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.
Malaysian 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. 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 metres 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 sought-after area, which, with its transportation hub, has become a new-generation central business district. The project 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 metres, with the maximum pile diameter being 1.8 metres.
“Because of the local regulations, the site can work only between the hours of 8 a.m. and 7 p.m.,” he said. “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 metres. 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 metres for the 0.6 metres-wide slurry wall. The cranes are digging the trench in sections of 6.5 metres, each section taking an average of four days to complete.
Loke said that water-soluble polymer is being used to stabilize the borehole, rather than bentonite, as it has a lower environmental impact and is more cost-effective to use on this project.