Ariston Pacific, Inc. 5/9/2016 - Laserfiche WebLink

I 1 in that line shall be cored and tested. Cores shall avoid all prestressing strands, steel I 2 reinforcing bars and interior voids. 3 4 For prestressed concrete slab girders, a test shall consist of four cores measuring 3 5 inches in diameter by 6 inches in length (for slabs) or by the thickness of the web (for 6 ribbed and double tee sections). Two cores shall be taken from each side of the girder 7 with one on each side of the girder span midpoint, at locations accepted by the 8 Engineer. The core locations for prestressed concrete ribbed and double tee sections 1 9 shall be immediately beneath the top flange. 10 11 For prestressed concrete tub girders, a test shall consist of four cores measuring 3 12 inches in diameter by the thickness of the web. Two cores shall be taken from each 13 web, approximately 3 feet to the left and to the right of the center of the girder span. 14 I 15 For all other prestressed concrete girders, a test shall consist of three cores measuring 16 3 inches in diameter by the thickness of the web and shall be removed from just below 17 the top flange; one at the midpoint of the girder's length and the other two approximately I 18 3 feet to the left and approximately 3 feet to the right. 19 20 The cores shall be taken in accordance with AASHTO T 24 and shall be tested in 21 accordance with WSDOT FOP for AASHTO T 22. The Engineer may accept the girder if I22 the average compressive strength of all test cores from the girder are at least 85 23 percent of the specified compressive strength with no one core less than 75 percent of 24 specified compressive strength. I 25 26 If there are more than four cored holes in a girder, the prestressing reinforcement shall 27 not be released until the holes are patched and the patch material has attained a I 28 minimum compressive strength equal to the required release compressive strength. 29 30 All cored holes shall be patched and cured prior to shipment of the girder. The girder 31 shall not be shipped until tests show the patch material has attained a minimum 32 compressive strength of 4,000 psi. 33 I 34 If the annual plant approval includes procedures for patching cored holes, the cored 35 holes shall be patched in accordance with this procedure. Otherwise, the Contractor 36 shall submit a core hole patching procedure as a Type 2 Working Drawing. 37 I 38 6-02.3(25)F Prestress Release 39 The second and third paragraphs are revised to read: 40 1 41 All strands shall be released in a way that will minimize eccentricity of the prestressing 42 force about the centerline of the girder. This release shall not occur until tests show 43 each girder has reached the minimum compressive strength required by the Plans. I 44 45 The Contractor may request permission to release the prestressing reinforcement at a 46 minimum concrete compressive strength less than specified in the Plans. This request I 47 shall be submitted as a Type 2E Working Drawing and shall be accompanied with 48 calculations showing the adequacy of the proposed release concrete compressive 49 strength and any effects on girder camber. The calculated release strength shall meet 50 the requirements outlined in the WSDOT Bridge Design Manual LRFD (M23-50) for 51 tension and compression at release. 52 1 I AMENDMENTS TO THE 2014 STANDARD SPECIFICATIONS BOOK Revised: 8/3/15