Design Considerations for Upper Approaches to Navigation Locks

Abstract

Abstract : Upper lock approach guard walls are structural features used by towboats to align with and enter the lock chamber. This report focuses on guard walls located in the upper lock approach. The performance of these guard walls drastically impacts the functional efficiency of any given lock. An efficient guard wall minimizes pilot maneuvering required to bring a tow to rest or near rest on the guard wall and align with and enter the lock chamber. In addition, guard walls are a major component in overall project cost. Criteria for evaluating guard wall performance are general and limited. This report provides guidance so that engineers can design lock approach guard walls that are safe and efficient to the users, while being cost-effective. Both physical and numerical models were used to help research guard wall design and develop guidance for design. A literature review was used to assist in identifying pertinent design needs and to develop the testing and evaluation program. A physical model was constructed so that a detailed evaluation could be performed for selected guard wall designs. A numerical model was used to help rapidly evaluate numerous designs and identify the designs to refine in the physical model.