Seite - 703 - in Book of Full Papers - Symposium Hydro Engineering

2. THE EVOLUTION OF CONTEMPORARY PRACTICE 2.1 REFERENCEABLE STANDARD OF CARE There is no standard, per se, for rock anchoring in the U.S. However, the current governing document is “Recommendations for Prestressed Rock and Soil Anchors,” Fifth Edition, 2014, published by the Post-Tensioning Institute [4]. This document, like its predecessors, was developed by a Committee of industry specialists and practitioners, an equal blend of consultants, contractors, suppliers, and regulators/ clients (Table1). The previous four editions (1980, 1986, 1996 and 2004) were in fact preceded in 1974 by the “Tentative Recommendations” document for the Prestressed Concrete Institute which, as the breakdown of Table 2 clearly illustrates, was principally a marketing and sales tool whose goal was to present illustrated applications to expand sales volumes of prestressing steel. Table 1 Number and affiliations of ACI/PTI Prestressed Rock and Soil Anchor Committee members. ASPECT 1974 1980 1986 1996 2004 2014 Post-Tensioning Suppliers 6† 4* 4* 2* 3* 4 Anchor Contractors 2 2 3 3 3 3● Consultants 2 None 1 2 2 2 Owners/Regulators 1 2 1 3 3 3 Sponsor Organizations 1 None 0 1 1 2 TOTAL 12 8 9 11 12 14 * Including the same Chairman from DSI (Post-Tensioning Supplier). † Chairman from VSL (Post-Tensioning Supplier). ● Chairman from Schnabel Foundations (Specialty Contractor). Table 2 Number of pages of major sections of the PTI Recommendations. ASPECT 1974 1980 1986 1996 2004 2014 Materials 1 2 2 8 10 10 Site Investigation 0 1 1 1 2 2 Design 2 6 ½ 6 ½ 12+ Appendix on grout/ strand bond 13 13 Corrosion Protection 1 4 5 10 14 15 Construction 7 9 9 10 15 17 Stressing and Testing 1 6 8 17 18 19 Bibliography/References 0 1 1 1 ½ 4 3 (continues) 703