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Year XII n.4 October-December 2017
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Herrenknecht In the City of Angels Bauer The new MC series middle platform
Poste Italiane Spa Sped. Abb. Postale - Stampe periodiche in Regime Libero - CN/FO - Campione Gratuito
Sirive SiriveÂŽ Floating Anchor
At work
Liebherr LB 44-510 000_COVER_PF_ENG.indd 1
A new Liebherr LB 44-510 rotary drilling rig, the manufacturer’s largest, is amongst a fleet of foundations equipment being deployed by Aneka Jaringan on the Sentral Suites project in Kuala Lumpur
25/10/17 14:26
MT • 2017 Media Kit
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Contents
Year XII n.4 October-December 2017
Herrenknecht In the City of Angels Bauer The new MC series middle platform
Poste Italiane Spa Sped. Abb. Postale - Stampe periodiche in Regime Libero - CN/FO - Campione Gratuito
Sirive Sirive® Floating Anchor
Year XII n. 4 October-December 2017
At work
Publisher Mario Giunchedi – mario.giunchedi@scieditrice.com Editor in chief Manuela Cortesi – manuela.cortesi@scieditrice.com Contributors Alberto Bisson, Massimo Chestnut, Porfirio Ferrari, Marianna Senni, Miriam Spada Graphic design Nico Ambrosino – nicoambrosino77@gmail.com Administration Tel. +39 0542 22601 – E-mail: info@scimedia.it Subscriptions Italy: € 36,00 - Other countries: € 60,00 Subscriptions office Tel. +39 0542 22601 – E-mail: abbonamenti@scimedia.it Print GRAFICHE MDM - Forlì
At work > Liebherr
Liebherr LB 44-510 000_COVER_PF_ENG.indd 1
A new Liebherr LB 44-510 rotary drilling rig, the manufacturer’s largest, is amongst a fleet of foundations equipment being deployed by Aneka Jaringan on the Sentral Suites project in Kuala Lumpur
25/10/17 14:26
Liebherr’s biggest rotary drilling rig begins work on Kuala Lumpur project John Melegatti p. 2 Foundations > Bonatti at OMC
Ten years of Bauer duty-cycle cranes: BAUER Maschinen GmbH presents the new MC series middle platform John Melegatti p. 6
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At work > Herrenknecht
Herrenknecht in the City of Angels Massimo Chestnut
p. 10
Technologies > Sirive
Sirive® Floating Anchor Alberto Bisson
p. 14
Shipping Spedizione in Abbonamento Postale – D.L. 353/2003 (conv. in L. 27/02/2004 n. 46) art. 1, comma 1, CN/FC/004 Registration Autorizzazione Tribunale di Ravenna n. 1286 del 25/10/2006 Iscrizione ROC: 29737
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At work > Liebherr LB 44-510
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Liebherr’s biggest rotary drilling rig begins work on Kuala Lumpur project A new Liebherr LB 44-510 rotary drilling rig, the manufacturer’s largest, is amongst a fleet of foundations equipment being deployed by Aneka Jaringan on the Sentral Suites project in Kuala Lumpur John Melegatti
Liebherr LB 44
The biggest rotary drilling rig in the Southeast Asian market
M
alaysian foundations and geotechnical specialist Aneka Jaringan Sdn Bhd is using a newly delivered Liebherr LB 44-510 rotary drilling rig, the biggest and most powerful drilling rig in the Liebherr range, for pile boring on the Sentral Suites project in Kuala Lumpur. The LB 44 is working alongside a new Liebherr LB 36 rig, the second largest machine in the range. Also part of the Liebherr fleet on the site are two duty cycle crawler cranes, an HS 8100 HD and an HS 855 HD, which are being used for slurry wall trenching. The two crawler cranes are being used to excavate 600 m of slurry wall that surrounds part of the site, with the two rotary drilling rigs boring the holes for 366 piles. Sentral Suites is a landmark project in the KL Sentral district, and is billed as probably the last major residential development in this much soughtafter area, which with its transportation hub has become a new-gen-
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At work > Liebherr LB 44-510
