Elastic joint spanning waterstop element

Claim 1

A flexible, elastic, joint-spanning waterstop element designed to be locked into recesses formed on either side of a joint space in two opposed, spaced, sections of concrete and at the surfaces thereof, by hardenable fluid grout placed thereover, said waterstop element being in the form of a continuous length of flexible elastic strip material having in cross-section a width greater than its height and greater than the width of said joint space, said strip further in cross-section having a center portion for location in the joint space between said concrete sections and over which no grout is placed, said center portion being configured such that it will stretch laterally beyond the normal elastic ability of the material from which it is made, said strip further having in cross-section a pair of lateral web portions over which fluid hardenable grout is placed each extending outwardly from, and on opposite sides of, said center portion; each of said web portions in cross-section having upper and lower generally planar surfaces and terminal end surfaces remote from said center portion, said upper and lower generally planar surfaces forming an angle with said center portion at the point at which each meets said center portion, said lower planar surface of each web being substantially smooth, said upper planar surface of each of said web portions in cross-section having a first upstanding rib raised therefrom continuously extending along the longitudinal length of said strip and located generally between its terminal end surface and the point at which it meets said center section but spaced back a distance from such juncture point in the direction of said terminal end surface in order that no portion of the said upstanding rib is located in the said joint space when the waterstop element is positioned between said concrete sections and in order further that said rib will be fully embedded in the fluid grout placed thereover; said web portions of said strip further each having a plurality of preformed openings therethrough located between said first raised rib and said terminal end surfaces and a second upstanding rib raised therefrom also continuously extending along the longitudinal length of said strip and located between said openings and said terminal end surfaces; the said openings in each web portion connecting the said upper and lower surfaces of said web portions, all cross-wise dimensions of said openings being at least about 1/4 inch and said openings being spaced from one another along the longitudinal length of the strip a maximum distance of 1 to 2 inches.