The Panama Canal Authority (ACP) has undertaken the Panama Canal Expansion Program to increase the Canal’s capacity in order to meet the continuous growth in the number of transits and vessel size. The expansion of the Canal involves the construction of two new lock facilities, one on the Atlantic side and another on the Pacific side each with three chambers; the excavation of a new Pacific access channel to the new locks, and widening and deepening of the existing navigational channels and entrances; and increasing the elevation of Gatun Lake’s maximum operating level. Two-dimensional and three-dimensional incremental finite element thermal analyses were performed using ANSYS software to estimate the temperature distribution within the new lock walls, lock heads, crossunders, central connections, and chamber conduits which consist of reinforced mass concrete structures. The estimated temperatures from the finite element model were used to estimate the thermal strains and potential for cracking using procedures outlined in ACI 207. The overall evaluation was used to determine optimal concrete placement temperatures, contraction joint spacing, and to comply with the Employer’s Requirements regarding concrete temperature gradient limitations. Potential for cracking due to drying shrinkage was also evaluated and crack depths were estimated based on the anticipated moisture distribution within the concrete structures. This paper presents the thermal strain, drying shrinkage strain, and cracking potential analyses that have been performed for the new lock walls, lock head structures, and related concrete structures for the Panama Canal Third Set of Locks Project. The results of these analyses were used as key inputs to concrete mixes and their placement temperatures which are designed to withstand for 100 years the deleterious effects of seawater and load cycling of hydrostatic pressures during filling & emptying of lock chambers.
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