eration central business district. The project, which is being developed by MRCB Land, will include three towers, the tallest of which is 45 storeys. Aneka Jaringan is undertaking the foundation and excavation contract: the company moved onto the site in the middle of January 2017 and is working to an 18-month schedule, due for completion in July 2018 The LB 44-510 is one of the first of this model to have been delivered to Southeast Asia. Both the Liebherr rotary drilling rigs were delivered with extensive training package for Aneka Jaringan’s operators and service personnel. Loke Kien Tuck, director of Aneka Jaringan, said that both the LB 44 and the LB 36 are boring to depths of a maximum 35 m, with the maximum pile diameter being 1.8 m. “Because of the local regulations the
site can work only between the hours of 8 am and 7 pm,” he says. “We therefore have to work quickly, and the two machines are proving to be very fast. The ground is quite hard, being mostly silty sand, and we are taking between five and six hours to bore down to between 30 and 35 m. That means we can complete the boring and casing installation in one day, and then pour the concrete the following morning.” The Liebherr HS 8100HD, equipped with a mechanical slurry wall grab, and the HS 855 HD duty cycle crawler crane, equipped with a hydraulic slurry wall grab, are excavating to a maximum depth of 22 m for the 0.6 m width slurry wall. The cranes are digging the trench in sections of 6.5 m, each section taking an average of four days to complete. Mr Loke says that water-soluble polymer is being used to stabilise the
HS 855 HD and HS 8100 HD working on the trench excavation, while the LB 36 bores a pile hole
borehole, rather than bentonite, as it has a lower environmental impact and is more cost-effective to use on this project.◀
INFO For more than 60 years, Liebherr’s range of products and services has been broad and sophisticated. Its design and technology is orientated around practical deployment scenarios throughout the world. Continually growing innovative strength and an uncompromising commitment to quality safeguard the highest level of benefit to the customer in all product areas.
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25/10/17 11:51
Foundations > Bauer
A customer of BAUER Maschinen GmbH in Shanghai recently achieved a mixing depth of approximately 80 m with a cable-guided S CM mounted to an MC 64 duty-cycle crane in a low-headroom configuration. This is more than has ever been achieved before with an SCM unit
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Ten years of Bauer duty-cycle cranes: BAUER Maschinen GmbH presents the new MC series middle platform MC duty-cycle cranes from Bauer are truly universal machines for specialist foundation engineering John Melegatti
M
C duty-cycle cranes from Bauer are truly universal machines for specialist foundation engineering. Thanks to their massive steel structure and robust booms, they are the perfect foundation for a wide variety of mounting options,
e.g. cutters or grabs. There are a large number of Bauer MCs currently operating all around the world. It all began at the Bauma 2007 in Munich, when Bauer introduced the first MC 32 duty-cycle crane model – the start of a modern success story. The aim of developing and construct-
ing the company’s own duty-cycle cranes was to close a gap in the market. A durable mechanical solution was to be created for specialist foundation engineering applications that still lacked an optimized carrier. In record time, the first duty-cycle crane completely designed by Bauer was
In May 2017,
Bauer Maschinen introduced the new MC 86 duty-cycle crane to the public
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Foundations > Bauer
developed, and the MC 32 as a compact base carrier for hydraulic grabs was presented to the public in 2007. It was followed in the very next year by the introduction of the MC 64, which was optimized as a 100 t-class duty-cycle crane especially for use as a cutter carrier. And the MC 128 was finally introduced to the market in 2009, which has since proven its strength as a carrier for heavy cutting systems, especially in major specialized projects. The 2011 model range was further enhanced by the introduction of the MC 96, the development of which was largely based on the MC 64 uppercarriage platform. Bauer Maschinen really hit the mark with its customers on this model: “The MC 