Joint for pre-cast concrete twin-leaf arch sections

A method of joining pre-cast concrete twin-leaf arch sections together comprising:

• providing pre-cast concrete twin-leaf arch sections each having a central portion and two side surfaces separated by a longitudinal dimension;
• abutting a crown section end of arch section against a crown section end of an adjacent arch section;
• providing self-aligning and locking means on said crown section ends of said arch sections;
• mechanically locking said one arch section to said adjacent arch section during said abutting step;
• providing two further pre-cast concrete twin-leaf arch sections each having a central portion and two side surfaces separated by a longitudinal dimension;
• mechanically locking said mechanically locked arch sections to the two further locked arch sections located longitudinally adjacent to said mechanical locked arch sections;
• and
• placing cast-in-place concrete on the mechanical locked arch sections adjacent to the mechanical lock formed during said mechanical locking step.

A joint for pre-cast concrete twin-leaf arches comprising:

• two adjacent pre-cast concrete twin-leaf arch sections, each section including a crown area having an end and a central portion, and two side surfaces separated by a longitudinal dimension;
• self-aligning means on the ends of said arch sections for mechanically joining one arch portion adjacent to the crown area of said one arch section to a second arch portion adjacent to the crown area of said second arch section and for automatically orienting each arch section with respect to the other arch section as said arch sections are initially brought into contact with each other adjacent to the crown section of each arch sections;
• step sections on opposite sides of said central portions of said arch sections for receiving cast-in-plate concrete;
• two further adjacent pre-cast concrete twin-leaf arch sections which include two side surfaces separated by a longitudinal dimension, a crown area, and a further self-aligning means mechanically joining one of said two further adjacent arch sections to the other arch section of said two further adjacent arch sections, said two further adjacent pre-cast concrete twin-leaf arch sections being longitudinal to said two adjacent pre-cast concrete twin-leaf arch sections;
• and
• connecting means in the crown areas of said pre-cast twin-leaf arch sections connecting said two adjacent pre-cast concrete twin-leaf arch sections to said two further adjacent pre-cast concrete twin-leaf arch sections.

A joint for pre-cast concrete twin-leaf arches comprising:

• two adjacent pre-cast concrete twin-leaf arch sections, each section including a crown area having a top surface, a bottom surface and two side surfaces;
• initial contact areas in the crown area on said arch sections that allow a controlled transmission of abutting forces;
• and
• self-aligning and locking means located substantially centrally between two side surfaces in the crown area on said arch sections for mechanically joining one arch section to the second arch section as said arch sections are initially brought into contact with each other and located spaced from said surfaces, and step sections on each arch section adjacent to said self-aligning and locking means.