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tMr. Clyde Ellis , July 1 , 2003 , Page 3 <br /> ' � a ❑ KimleyHorn <br /> and Associates , Inc . <br /> • 462 - 13 Protection of Post-Tensioning Anchorages : Fill <br /> anchorage pourbacks using epoxy grout and seal with an <br /> elastomeric coating . <br /> ' Question #2 Sheets A- 10 and A- 11 call for a 3 " diameter PVC sleeve for <br /> transverse post-tensioning cables . Should this be changed to <br /> galvanized corrugated metal duct or plastic corrugated duct for <br /> ' better corrosion resistance? <br /> Response #2 The PVC sleeves for post-tensioning as shown in the plans were <br /> designed in accordance with FDOT Standard Specifications for <br /> Road and Bridge Construction ( 1991 ) with 1994 Supplemental <br /> Specifications , and the 1987 FDOT Structures Design Guidelines <br /> ' (through Revision "H") . Section 450 of the 1994 Supplemental <br /> Specifications (as well as the current version of the Standard <br /> Specifications) allows for the use of alternative materials if they <br /> meet a list of specified requirements . Based on current FDOT <br /> policy, it would appear that plastic corrugated duct would be an <br /> acceptable alternative to the PVC ducts shown in the plans . <br /> Galvanized corrugated metal duct would not be acceptable . <br /> Question #3 Sheet A- 10 describes the pourback material for the post-tension <br /> anchors to be non-shrink metallic grout. Should this material be <br /> epoxy grout? <br /> Response #3 The non-shrink non-metallic grout for filling of post-tensioning <br /> blockouts as indicated in the plans was specified in accordance <br /> with FDOT Standard Specifications for Road and Bridge <br /> Construction ( 1991 ) with 1994 Supplemental Specifications . <br /> Based on current FDOT policy, an epoxy grout product listed in <br /> the FDOT Qualified Products List (QPL) would be an acceptable <br /> alternative to the non-shrink non-metallic grout specified in the <br /> plans . <br /> Question #4 Sheet A-3 (post-tension cables) describes each tendon to have 3 <br /> strands with 0 . 6" diameter prestressing steel , Grade 270 . The <br /> plans call for 9 tendons across the deck. Will 7 tendons with 4 <br /> strands be allowed as long as the stress across the deck is 150 psi <br /> after losses? <br /> ' Response #4 The slab unit details in the plans are based on 9 post-tensioning <br /> ducts at 3 ' -0" on center with 3 strands per duct (27 strands total) . <br /> ' The proposed alternative to use 7 post-tensioning ducts with 4 <br /> strands per duct (28 strands total) would be an acceptable <br /> ' GA47035008Tonstruction Phase\Wp\VSLOI .doc <br />