Retaining walls are used widely to construct soil embankments, sound barriers, and highway dividers, as well as for other similar and dissimilar purposes.
A retaining wall of a type in widespread use is made from concrete modules stacked in multiple courses. The modules are spaced laterally from one another in each course so that modules of each intermediate course are straddled by modules of the next course above and by modules of the next course below.
Since the modules are stacked so as to provide spaces therewithin and therebetween for plantable earth, a retaining wall of the type noted above is plantable. Vegetation planted in those spaces decorates the retaining wall and may help to anchor the modules.
Retaining walls of the type noted above and concrete modules therefor are exemplified in European Patent Application (Publication) No. 13,535, Steiner U.S. Pat. No. 4,379,659 and U.S. Pat. No. 4,521,138, Zeidman U.S. Pat. No. 5,072,566, Rausch U.S. Pat. No. 5,108,231, and Winkler et al. U.S. Pat. No. 5,177,925.
As exemplified in Swiss Patent No. 587,390 and corresponding German Published Patent Application (Offenlegungsschrift) No. 2,537,408, it is known for such a concrete module to have an open-topped, open-backed, trough-like configuration, which is defined by unitary front, lateral, and bottom walls. As illustrated and described therein, the front wall extends above the lateral walls and beyond the lateral walls on each side of the module, and the bottom wall is recessed upwardly from the lower edges of the front and lateral walls.
As a practical matter, the maximum height for a retaining wall built with such concrete modules, as described in the preceding paragraph, is limited by the columnar strength of the lateral walls of the modules. A maximum height of seven meters therefor is suggested by Winkler et al. U.S. Pat. No. 5,177,925, in column 1, lines 55 et seq. Such height limitations will be substantially more severe with curved (i.e., concave or convex) retaining walls.
As exemplified in Gavin U.S. Pat. No. 5,066,169, it is known to anchor a geogrid to concrete modules for a retaining wall, via retainer bars coacting with the geogrid and with integral bars on the modules.
Concrete modules of related interest, some having means for anchoring geogrids thereto, are exemplified in Broadbent U.S. Pat. No. 4,470,728, Giardini U.S. Pat. No. 4,671,706, Forsberg U.S. Pat. No. 4,914,876, Miner U.S. Pat. No. 4,936,714, Rossi U.S. Pat. No. 4,964,761, and Janopaul, Jr., U.S. Pat. No. 5,044,834.
Retaining walls of related interest, some employing geogrids, are exemplified in Broms et al. U.S. Pat. No. 3,925,994, Hilfilker U.S. Pat. No. 4,616,959, O'Neill U.S. Pat. No. 4,684,294, Brown U.S. Pat. No. 4,824,293, Wilson et al. U.S. Pat. No. 5,028,172, Risi et al. U.S. Pat. No. 5,064,313, and Strassil U.S. Pat. No. 5,108,232.