Investigative Study for Underwater Construction of Lock Floors and Culverts

摘要

This report presents the results of a detailed investigation into the construction and design of lock floor slabs and culverts in an underwater condition (versus in the dry). An extensive review process and discussions with Corps of Engineers Division and District representatives led to the selection of seven plans for inclusion in the intensive investigation. The plans selected were those that offered reasonable expectations for advantageous construction and represented the potential for application to a wide variety of construction technologies for in-the-wet construction. These plans were used to help define the design parameters that might need adjustment due to construction being performed underwater. The innovative plans were evaluated against a set of criteria to identify the advantages and limitations of each plan and to determine its applicability to underwater construction. These criteria included issues related to maintenance, longevity, projected ease or difficulty of implementation (i.e. constructibility), risks to the operation of the lock, cost, environmental concerns, hydraulic efficiency, and construction time. The conclusions presented will permit designers to evaluate various options for constructing floor slabs and culverts with a better understanding of the benefits and the restrictions associated with a given approach. Further investigation is recommended for several design parameters: flotation factors of safety, capacity of piles driven in water, design parameters for high- performance concrete, sheet-pile cutoff walls, and seepage control.