16-17485 - Laserfiche WebLink

Browse Search

Report of Concrete Slab Evaluation . RE&A Project No. 2825-15-023-SE-A Existin�TKM Aviation Han�ar June 27 2017 Summary of Laboratory Testing • A representative 6-inch core, 6CORE-6, was selected for petrographic analyses (ASTM C856), to possibly determine the cause of the distress and evaluate general concrete composition and characteristics. The sample 6CORE-6 exhibited two intersecting cracks, extending through the length of the core. • The three 3-inch diameter concrete cores from the site were submitted for compressive strength testing. • A representative soil sample obtained from the clayey sand layer was selected for Single Sieve Analyses (ASTM D1140), Natural Moisture Content (ASTM D2216), and Atterberg Limit Testing(ASTM D4318). • The petrographic analysis was performed by CTL Group and the results were presented in their "Report of Petrographic Examination", dated June 9, 2017. The report states that the concrete"e�ibits generally good physical properties evidenced by relatively hard and dense paste", "well consolidated without large voids", and does not show any evidence of ' deleterious reactions involving aggregates and/or paste constituents. The report also provided that the estimates for water-cement ratio of 0.45 to 0.55 (mix design is 0.55), entrapped air content of less than 1% and 15 to 25% of residual fly ash particles, and that two layers of steel wire mesh are identified to be embedded between depths of 3.1 to 3.4 inches and 3.9 to 4.3 inches. Based on the examination of the core,the report states that the cracks were apparently present before the epo� coating was applied. CTL finally I summarizes that cracks are a result of plastic shrinkage, a possible outcome of rapid � evaporation of moisture from concrete surface due to high temperature, low humidity and high wind speed. • The concrete compressive strength tests were performed by Faullrner Engineering Services, � Inc. The results indicate that the compressive strength of the concrete was the in the range of 2,930 to 5,360 psi,with an average of 4,300 psi. • The laboratory tests on the representative soil sample collected from within initial 1 to 1.5 feet indicate that the fill soils constitute clayey sands with 29% clay with a liquid limit of 28 and plasticity index of 14. 5