96 has become a true top seller. Now, half of the duty-cycle cranes we build and sell involve this model,” confirmed Steffen Fuchsa, Product Manager for duty-cycle cranes at BAUER Maschinen GmbH. In May 2017, BAUER Maschinen GmbH finally introduced its newest generation from the MC range: the MC 86. This replaces the MC 64 small cutter carrier in Bauer’s duty-cycle crane range. In comparison to the MC 64, it has an increased payload of 110 t thanks to a reinforced undercarriage and additional ballasting options. Additional features include new 30-ton free-fall winches with high speeds and cable capacity, a complete overhaul of the rig to accommodate a main cable diameter of 34 mm, and a new universal mast head for gripping and lifting work. An optional fly jib allowed a maximum payload of 35 t on the auxiliary line; the new facelift cab is equipped with B-Drive and Klimatronic as standard. Bauer duty-cycle cranes are extremely versatile. In addition to pure lifting operations, they are also used as base carriers for such equipment as cable and
About Bauer The BAUER Group is a leading provider of services, equipment and products dealing with ground and groundwater. With over 110 subsidiaries, Bauer can rely on a worldwide network on all continents. The Group’s operations are divided into three forward-looking segments with high synergy potential: Construction, Equipment and Resources. The Construction segment offers new, innovative special foundation techniques alongside the conventional ones, and carries out foundations, excavation pits, cut-off walls and ground improvements worldwide. In the Equipment segment, Bauer is the world market leader providing a full range of specialist foundation engineering equipment and equipment for exploration, development and exploitation of natural resources. In the Resources segment, Bauer focuses on highly
hydraulic grabs, vibrators, cutters, the Bauer Flydrill, the Flying Vibro or drop weights, which are used for dynamic soil compaction. It is also possible to mount casing oscillators and use leader-mounted equipment. When developing the MC, a special focus was always placed on seamlessly combining the design with Bauer-specific special equipment in particular. In the process, the massive steel structure and robust boom have proven especially successful. Both have been specially designed for high dynamic continuous loads, e.g. dynamic soil compaction or heavy grab work. Another characteristic feature of Bauer’s MCs is the free-fall winches, which mechanically separate the frictional connection between the drum body and the drive when necessary. The cable is
innovative products and services in the areas of water, environment and natural resources. Bauer profits enormously from the collaboration of its three business segments, enabling the Group to position itself as an innovative, highly specialized provider of products and services for demanding projects in specialist foundation engineering and related markets. Bauer therefore offers suitable solutions to the world’s greatest challenges , such as urbanization, the growing infrastructure needs, the environment, as well as water, oil and gas. The BAUER Group was founded in 1790 and is based in Schrobenhausen, Bavaria. In 2016, it employed about 10,800 people in around 70 countries and achieved total Group revenues of EUR 1.6 billion. BAUER Aktiengesellschaft is listed in the Prime Standard of the German Stock Exchange.
unwound under a suspended load, allowing the drum body to rotate freely. “Our free-fall winches have a large design in both width and diameter in order to ensure large cable capacity on the drum, and secondly to minimize cable wear as much as possible,” explained Steffen Fuchsa. Bauer duty-cycle cranes are equipped with powerful diesel motors. For example, the MC 76/86/96 middle platform series is equipped with a 570 kW engine (available as an optional Tier 4 final engine). Compared to a lifting crane of the same load bearing capacity, this engine provides double or even triple the performance. “This performance level is necessary for both winch operation and for the hydraulic equipment,” said Steffen Fuchsa.
