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Maurer designed Expansion Joints for the Hong Kong-Zhuhai-Macau-Bridge

ZHUHAI/CHINA, April 26, 2017 – Presently, the 35 km long Hong Kong-Zhuhai-Macao Bridge (HZMB) is being constructed over the Pearl River Delta. One of many technical challenges is the Jianghai Bridge, a cable stayed bridge of 700 m main span. Maurer designed expansion joints that could be inserted into the prefabricated recesses in the end steel girder and connected to the bridge deck.

Since 2009 the HZMB is under construction and scheduled to be opened for traffic in the autumn of 2017. The steel bridge segments were prefabricated in a factory on land, in order to minimize steel works in situ to the extent possible. This also applies for the Jianghai cable stayed bridge which spans the main shipping lane.
While the HZMB in general consists of prefabricated segments of a length of 110 m, the Jianghai Bridge comprises field lengths of up to 258 m, which called for correspondingly large expansion joints.
In order to anchor the expansion joints into the steel bridge segments, at the front ends of the steel end girder openings had to be designed for the purpose of accommodating the support beams of the expansion joints.

Exactly equal gaps between the lamellas demonstrate the exactness of the control system of the sliding lamella expansion joint.

Maurer specifically designed expansion joints for the Jianghai Bridge. Exactly equal gaps between the lamellas demonstrate the exactness of the control system of the sliding lamella expansion joint. | Photo: Maurer

Preparing the Steel to Steel Connnection

For the Jianghai Bridge, Maurer, a specialist in mechanical engineering and steel construction, designed large expansion joints that were already completely prepared for the steel to steel connection into the bridge deck. In other words, the support beams of the expansion joints not only had to fit into the openings of the steel end girder, but they had to be inserted in one go from the front. The standard procedure of lowering of the expansion joints from above into a block-out was not possible. So for this bridge Maurer designed an expansion joint for a steel connection, which allowed the expansion joint to be inserted in one go.

The new sliding-lamella expansion joints were inserted at the main segments of the Jianghai cable stayed bridge.

The new sliding-lamella expansion joints were inserted at the main
segments of the Jianghai cable stayed bridge. | Photo: Maurer

The bars of the expansion joint were inserted in a “tilted” manner into one end of the bridge deck, then lowered into horizontal position, and finally inserted horizontally into the opposite openings of the adjacent bridge deck. Then, the supports just had to be welded to their respective steel deck. This process took 2-3 days, which for an expansion joint of this size is rather fast.

Installing the Expansion Joints at Jianghai Bridge

In the autumn of 2016, each four expansion joints of type DS1760 and type DS1200 were installed at the Jianghai Bridge, that is, expansion joints with a displacement capacity of 1,760 mm and 1,200 mm, respectively. Each of the expansion joints has a width of 16.3 m, weighing around 36 tons. They bridge the structural gaps of the 33 m wide bridge in pairs.

The installation of the 8 expansion joints took 20 days. With standard design, that is, skew support beams, the installation time would have taken at least twice this long.

With the control system of the lamella gaps it is irrelevant whether the movement of the bridge is being caused by temperature, wind, or later by traffic. This is a precondition of freedom of maintenance as well as long service life. bi

Read about Maurer's specifically developed earthquake proof pendulum bearings for Taro-Bridge.

The new design of the control system of the sliding lamella expansion joints.

The new design of the control system of the sliding lamella expansion joints. | Photo: Maurer