Sandvik essential equipment on major Hong Kong infrastructure development

The new Liantang/Heung Yuen Wai BCP will be the seventh land crossing between Shenzhen and Hong Kong, with the associated contracts being the last of four major civil engineering contracts awarded under the BCP project. When complete it is envisaged that people and cargo flows across the boundary will become smoother and more efficient, with the BCP will playing a strategic role in sustaining the long-term economic growth of the area.

There are currently two existing BCPs (Boundary Control Points) on the eastern side of the New Territories between China and Hong Kong. These are located at Man Kam To and Sha Tau Kok being mainly used to access eastern Shenzhen and Guangdong. All cross-boundary traffic travelling from these BCPs has to travel through busy local roads in Hong Kong and Shenzhen before joining the major highway systems. This often leads to traffic congestion and hold-ups. The HK 25 billion dollar Liantang/Heung Yuen Wai Boundary Control Point has been designed to alleviate these problems, connecting the expressway systems in Hong Kong and Shenzhen, thereby reducing the travelling time between Hong Kong and eastern Guangdong, as well as southern Fujian and Jiangxi.

The new BCP will help redistribute the cross-boundary vehicular traffic amongst the crossings in the east, helping to alleviate traffic hold ups at the Man Kam To and Sha Tau Kok BCPs. Additionally it will provide room for the expansion of the existing BCPs so that the overall handling capacity and the quality of service of the BCPs in Hong Kong will be enhanced. In addition four interchanges along the connecting road at the junctions with Fanling Highway, Sha Tau Kok Road, Ping Yuen Road and Lin Ma Hang Road, will be constructed in order to improve access for local residents with a new road connection being built.

Tunnels, highways and viaducts

One of the major areas of development for the new BCP will see the construction of a new highway, viaducts and a 700m road tunnel. The works are scheduled for completion by the end of 2018 with a budgeted cost in the region of HK 6 billion dollars. Termed 'Contract 6', this part of the BCP will be undertaken by a joint venture comprising of three companies: China Road and Bridge Corp (CRBC) from mainland China, Continental Engineering Corp (CEC) from Taiwan and Hong Kong based Kaden Construction Ltd: the CRBC-CEC-Kaden JV.

When finished, 'Contract 6' will provide a new 4.6km long dual two-lane trunk road (with about 0.6km at grade roads), 3.3km of viaducts and a new 0.7km tunnel. These will connect the Sha Tau Kok Road Interchange to the new BCP, and will also see associated environmental mitigation measures, landscaping, as well as new drainage/sewerage, utilities and waterworks.

A partnership to deliver results

'Contract 6' is seen as a project requiring a multifaceted approach to construction, requiring the use of many different techniques in order to deliver the project on time, and to budget. In order to achieve this CRBC-CEC-Kaden JV has been keen to utilize the equipment and services of a globally renowned company who could not only provide the equipment needed, but also support their activities in the field. To this end the JV has little hesitation in turning to Sandvik Mining and Rock Technology for equipment, and vitally, support.

"We realized that Contract 6 would require some highly specialized equipment that will need to be supported by highly trained and effective people." So says Mr. K Y Chow, Construction Manager for the JV. "We needed surface drill rigs for open cut of the hills by drill and break. Tunneling jumbos for the excavation of the tunnel, and then vitally, high quality mobile crushers to crush the excavated rock," he adds.

Advanced drilling technology

The first part of Contract 6 required the JV to invest in three Ranger DX800 surface drill rigs. A Ranger DQ500 and Ranger DX700 were also working at this site. The drill rigs were used for the open cut of the hills by drill and break. Drill and blast was not possible as blasting was not permitted on the type of hill cut along the highway. The Ranger DX800 however proved to be highly suited to the application and progress was rapid.

The Ranger DX800 used has been redesigned to accommodate new features which have been developed based on customer feedback. One of the new features is the revolving superstructure enabling large drilling coverage from the standard 17.6m² (189ft²) to a USA standard 26.4m² (248ft²). While able to rotate, the rig's stability is guaranteed thanks to its innovative structure, keeping counterweight at all times on the opposite side of the boom. In addition to these, the rig features, for example, a THC700 drilling control system that automatically adjusts to changing rock formations and sends an optimal amount of power to the rock. This has been designed to ensure smooth rotation, solid rock contact and fast penetration in different rock conditions. Operating costs significantly reduce due to the rig's low fuel consumption rates that are achieved with a new advanced eco-package and engine RPM adjustment. Another enhancement is improved tramming force, which has increased by over 10%.

For the actual excavation of the dual two-lane tunnel Sandvik was again chosen to supply equipment with three DT1230i and a DT820-SC tunneling jumbos being selected. These were required as each tunnel is 14m wide and 11m high for two lines of traffic on the two main tunnels as well as some small cross passage tunnels.

The DT1230i is a computer-controlled three-boom electro-hydraulic drilling jumbo for tunneling and cavern excavation of 20-211 m² cross sections, including face drilling, bolt hole drilling, and mechanized long-hole drilling. It has been designed with successful operations in mind being fast, accurate and user-friendly. Together with the iSURETM tunnel management program, intelligent iDATA control system, newly launched high frequency RD525 drills, robust booms and advanced drill string guides, it provides an excavation result of the highest quality with the lowest cost.

Refilling the tunnel base

Sandvik's role has not been limited to the excavation of the tunnel. Two QJ241 tracked jaw crushers have also been put to work crushing the excavated granite in order to provide a base for the road construction in the tunnel. Here the attributes of the QJ241 have been shown to its full. Although granite is a hard and notoriously difficult rock to crush, the QJ241 has dealt with the 600mm feed-size in order to produce a -250mm product. This is further fed into the 2nd QJ241 in order to produce a -40mm product for the tunnel refilling.

The QJ241 is the smallest compact tracked jaw crusher in the world leading series of Sandvik tracked crushers. This highly productive, yet self-propelled machine brings the leading features of the Sandvik jaw crusher ranges to places where operating room is limited, yet high performance demanded. Compact and mobile, the QJ241 utilizes a substantial 1000 x 650 mm / 40 x 26" jaw with hydraulically adjustable CSS and a reversible jaw for relieving blockages. It is the ideal solution for hard rock applications such as found on the Contract 6 tunnel rock.

Support in the field

One of the reasons why Sandvik equipment was chosen was due to the fact that Sandvik Hong Kong is able to provide full and proactive support from the very first day of operation. A full service and maintenance agreement was signed between Sandvik and the CRBC-CEC-Kaden JV as well as Sandvik providing all spare parts, lube and oil. "The excellent customer service (provided by Sandvik) is as important to us as the quality of the equipment, providing us with a one-stop-shop", so says Mr. Chow. "The work is due to last over 40 months and we know this will place a great strain on our equipment and people. But with support from Sandvik we know that our equipment will be kept operating at peak performance," Mr. Chow adds.

For further information, please contact:

Kenny Chen
Sandvik Hong Kong
Tel: +852 9328 0482
E-mail: kenny.chen@sandvik.com

Melissa Baker
Marketing Communications Manager
Sandvik Mobile Crushers and Screens
Tel. +44 1283 818164
E-mail: melissa.baker@sandvik.com