An experimental study was conducted to characterize Portland cement concrete (PCC), to
detect deterioration induced by freeze/thaw and alkali-silica reaction, and to detect
chloride presence in PCC using ultrasonic waves. The experimental program was initiated
to investigate the effect of water to cement (w/c) ratio, aggregate type, and air
entrainn1ent on measured ultrasonic wave velocity and signal energy. Three w/c ratios
(0.35, 0.45, and 0.55) were evaluated. Two aggregate types, quartzite and limestone,
were included in the PCC mixes separately. Mixes were prepared as non-air entrained and
air entrained. Thus, a total of twelve batches were prepared to evaluate PCC using
ultrasonic waves at two frequencies, 54 and 340 kHz.
The experimental program to investigate freeze/thaw (FT) damage included the effect of
curing time, w/c ratio, and aggregate type. The effect of curing time was investigated by
exposing PCC specimens cured for 3 and 7 days to FT. Two w/c ratios were considered,
0.45 and 0.55. The effect of aggregate on detecting FT damage was investigated using
two types of crushed stone aggregate, quartzite and limestone. Alkali-silica reaction (ASR) damage was investigated uSIng two w/c ratios, 0.35 and 0.45. Embedded
composite strain gages were used to monitor the ASR deleterious deterioration. High
alkali cement and active silica aggregate were used to produce ASR.
next to an author's name indicates that all files or directories associated with their ETD are accessible from the Virginia Tech campus network only.
![[VT]](http://scholar.lib.vt.edu/images/ETD-db/restricted.gif)
