United States Department of Transportation
i
Design of ultra high performance concrete as an overlay in pavements and bridge decks.
-
2014-08-01
[PDF-4.65 MB]
Details:
-
Creators:
-
Corporate Creators:
-
Corporate Contributors:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
Corporate Publisher:
-
Abstract:The main objective of this research was to develop ultra-high performance concrete (UHPC) as a reliable, economic, low carbon foot
print and durable concrete overlay material that can offer shorter traffic closures due to faster construction. The UHPC was optimized
using supplementary cementitious materials (SCMs), proper combinations of aggregates, and adequate selection of fiber types and
contents. Three types of SCMs, including silica fume, Class C and F fly ash, and ground granulated blast-furnace slag (GGBS) were
used to optimize cement paste with high packing density. The optimized pastes were then used to produce UHPC materials with
various contents of fine aggregates and fibers to prove the feasibility of using the UHPC for bonded overlay. The optimized materials
were evaluated for workability, rheology, mechanical properties, and shrinkage, as well as their performance was compared to the
reference UHPC. In addition, the robustness of the optimized UHPC mixtures to variations of the mixing and curing temperatures was
also examined. Bond behavior and the effect of overlay thickness of the developed UHPC materials were also investigated in this
study.
The experimental study reported herein proved that the optimized UHPC mixtures can develop comparable performance to the
commercially available UHPC proportioned with 100% silica sand and 25% silica fume replacement, which was used as the reference
UHPC. Given the mix design of the reference UHPC, the UHPC mixtures developed in this study could be more environmental
friendly and cost-effective overlay materials compared to the reference UHPC. It is important to note that the optimized UHPC
materials can develop adequate mechanical properties without any accelerated curing or special treatment, which contributes to a
reduction of overall construction cost of the overlay. The developed UHPC mixtures had equal to or lower drying shrinkage than the
reference UHPC.
The bond strength between the substrate concrete and the UHPC overlay was shown to be greater than that of the substrate concrete,
and the use of the UHPC overlay led to significant increase in flexural strength and toughness over the monolithic beam cast with
conventional concrete, regardless of the overlay thickness. These results indicate the feasibility of using the UHPC as a bonded
overlay.
-
Format:
-
Funding:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type:
