Appendix B

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Figure B1. Photographs of typical area of each section (Newark, DE).

(a) Control section 1 (C1)

(b) Test section 1 (TS1)

(c) Test section 2 (TS2)

(d) Control section 2 (C2)

(e) Control section 3 (C3)

(f) Control section 4 (C4)

(g) Test section 3 (TS3)

(h) Test section 4 (TS4)

(i) Control section 5 (C5)

Petrographic Report for Newark, DE, 1997

Sections from each of the cores were cut and lapped. These sections were then soaked overnight, dried, and the entire lapped surface was traversed under a stereo microscope. The lapped surface was divided into five or more traverses and examined at magnifications of 10 to 30 times. All instances of cracks, alkali-silica gel, and deteriorated or reacted aggregate particles were counted.

Core 97C1A: the core is poorly and nonuniformly air-entrained, with an estimated air content of 4.5 percent. Distress to the wearing surface appears limited to small popouts over fine aggregate particles. The core is moderately severely distressed. One major crack bisects the core into top and bottom halves. Additionally, 40 microcracks and 27 instances of alkali-silica gel were counted. Three coarse aggregate particles appear to have reacted slightly; 24 fine aggregate particles were distressed or had reacted.

Core 97C5A: the core is poorly and nonuniformly air-entrained with an estimated air content of 5 percent. Distress to the wearing surface appears limited to small popouts over fine aggregate particles. The core is moderately severely distressed. One major crack bisects the core into top and bottom halves. Thirty-four other microcracks were counted, and 31 occurrences of alkalisilica gel. Three coarse aggregate particles appear to have reacted slightly. Twenty-seven fine aggregate particles are distressed or have reacted.

Core 97T51A: the core is poorly and nonuniformly air-entrained with an estimated air content of 4 percent. Distress to the wearing surface appears limited to small popouts over fine aggregate particles. The core is severely distressed. Eighty-seven cracks were counted, along with 42 occurrences of alkali-silica gel. Thirty-one reacted or distressed fine aggregate particles were counted.

Core 97T52B: the core is marginally air-entrained with an estimated air content of 5 percent. Distress to the wearing surface appears limited to small popouts over fine aggregate particles. The core is moderately severely distressed. Forty-three cracks and 33 instances of alkali-silica gel were detected. Twenty-nine reacted or distressed fine aggregate particles were detected.

Core 97T53B: the core is well air-entrained with an estimated air content of 6.5 percent. Distress to the wearing surface appears limited to small popouts over fine aggregate particles. Distress is relatively minor. Seventeen cracks were counted, and 25 instances of alkali-silica gel. Twentythree fine aggregate particles had reacted or were distressed.

Core 97T54B: the core is poorly air-entrained with an estimated air content of 3.5 percent. Distress to the wearing surface is apparently limited to small popouts over fine aggregate particles. Distress is minor. Eight cracks and 13 occurrences of alkali-silica gel were counted. Thirty-one fine aggregate particles had reacted or were distressed.

Distress is relatively severe in all but the last two cores. We do not have sufficient information to interpret the possible reason, since all were treated with lithium compounds, but we have not been told what differences there were.

Petrographic Report for Newark, DE, 1998

Sections from each of the cores were cut and lapped. These sections were then soaked overnight, dried, and the entire lapped surface was traversed under a stereo microscope. Each lapped surface was divided into five or more traverses areas and examined at magnifications of 10 to 30 times. All instances of cracks, alkali-silica gel, and deteriorated or reacted aggregate particles were counted.

Core 98-C1-A: the core is severely distressed. The wearing surface is grooved and worn. Fine aggregate particles on the wearing surface are frequently exposed, occasionally in popouts. Seventy-seven microcracks, one large crack, and 49 instances of alkali-silica gel were counted. Thirty-nine reacted or distressed fine aggregate particles were counted. The core is air-entrained with an estimated air content of 6.5 percent.

Core 98-C5-B: the core is severely distressed. The wearing surface is grooved and worn. Fine aggregate particles on the wearing surface are frequently exposed, occasionally in popouts. Fiftyseven microcracks and 79 instances of alkali-silica gel were counted. Forty-two fine aggregate particles showed evidence of distress or reaction. The core is air-entrained with an estimated air content of 6 percent.

Core 98-TS1-A: the core is severely distressed. The wearing surface is grooved and worn, with fine and coarse aggregate particles partially exposed. Fine aggregate particles are occasionally exposed in popouts. Two major cracks and fifty microcracks were counted. Sixty-one instances of alkali-silica gel and 38 reacted or distressed fine aggregate particles were counted. The core is air-entrained with an estimated air content of 5.5 percent.

Core 98-TS-2B: the core is severely distressed. The grooved wearing surface is severely worn, exposing fine and coarse aggregate particles. Fine aggregate particles are frequently exposed in popouts. One major and 64 microcracks were detected. Fifty-eight instances of alkali-silica gel and 23 reacted or distressed fine aggregate particles were counted. The core is air-entrained with an estimated air content of 7.5 percent.

Core 98-TS-3A: the core is slightly to moderately distressed. The grooved wearing surface is moderately worn with both fine and coarse aggregate particles exposed on it, but with few identifiable popouts. Twenty-five microcracks and 43 instances of alkali-silica gel were counted. Fifteen fine aggregate particles had reacted or showed distress. The core is highly air entrained with an estimated air content of 8.5 percent.

Core 98-TS-4B: the core is slightly distressed. The grooved wearing surface is severely worn with no other distinct evidence of distress. Fourteen microcracks and 44 instances of alkali-silica gel were detected. Fifteen fine aggregate particles showed evidence of distress or reaction. The core is air entrained with an estimated air content of 7.5 percent.