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Dynamic soil compaction
in Abu Dhabi with a BAUER MC 96. In roughly three months, the duty-cycle crane performed about 1,000 working hours, making 50,000 strikes with the approximately 20 t drop weight
In the many years since the development of the first duty-cycle crane models, Bauer Maschinen has incorporated a great deal of new features and improvements in the MCs. This progress has led to a considerable reduction in noise and fuel consumption as well as to a significant improvement in safety – including patented special solutions. Specially developed noise protection kits can result in noise reduction levels of 3 dB (A), cutting noise emissions in half! This is achieved using a number of technical measures, such as optimized airflow, a controls system for the cooling unit coupled to speed, and the Smart Eco Mode for the diesel engine. This is closely related to implementing Energy Efficiency Power technology (EEP) in the newest MC generation,
which is primarily involved in introducing the closed winch system. On one hand, this design ensures especially efficient winch drive and, on the other, allows the winches to be operated independently of other functions. The new MC duty-cycle crane models are also equipped with a number of features in terms of work safety. To name just a few, these include additional hand rails and guard rails for safe mounting on the uppercarriage, safety sensors and camera systems, a patented monitored rope anchorage with overload protection or a special personnel safety system that effectively protects the technician from major injury during boom assembly. Additional features, some of which are optional, include wireless remote
control, swivel angle or boom angle limitation, a hydraulic counterweight lock, and a fire extinguishing system. Thanks to the refrigeration kit or additional air-conditioner, Bauer MCs can be used with ease in regions experiencing extreme climatic conditions. Finally, the flexibly mounted and comfortable, ultra sound-proofed driver cabin offers an excellent view of the work area. “The unique strength of our MC dutycycle crane lies in its consistent focus on the requirements of specialist foundation engineering,” says Dieter Stetter, Managing Director of BAUER Maschinen GmbH. “By the end of 2017, we will have sold well over 200 of our MCs – all within ten years of its launch in 2007.”◀
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At work > Herrenknecht
Herrenknecht in the City of Angels Tunnel boring machines from Herrenknecht work at three projects In Los Angeles, part of the strategic subway extension in L.A. to relieve the traffic above ground Massimo Chestnut
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In April 2017 EPB Shield »Harriet« completed its tunnelling mission totaling 3.2 kilometers under Los Angeles as scheduled. The new Crenshaw/LAX Transit Corridor will shorten inner city travel times and improve the connection to international airport LAX
L
os Angeles, the city of angels, suffocates in traffic during rush hour. For this reason the Los Angeles Metropolitan Transportation Authority (Metro) is pushing ahead at full speed with the expansion of local transport links. In the coming years, the existing metro rail network will be expanded in a number of different places. The latest example is the Crenshaw/LAX Transit Corridor. The nearly 14 kilometer long new light rail route will improve the connection between the urban centers of Crenshaw and Inglewood as well as the region around Los Angeles International Airport (LAX). LAX passenger numbers alone show the high demand for public transport capacity: in 2016, more than 80 million passengers were processed – and the trend is rising. Between May 2016 and April 2017 the Earth Pressure Balance Shield (EPB) »Harriet« worked its way forward underground for a section of the Crenshaw/LAX Transit Corridor. The Herrenknecht TBM (Ø 6.51m) first excavated a 1.6 kilometer long tunnel between the future stations of Expo/ Crenshaw and Leimert Park. It was then disassembled and transported back to the launch shaft for the second, parallel section. In April 2017 »Harriet« completed her mission below Los Angeles with the second breakthrough in the target shaft at the Leimert Park station. With a 24 hour best performance of 43 meters a new record in mechanized tunnelling with a subway sized EPB Shield was set for the city of Los Angeles – four more times 40 or more meters were created within one day. Thanks to weekly best performances of 170 meters the Crenshaw/LAX Transit Corridor is expected to go on line on schedule in 2019.
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At work > Herrenknecht
From the beginning of tunnelling in April 2016 until April 2017, hightech machine »Harriet« built two tunnels and covered 1,600 meters for each of them. For firedamp protection in the gaseous soils under L.A. the TBM design is explosion-protected
Meanwhile, in February 2017 the Earth Pressure Balance Shield »Angeli« got under way. The TBM is boring a section of the Regional Connector Transit Corridor. It will link the existing Gold, Blue and Expo Metro Lines to new and faster direct connections. From 2020 this will allow locals and visitors to travel north-south from Azusa to
Long Beach and east-west from East Los Angeles to Santa Monica without having to change. »Angeli« has just finished the first of two 1.7 kilometer long tunnelling routes. On July 18th she reappeared in the target shaft at 4th Street. Next she will dig a parallel tunnel with the final breakthrough scheduled for the end of the year.
