碩士 / 國立交通大學 / 土木工程學系研究所 / 85 / Based upon the exhausted usage of river sand gradually in Taiwan and tremendou
s coverage of offshore sand because of Taiwan geography condition. It is impor
tant to find out usable materials to replace river sand. The benefits to utili
ze washed offshore sand to be fine aggregates are well particle shape, less di
fference compressive strength at the same W/C ratio, and almost same amounts o
f cement with fineness modulus over 1.1 compared with river sand. The advantag
es of slag are excellent subsequent strength development, low heat-liberation,
high durability and chemical resistibility of concrete. As these reasons, the
purpose of the paper is to use offshore sand as fine aggregates and replace p
art of cement with slag to study the properties of engineering.This research u
sed the washed offshore sand from Taoyuan to be fine aggregates and the slag p
roduced by Chinese Steel Company as materials. By fixing the S/A ratio as 0.4
and the slump as 15 cm, we changed the W/C ratio from 0.5 to 0.8 and the subst
itution of slag from 0% to 60%. We found out that the amount of water per cubi
c meter decreased after adding slag, that is, at the same W/C ratio, more subs
titution of slag, less usage of water. On the other side, at the same substitu
tion of slag, the one with higher W/C ratio, the longer hydrated time was need
ed. So, we should prolong the age of concrete for estimating its compressive s
trength. As strength was concerned, the optimum substitution of slag was incre
ased as the W/C ratio increased. The maximum strength of each W/C ratio is : t
he substitution is 20% while W/C ratio is 0.5; the substitution is 30% while W
/C ratio is 0.6 and 0.7; the substitution is 40% while W/C ratio is 0.8. Also,
we got the same results in analysis the economic benefits. However, except th
e substitution as 60%, the larger rate of strength increased with higher W/C r
atio and more substitution of slag. The properties of the substitution as 60%
were poor within different kinds of W/C ratio and different ages. By the way,
we got longer setting time and higher resistibility of sulfate attack on concr
ete when adding slag.
| Identifer | oai:union.ndltd.org:TW/085NCTU0015010 |
| Date | January 1997 |
| Creators | Chien, Hung-Lin, 簡宏霖 |
| Contributors | Yi-Yu Kuo, 郭一羽, --- |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 62 |
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