Maracaibo is not situated in a seismic area, but it is not immune to shock waves from earthquakes in adjacent regions. As is written in the book, "the employer required that, should one span of the bridge be affected by an earthquake disturbance, the adjoining spans would not also suffer damage". Therefore, the design provided for all members to be of the statically determinate type.
In order to complete the 8, 678m long bridge in the short contract time, it was essential that, wherever possible, uniform members should be used. This enabled numerous units to be prefabricated at a plant on shore, specially equipped for the purpose.
Site seen from the air.Starting from the low eastern shore, the structure features a 406m long embankment, after which come twenty 36.60m spans. This effective span was decided upon for the railway and road bridge, and had to be adhered to because the foundations had been completed when it was decided that the bridge should be for road traffic only. Then follows a section having seventy-seven 46.60m spans, initially, this is 5.5m above water level and then rises at a gradient of 0.4 per cent and ultimately at a gradient of 2.47 per cent to reach a height of 24m. Up to this point the 46.60m spans provide openings of balanced proportions. But if this span had been retained for the next section of the bridge, extending to a height of 50m, the design would have been monotonous and the piers disproportionately high.
Therefore, the span was increased to 85m, and instead of plain piers, V and H trestle piers were employed; on top of them were mounted 39m long caps, thereby permitting the continued use of the 46.60m girders as suspended spans. As the height of the bridge increases, the V shape of the trestle piers is gradually transformed to an H by lengthening the pier legs in their lower parts. The size of the caps, V-sections of the piers and cross beams remains constant. Consequently, only minor changes were required in the centering, shuttering and reinforcement, from one pier to another. This facilitated and accelerated the construction operations.
Two special trussed steel centering were fabricated for the caps. They had high-quality plywood shuttering. The shuttering and practically all the reinforcement were assembled on these centering on land, and a complete service girder was placed in position with the aid of large floating cranes. It was extremely difficult to bridge the navigation openings of 200m waterway and 45m headroom by a reinforced concrete structure.
Handling a 6m long pile.The Ajax 250-ton floating crane handles 46.60m precast girders. The Giraffe 125-ton floating crane places a service girder on one of the two highest piers of the 85 m spans.Trestle pier towers 49.50m into the sky. Climbing shuttering for V-shaped piers in place.Concreting pier cap.
Structures 22, 23, 24 and 25 under construction.
A service girder is being raised into position. To this end, for the first time in the world, five large tied cantilever bridges of concrete, having 235m spans, were designed and constructed. The inclined ropes for the cantilevered girders pass over 92.5m high reinforced concrete towers. Extensive investigations and calculations were necessary to determine the complex system of forces in the ropes, cantilevered portions and reinforced concrete towers."[22]
Bridge ropes were pulled on the catwalks up to the roller saddle and down the other side.
8. Bridge Administration (1962-1990) Forty months after the works had begun, the bridge was ready to start operating.[23].
From 1962 until 1990, "the management of the bridge was done by the National Government through the Ministry of Finance, who performed the activities of collection and administration of funds, and by the Ministry of Public Works, responsible for maintaining the structure.
In December 1989, the Congress of Venezuela transferred directly to the states the conservation and use of all the roads, bridges and highways in their territories. On July 26, 1991, the Zulia State Legislative Assembly enacted the "Law according to which the Zulia State assumes the Conservation, Management and Use of the bridge General Rafael Urdaneta over Lake Maracaibo."[24]
14. Preservation Policies (1990-2009) According to a concern for keeping in optimum condition the bridge structure, the Zulia State Government assumed as a priority the allocation of investments for the rehabilitation and continuous improvement of the bridge's conditions.
The main objective was to restore the structure to its "brand new" condition, taking into account the bridge's original load capacity and levels of service."[25]
15. Maracaibo Bridge is Falling Down In May, 2009, the Venezuelan Government decided to re-centralize again the management of the bridge. Since then, an increasing deterioration began. This decay lasts until today. Minor and major maintenance "is only performed to correct problems and as a reaction to crisis."[26]
In 2010, the Colegio de Ingenieros de Venezuela publicly expressed their alarm. They said that the bridge is in an emergency, "due to a crack in its structure which has yielded several centimeters." In this regard, they asked for its immediate closing: "A comprehensive review of the entire structure is required, and can no longer be postponed." And they warned that "a partial collapse might occur." The main problem is "the degradation of concrete in several of the bridge parts" and the decay of the ropes. Also, "the falling parts of concrete pieces, leaving the steel uncovered."[27] Corrosion damage is practically everywhere.
Traffic in the bridge over the lake has increased enormously, but as the control scales are damaged, no one surveys the number of vehicles going upon it today. A very dramatic situation for a structure designed for a maximum of 20,000 vehicles per day, which now is said to be having 40,000 per day.
Local fishermen and marines from the Lake Maracaibo also do their own alarm call to the national and international community: "If you see the bridge form below, you would not want to pass over it."
Acreditados (f. Docomomo VE, 2016) 
All set! (f. Docomomo VE, 2016)
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