Over deze norm
1.1 This practice covers procedures for surveying concrete bridge decks by sounding to determine delaminations in the concrete. It is not intended that the procedures described herein are to be used on bridge decks that have been overlaid with bituminous mixtures. The procedures may be used on bridge decks that have been overlaid with portland cement concrete mixtures; however, areas indicated to be delaminated may have a lack of bond between the overlay and the underlying bridge deck (Note 1).
Note 1—The influence of variable field conditions such as traffic noise, vibration, moisture content of the concrete, and the like, are not completely known and additional investigation may be needed. It is generally agreed that the practice should not be used on frozen concrete.
1.2 The following three procedures are covered in this practice:
1.2.1 Procedure A, Electro-Mechanical Sounding Device—This procedure uses an electric powered tapping device, sonic receiver, and recorder mounted on a cart. The cart is pushed across the bridge deck and delaminations are recorded on the recorder.
1.2.2 Procedure B, Chain Drag—This procedure consists of dragging a chain over the bridge deck surface. The detection of delaminations is accomplished by the operator noting dull or hollow sounds. Tapping the bridge deck surface with a steel rod or hammer may be substituted for the chain drag.
1.2.3 Procedure C, Rotary Percussion —This procedure consists of rolling a dual-wheel, multi-toothed apparatus attached to an extension pole over the bridge deck surface. The percussive force caused by the tapping wheels will create either a dull or hollow sound indicating any delamination.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
|Engelse titel||Standard Practice for Measuring Delaminations in Concrete Bridge Decks by Sounding|