Contact method (concrete construction)

Prefabricated bridge segment on a low loader. The elevations for the transmission of the shear forces ( male shear keys ) and the holes through which the tendons will later be guided are clearly visible .

The contact method (often also for short: Match Casting from the English term Match Casting Method ) is a process in the manufacture of precast concrete parts in which one side of an already completed part serves as formwork for the part of the row to be connected to it.

invention

The contact method was invented by the French engineer Jean Muller in 1954, who first applied the principle when building the Shelton Bridge, a small bridge in the New York area.

Usage and technical background

The contact method is mainly used in the construction of bridge segments, which are later strung together and prestressed with tendons . Here it is particularly important that the segments fit together very precisely. In order to avoid unwanted (and dangerous) voltage peaks, the joints should therefore be free of gaps or voids. The fact that with the contact method one segment is concreted against its neighboring segment ensures that the prefabricated parts match each other exactly during installation.

A shear-resistant connection in the joints is achieved by a kind of tongue and groove connection . For this purpose, a groove is embossed with the formwork of the prefabricated part. When concreting the next part against this groove, the appropriate tongue is formed. In English one speaks of male and female shear key , ie a male and a female “ key pair ” for the transmission of the shear forces.

Web links

Individual evidence

↑ Roland Niedermeier: Solid construction across the board: Festschrift for the 60th birthday of Univ.-Prof. Dr.-Ing. Konrad Zilch , Springer, 2005, ISBN 978-3-540-22541-6 , p. 78 f.
^ Daniel M. Tassin: Jean M. Muller: Bridge engineer . In: Precast / Prestressed Concrete Institute (Ed.): PCI Journal . Vol. 51, No. 2 , 2006, ISSN 0887-9672 , p. 88–101 (English, online [PDF; 2.2 MB ]).
↑ ^a ^b civcal.media.hku.hk - Match Casting ( English )

[Niedermeier-S78f-1] Roland Niedermeier: Solid construction across the board: Festschrift for the 60th birthday of Univ.-Prof. Dr.-Ing. Konrad Zilch , Springer, 2005, ISBN 978-3-540-22541-6 , p. 78 f.

[2] Daniel M. Tassin: Jean M. Muller: Bridge engineer . In: Precast / Prestressed Concrete Institute (Ed.): PCI Journal . Vol. 51, No. 2 , 2006, ISSN 0887-9672 , p. 88–101 (English, online [PDF; 2.2 MB ]).

[CIVCAL-3] vcal.media.hku.hk - Match Casting ( English )