Rating System for the Concrete in Navigation Lock Monoliths. Repair, Evaluation, Maintenance, and Rehabilitation Research Program

摘要

The purpose of this report is to describe a proposed system for determining a condition index (CI) that numerically rates the condition of the concrete in a lock monolith on a scale of 0 to 100 by evaluating each concrete deficiency. The rating system described herein allows the CI to be determined by the use of a visual investigation with limited equipment. The rating is related primarily to structural integrity and secondarily to serviceability. The CI procedure was developed by assigning specific deduct values to defects which include the following distress categories: alignment, cracking (checking, D-cracking, pattern, horizontal, vertical and transverse, vertical and longitudinal, diagonal, random, and longitudinal floor), volume loss (abrasion, cavitation, honeycomb, pop-outs, scaling, spalling, and disintegration), steel deterioration (corrosion stains, reinforcing, prestressing, and armor), and leakage and deposits. The deduct values are subtracted from 100 to establish the CI. Primary deduct values were determined with the intent of obtaining a CI of zero when deterioration of a concrete monolith caused the safety of that monolith to become critical. Nominal deduct values were assigned for defects in serviceability. Deduct values for distress categories that tend to result in loss of concrete from the structure (volume), and thus effective weight and cross section, were assigned by making approximations concerning safety and assuming (a) all sections were cracked so that no tension or cohesion existed at the section and (b) the total force tending to produce sliding or total moment tending to produce overturning was constant. (SDW)