One of the greatest challenges in mechanized tunnelling under L.A. are the possible gas deposits. In order to master these safely, the contracting joint ventures have opted for special technology from Herrenknecht. The electrical components in »Harriet« and »Angeli« are explosion-protected so that safe tunnelling can be realized at all times. This measure has previously proved its worth worldwide in various reference projects. Despite the complex geological conditions and the inner city drive beneath densely populated areas, thanks to the active communication of Metro the two Earth Pressure Balance Shields have
Back in 2006, the two Herrenknecht TBMs S-297/298 successfully completed their drives to expand the Gold Line in Los Angeles. At that time too, both machines featured an explosion-protected design due to the presence of gas
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The machine S-952 »Angeli« for the construction of the Regional Connector Transit Corridor has just finished driving the first tunnel section on July 18th. The EPB Shield was built for the project at the US subsidiary Herrenknecht Tunnelling Services Inc. in Seattle
already gained a certain cult status with the population of L.A. The muchread Twitter account of »Harriet« was closed after its breakthrough, »Angeli« continues to communicate with the interested population (account: Angeli@regionaltbm). To name the machines, Metro ran a competition for school children. From the many suggestions, the majority of the more than 50,000 online voters chose »Harriet«, thereby honoring anti-slavery activist Harriet Tubman. »Angeli« also comes from the pen of a school child. The term comes from Latin and means “angel”.
In the meantime, designers and engineers at the Herrenknecht headquarters in Schwanau are already working on the next order for Los Angeles. The existing Purple Line is also planned to grow by 14.5 kilometers and seven stations. To this end, in both the spring of 2018 and the spring of 2019 two additional Herrenknecht Earth Pressure Balance Shields each are to be launched in the USA. In just a few years the four machines will produce over 11 kilometers of high quality tunnel tubes. A decade ago, under similar conditions two EPB Shields from Herrenknecht had already built a total of 4 kilometers of tunnel for the expansion of the Gold Line. Herrenknecht technology in Los Angeles is
thus already a real success story. To be continued.◀
A total of six Herrenknecht tunnel boring machines are realizing stateof-the-art metro tunnels for the Los Angeles metro rail extension in several areas of the metropolis
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Technologies > Sirive
SiriveÂŽ Floating Anchor SiriveÂŽ floating anchor: results of an italian research program for landslide stabilization Alberto Bisson
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Sirive® Floating Anchors with Sirive® Composite Self-drilling Bars up to 3000 kN ultimate strenght in Cischele landslide (Recoaro Terme, Italy).
D
ue to its weather-climatic, geological and geomorphological setting, Italy is particularly subject to geo-hydrological hazard. New alarms intensify during exceptional rainfalls. Therefore, the research for innovative and cost-effective solutions for risk mitigation and landslide stabilization has great scientific and socio-economic relevance. Sirive® R&D division, affiliated to the most important research institution, set up an innovative costeffective passive reinforcement, the so called Sirive® Floating Anchors with Sirive® Special Composite Self-Drilling Bar.
The Sirive® Composite Anchor Self-drilling anchor bars are a good alternative to traditional nailing and anchor techniques. To expand their application field and improve their mechanical behaviour, Sirive R&D developed a special composite bar, coupling a traditional carbon steel bar with tendons. This is achieved by inserting the tendons in the inner cavity of the bar, then cementing with a special grout.
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Technologies > Sirive
The installation of a tendon locking head completes the so called Sirive® Composite Anchor system. The composite anchor installation follow these steps:
1.
Installation of the self-drilling bar: same way of a normal self-drilling bar with a disposable drilling bit; the bar is fully grouted both inside and outside, thus developing a frictional soil-grout interface.
2.
3.
