This system is popular mainly in cold countries, where the dilatation problems given by the temperatures are lower. The tensions of the different materials: cement, frame of the dock leveller, finish of the pavement around the dock leveller, often results in fractures of the pavement. To combat this, the type with "L" frame has been created to solve some of the problems, but with much higher costs.
Three reinforced perimetrical walls are built, on the rim of which a rebate 150 mm wide and 100 mm high is formed. Into the rebate 20 mm diam. rods are fitted - to which the frame of the dock leveller shall be welded. Once the dock leveller is installed, the pavement is completed around the whole perimeter, however the dock leveller will be dirtied by cement and there is the risk of fractures to the pavement.
In these pits "C" type "suspended" dock levellers are installed, before the "wet trades" are finished. The dock levellers are dirtied with cement. Risk of fractures of the pavement.
The pit for "L" type dock levellers was conceived to avoid frequent fractures of the pavement that very often occur with the "C" system. It is made by a heavy reversed 80x80x8 mm "L" on the whole perimeter, strongly bracketed, with a plate 40 x 10 welded on the sides and a 20 x 10 on the head, on which the reversed "L" frame of the dock leveller is welded. The system is expensive but allows for pouring the pavement in once and for installing the dock levellers at the end of the "wet trades".