barge impact forces to be
used in the design of rigid walls at USACE navigation projects. This guidance is based on the results of
full-scale experiments as described in Patev, Barker, and Koestler (2003a, 2003b). An empirical method
(Arroyo, Ebeling, and Barker 2003) has been developed to estimate the barge impact forces for use in the
design and evaluation of rigid structures.
c. The empirical method of Arroyo, Ebeling, and Barker (2003) given in this ETL uses the mass,
approach angle, and the forward and lateral velocities of the barge train as the input parameters to the
model. This empirical method was based on a limited number of low-velocity, full-scale experiments as