Hydraulic Locks

a hydraulic engineering installation that is located between bodies of water with different levels and through which vessels or rafts pass. Locks are built on canals, at hydraulic

Figure 1. Diagrams of a single lock: (1) approach canal, (2) lock chamber, (3) upstream end, (4) downstream end, (5) filling and emptying system, (6) gate, (7) docks, (8) guiding dolphins, (9) a bridge; (Ie) chamber length, (bc) chamber width, (L) lift, (LHP) level of the higher pool, (LLP) level of the lower pool

engineering complexes on rivers, and in seaports whose water area experiences large-amplitude tides.

A sketch of a lock was discovered in the papers of Leonardo da Vinci. Locks were first built in Western Europe in the 16th century and in Russia—on the Vyshnii Volok Water System—in the 18th century. In the USSR, many large locks have been constructed on numerous navigation canals, at reservoirs, and at hydraulic engineering complexes on the Volkhov, Dnieper, Svir’, Volga, and Kama rivers. A substantial number of large locks have been built in Western Europe and in the USA, for example, on the Ohio, Mississippi, and St. Lawrence rivers.

Figure 2. Da Vinci Meter Lock

Figure 3.Tveretsky Canal from the bridge at the mouth of the canal in the Vyshny Volochyok Reservoir.

Figure 4.Mississippi River Lock and Dam No. 16, Illinois, USA

A lock (Figure 1) consists of chambers, ends, and approaches. A lock chamber, in which vessels to be raised or lowered are held, is formed by two longitudinal walls and a floor. As a rule, the walls and floor are made of reinforced concrete. The chamber is sealed by metal gates located within the upstream and downstream ends. According to the number of successive chambers in a lock, a distinction is made between single locks and flights of locks. The number of chambers in a lock depends on the magnitude of the change in water level and on the relief of the terrain. To increase the traffic capacity of a lock, two or more lanes of chambers are built in tandem.

The main dimensions of lock chambers—that is, their length and width—are chosen when a lock is designed. They depend on the category of the waterway, the amount of freight expected to be handled on the waterway, and the size of the largest vessel, train, or convoy the lock is designed to accommodate at one time. The chambers of the largest locks are up to 33 m wide, up to 400 m long, and—in locks in seaports—from 5 to 15 m deep at the sea entrance. Lock chambers are filled or emptied in a prescribed time, from 5 to 15 min, by means of filling or emptying valves and a culvert system.

The ends of a lock are usually massive headworks. In addition to gates, which maintain the difference in water levels and permit vessels to pass through when the levels of adjacent pools are equalized, the ends contain sluice culverts, equipment for eliminating water turbulence, repair and emergency booms, equipment control mechanisms, and automatic control systems. The approaches to a lock’s upstream and downstream ends comprise canals for sectors of a water area that contain both berthing facilities and facilities for mooring ships waiting to be locked and guiding structures for the safe entry of vessels into the lock.

Cite: The Great Soviet Encyclopedia 3rd Edition (1970-1979)