Assembly and erection of a Goliath gantry crane, Brazil
ALE have assembled and erected a Goliath gantry crane in a shipyard in Estaleiro Paraguacu, near Salvador de Bahia.
The Goliath gantry crane, which has a lifting capacity of 1,800t, measured 134m high and had a span of 142.5m. The project was completed in three phases: upending of the fixed leg, upending of the hinged leg and lifting of the main girder.
For the upending of the fixed leg, nine strand jacks were required in total, with five 500t strand jacks used as wind bracings strand jacks and four 900t strand jacks used for the upending operation.
After installation of the strut construction, weighting 280t, the four 900t strand jacks positioned on the main girder were connected to the strut construction. On the other side, ALE installed a fixed length of strand wires between the strut construction and the fixed leg and on the fixed leg, five 500t strand jacks were installed.
The four 900t strand jacks took the weight of the load to perform the load test, which was executed with a maximum overload of 110%. With the load test passed, a part of the fixed length strand wire was cut, and the system was prepared for the erection of the fixed leg.
Using a crane provided by the client, the fixed leg was lifted to an angle of 24.5 degrees. When the leg was at the angle, the load in the ALE system was increased and taken over from the crane. When the total load was taken over by the ALE system, the rigging between the crane and the fixed leg was disconnected. In a 2 day operation executed in daylight, the fixed leg was erected to a 90 degree angle and was locked in position by the four wind bracing strand jacks in order for the welding works to commence.
After the erection of the fixed leg, the strut construction was removed from the fixed leg, and reinstalled on the hinged leg side.
For the upending of the hinged leg, in total seven strand jacks were required, five were 500t strand jacks used as wind bracings strand jacks and two were 900t strand jacks used for the upending operation.
The strut construction was installed on the hinged leg side, and two 900t strand jacks were installed between the strut construction and the strand jacks positioned on the main girder. Also the fixed length strand wire was connected between the strut construction and the hinged leg.
On the hinged leg, five 500t strand jacks were installed. With the hinged leg already at an angle of 17 degrees, the load in the ALE system was increased and taken over from the crane. When the total load was taken over by the ALE system, the rigging between the crane and the hinged leg was disconnected.
In a two day operation executed in daylight, the hinged leg was erected to a 90 degree angle and was locked into position by the four wind bracing strand jacks. After erection of the hinged leg, the strut construction was removed and transported to a location for disassembly.
The lifting of the main girder started by preparing six 900t strand jacks. The strand jacks were prepared in such a way so that the installation of a single strand jack could be executed by lifting the strand jack including the strand wires and strand guidance.
The strand jacks were installed using two crawler cranes with a boom of more than 160m on top of the fixed leg and the hinged leg. After ALE had installed six 900t strand jacks, there were four 500t strand jacks prepared to act as wind bracers for the main girder lift.
After the installation of all strand jacks these strand jacks were load tested and prepared for lifting the main girder. By using the 900t strand jacks, the load of the main girder was taken into the ALE system. Using the balancing strand jacks mounted on a cantiléver frame, the moment was compensated. The fixed leg and the hinged leg were kept vertical by using the eight wind bracing strand jacks.
When the main girder was lifted free from its supports, it was lifted approximately 16m above ground level. By means of SPMT trailers, the lower trolley was positioned and the main girder was lowered to allow the lower trolley to be installed and connected.
When all works were finished approval was given to lift the main girder to the final position. During a three-day operation executed in daylight, the main girder was lifted to a height of 134m above ground level. After the installation of the main girder and approval for removal and disassembly of the ALE equipment, all materials were removed and loaded into containers for demobilisation.