Chapter 19 and 20 concrete quiz
3. Ultra high performance concretes utilize superplasticizers to reduce the water-cement ratio to less than
.2
Typical compressive strengths for structural lightweight concrete range from______
3000 psi to 5000 psi
What is the generic maximum temperature differential for mass concrete?
36 F
. For roller compacted concrete pavement applications, cement contents range from ____
400-600 pounds per cubic foot
. Insulating concrete is a lightweight concrete with an oven dry density of ____ of less
50 pounds per cubic foot
9. About _____ of ready mixed concrete has a 28 day specified compressive strength ranging from 3000 psi to 6000 psi.
90%
6. The time in which a specified strength for a high-early-strength concrete should be achieved may range from_____ to several days.
A FEW HOURS
7. High cementitious material contents, large dosages of admixtures, low water contents, and air entrainment all contribute to high-performance concrete being ______.
Difficult to finish
Current ASTM tests specifically for self-consolidating concrete test the flowing ability, the _____, and the dynamic and static stability.
passing ability
8. High performance concrete with low water to cement ratios can ______ to a level that does not allow alkali-silica reaction to occur.
self desiccate
2. High performance concrete has a very good resistance to carbonation due to it low permeability
true
The preplaced aggregate method of concrete construction reduces drying shrinkage
true
10. One benefit for using self-consolidating concrete is_____.
Its ability to be placed in congested areas
5. High performance blast resistant concrete often has a compressive strength exceeding_____ and contains steel fibers
14500 PSI
Previous concrete has a void concrete of approx. _______
15-35%
What is the maximum expected temperature rise of concrete moisture due to the heat of hydration of Type I Portland Cement?
16F per 100 pounds of concrete
. No slump concrete is defined as concrete with a consistency corresponding to a slump of ____ or less.
1/4"
The amount of color pigments added to a concrete mixture should not be no more than ____ of the weight of the cementitious material
10 %
1. Most high strength concrete applications are designed for compressive strengths of _____ or greater.
10000 psi
Of the following aggregates, which are used to produce high-density concrete?
Barite