Installation of the tendons: before the inner grout hardening, the harmonic steel strands are inserted into the cavity of the self-drilling hollow bar. Tendons are coated, thus providing a foundation length and a free length. Eventual pre-tensioning of the tendons: after the tendons foundation has been created, and after grout hardening, the strands can be tensioned and connected to the external anchoring structure by a special locking head. Thus, different configurations can be obtained: an “active” composite anchor whether the tendons are
Sirive® Special Composite Self-Drilling Bar up to 3000 kN ultimate strenght: Sirive® S76 coupled to 7 tendons (cross section)
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pre-stressed, a “passive” composite anchor whether the tendons are just connected to the bar without pre-stressing. Composite anchor provides lots of geotechnical and technological advantages: ▶ minor cost; ▶ high ultimate tensile strength; ▶ high durability (minor cracking, better protection from corrosion); ▶ easy transport and quick installation; ▶ anchor length adaptable to the geological in situ conditions; ▶ higher flexural inertia and good continuity given by the strands to the full reinforcement (improved if compared to simple coupling sleeve). Composite anchors can be used in consolidation of excavations, soil and rock slope reinforcements, foundations, and landslide stabilization too.
The Sirive® Floating Anchor for landslide stabilization Passive reinforcements represent a cost-effective technique for slowmoving landslide stabilization. Since in these applications the axial and bending forces developed in the reinforcements may be huge, composite anchors are perfect because they can reach high strength reducing installation time and costs.
Sirive® Floating Anchor technique, developed as an improvement of the Soil Nailing, consists of installing passive sub-horizontal reinforcements in unstable slopes, to increase the resistant forces contrasting the sliding. The reinforcements are passive Sirive® Composite bars grouted in the full length, with a sufficient foundation in the bedrock, and coupled with individual external concrete slabs (i.e. the “floating” element).
Scheme of Sirive® Floating Anchor system with floating slabs englobed in moving slopes and a foundation in resistant soil
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Technologies > Sirive
SiriveÂŽ Floating Anchors with SiriveÂŽ Composite Self-drilling Bars up to 2000 kN ultimate strenght in Val Maso landslide (Valli del Pasubio, Italy)
If some slope movements occur, axial forces in the passive reinforcements develop because of the shear stresses growing at the soil-grout interface in the slow-moving mass: consequently, the axial forces contrast part of the forces inducing the instability, thus reducing the landslide evolution process until it completely stops. Since the axial head force at the external slab is small, the system does not require a continuous facing, and, whether the slope deforms, the slabs is englobed inside the soil. Since the floating anchor is a modular and flexible technique, it offers the advantage to support the slope deformations without losing effectiveness, slowing down the evolutional process until it completely stops.
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Sirive® Floating Anchors with Sirive® Composite Self-drilling Bars up to 2000 kN ultimate strenght in Gisbenti landslide (Valli del Pasubio, Italy).
The research program A research program developed by University of Padova (Italy), Politecnic University of Turin (Italy) and University of Agriculture in Cracow (Poland) analysed the components of the floating anchor both in physical and numerical models. The theoretical formulation describing the punching resistance of the floating slab and a full design method have been developed. The real-scale behaviour was also analysed by installing and monitoring some test sites, i.e. real landslides in Italy and Poland stabilized by Sirive® Floating Anchor. The research resulted in proving the greater efficiency at a lower cost respect to traditional techniques, such as gravity retaining walls, sheetpile walls or structural wells. The main advantages of floating anchor technique are the flexibility associated
with the ability of the system to adapt to slope deformations without losing functionality. The modularity of the elements makes the application particularly attractive for the stabilization of slow moving slopes in subsequent construction phases. The technique perfectly integrates with the observational method, which allows subsequent steps, integrating the works in modules according to monitoring observations.
Results in real landslides The research partnership with professionals and Soil Protection public agencies allowed the design and execution of some floating anchoring operations in real landslides and their monitoring. Four landslides have been selected in Italy and one on the Carpathians in Poland, where the technique has been experimented.
Sirive® floating anchors were installed and monitored, thus proving the effectiveness of the technique. A full description of the real cases and monitoring results is provided on the project official website www.ancoraggioflottantesirive.com or contacting Sirive R&D division.◀
INFO AUTOPERFORANTI SIRIVE® Via Fogazzaro 71, 36073 Cornedo Vicentino (VI) - Italy Tel. +39 0445 953513 Fax +39 0445 459406 barre@sirive.it www.sirive.it
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