3D animation TBM S574 "Martina" (eng)

[Music] you how does the world's largest tunnel-boring machine work perhaps the easiest way to answer this question is to demonstrate how the Heron connect s 574 earth pressure balance shield is being used in the Galleria Sparta project you as part of the three lane widening of the a1 autostrada in Italy the machine is boring a 2.5 kilometre tunnel section between Bologna and Florence the route model shows the s-shaped line to the being tunneled you after completion of the first four the machine is turned and then drives the second boer parallel to the first the local geology comprises mainly clay argillite sandstone and limestone by strata containing methane the machine has been specially equipped to deal with this problem the s 574 is an E Phoebe shield with an outer diameter of 15 point 55 meters and an overall length of 120 meters with its rotating cutting wheel the tunnel-boring machine removes the material with the tunnel face a screw conveyor then moves the excavated soil to conveyor belts behind the EPB shield while all this is going on hydraulic cylinders continuously drive the tunneling machine forward protected by the shield skin the reinforced concrete segments are set in place when a complete ring has been built the machine is able to push off from the newly installed tunnel ring and continue boring into the ground the 105 meter long backup houses all the logistics equipment needed to operate the entire system all the key information with the current tunneling parameters is fed into the central control cabin here it is visualized on screens for the TBM operator who is able to monitor the largely automated processes the way an EPB shield works can essentially be divided into two phases the tumbling phase and the ring building phase in the tunneling phase hydraulic thrusts cylinders apply a pressure of up to 500 bar to push the cutting wheel against the tunnel face it rotates at speeds of up to two revolutions per minute 50 hydraulic motors developing as much as 94,000 100 kilonewton meters torque power the cutting wheel via the gear rim the high-pressure into can able the high-strength steel disc cutters and cutting knives to easily remove the material with the tunnel face during shield drives an unstable ground face support pressure is generated to counteract any loss of stability at the tunnel face on an earth pressure balance shield the soil excavated by the cutting wheel is used to support the tunnel face during advance the excavation chamber is permanently completely filled preventing settlement on the surface and the build-up of explosive mixtures to achieve a state of balance the face support pressure is transmitted from the hydraulic thrust cylinders to the loose soil through the bulkhead thereby prevent uncontrolled penetration into the ground the internal status in road through the soil mixture while foam can be injected via nozzles to ensure the required consistency is maintained a screw conveyor now removes the tree from the invert area of the excavation chamber to a conveyor belt the screw conveyor is powered by four hydraulic motors delivering 1,200 kilowatts the speed of rotation regulates the volume of soil removed from the excavation chamber and adjusted to the advance speed the aim is to keep a balance between the volume of soil removed by the screw conveyor and the volume of soil being produced by the advance of the EPB shield this makes it possible to ensure optimal support of the tunnel face one of the risks inherent and tunneling along the route is the occurrence of explosive firedamp measures have to be taken to eliminate the risk of explosion as a safety precaution the conveyor belt is housed from a screw conveyor discharge to delivery to the cross belt conveyor on gantry number three continuous feed of large volumes of fresh air greatly reduces the gas content inside the bore further mixing is carried out at the open outlet the machine is fitted out with explosion protection equipment and the concentrations and gas tightness of the system are continuously monitored this allows our control deck in process even in sections where there is a possibility of the occurrence of firedamp once the tunnel phase has been completed cutting wheel and screw conveyor are stopped the ring building phase now commences under atmospheric pressure conditions in the shield area a complete Tunnel ring consists of several segments called lining segments these prefabricated reinforced concrete elements are precision produced on the surface and especially set up production plant and following quality inspection are taken into the tunnel on carriages at the front end of the carriage the segments are individually raised by a special transfer crane and placed on the segment feeder which brings the segments to the front area of the tunnel here the segment's weighing several metric tons are lifted by vacuum plates on the erector a hydraulically controlled crane arm and moved into place the erector runs on two rails and can be moved rotated and telescoped each complete tunnel ring is made up of a numb standard segments together with to counter key segments and one key segment the segment's are always installed in the same sequence the erector raises the segment off the segment feeder the hydraulic thrusts Illin retracted to the relevant installation position using remote control the segment is then positioned by eye exactly against the last installed ring the hydraulic cylinders are now extended again to secure the segment in its position the segment is then bolted to the previous ring the segment's continued to be placed on alternate size finally the key segment with slanted longitudinal joints provides inherent locking in the ring completing the ring building phase ready for the next tunnelling phase to begin a fast motion sequence illustrates the two working phases of the TBM the tumbling phase and ring building phase continuously alternate so that the tunnel grows ring by ring under optimal conditions it is possible to achieve more than 100 meters advance weekly this involves shifting up to 20,000 cubic meters of excavated material and installing well in excess of 500 segments you harren connect earth pressure balance shield normally in their element in cohesive soils of clay and silt with low levels of water permeability however EPB technology also allows successful tunneling in loose sand and gravel soils and solid rock the technology has been proven worldwide on an extremely diverse range of traffic tunneling projects the range of applications of this type of machine is now being even further extended with the use of the 15 point 55 meter diameter Herron Connect EPB shield on the galerias barbell project [Music] you [Music]

Channel: Toto Holding

Views: 776,289

Keywords: toto, costruzioni, grandi opere, infrastrutture, infrastructure, construction, excavation, tbm, epbm, epb, earth pressure balanced, tunnel, tunneling, tunnelling, galleria, tunnel boring machine, fresa, megafresa, maxifresa, talpa, herrenknecht, scavo meccanizzato, variante di valico, autostrada del sole, motorway, a1, sparvo, guinness, world record, s574

Id: MJP5qia9Py4

Length: 12min 1sec (721 seconds)

Published: Wed Feb 27 2013