Materials for Civil and Construction Engineers (4th Edition)
4th Edition
ISBN: 9780134320533
Author: Michael S. Mamlouk, John P. Zaniewski
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 6.13QP
The water–cement ratio is important because it influences all of the desirable qualities of concrete.
a. Referring to Figure 5.10, which portion of water is used to calculate the water–cement ratio?
b. What is a typical water–cement ratio for normal strength concrete?
c. What is the water–cement ratio needed for hydration only when concrete is in the plastic state?
d. Why is the extra water necessary?
e. Briefly describe how super high strength concrete (fc′ = 15,000 psi) can be made.
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Concrete is strongest when subjected to:
O A) Tension
O B) Bending
O9 Torsion
O D) Compression
If a peak load of 250 kN was exerted on a 100 mm x 200 mm test cylinder, the
compressive strength of the concrete is:
OA) 28.6 MPa
O B) 35.2 MPa
O9 31.8 MPa
O D) 32.4 MPa
The approximate volume percentages of the principal components of a concrete
mixture are: 6%, 11%, 41%, 26%, 16%. Which of the following lists matches the
correct order of these main components? Start with the one at 6% and end with the
one at 16%.
O Air, Water, Coarse Aggregate, Fine Aggregate, Cement
O Water, Coarse Aggregate, Fine Aggregate, Cement, Air
O Air, Coarse Aggregate, Fine Aggregate, Water, Cement
O Air, Cement, Coarse Aggregate, Fine Aggregate, Water
Under ideal conditions, concrete should be batched and placed within after
mixing, when retarding admixtures are not used.
OA 90 minutes
O B) 1/2 hour
OC 4 hours
O D) 120 minutes
A concrete mix includes the following ingredients per cubic meter:
Cement%3D400 kg
Water=184 kg
No admixture
Table below shows possible alternatives mix ingredients. Indicate in the appropriate boxes in the
table what will happen in each case for the workability and the ultimate compressive strength as
increase, decrease or approximately the same.
What will happen?
Cement
Water
Admixture
(kg)
(kg)
Ultimate compressive
Workability
strength
400
225
None
449
184
None
Water
400
184
Reducer
Water
400
128
Reducer
400
184
Super
Plasticizer
400
184
Air Entrainer
400
184
Accelerator
DFocus
The water–cement ratio is important because it influences all of the desirable qualities of concrete.
a. Referring to Figure 6.10, which portion of water is used to calculate the water–cement ratio?b. What is a typical water–cement ratio for normal strength concrete?c.What is the water–cement ratio needed for hydration only when concrete is in the plastic state?d.Why is the extra water necessary?e.Briefly describe how super high strength concrete (fc′=15,000 psi) can be made.
Chapter 6 Solutions
Materials for Civil and Construction Engineers (4th Edition)
Ch. 6 - What ingredients are used for the production of...Ch. 6 - What is the role of gypsum in the production of...Ch. 6 - What is a typical value for the fineness of...Ch. 6 - What are the primary chemical reactions during the...Ch. 6 - Define the C-S-H phase of cement paste.Ch. 6 - What are the four main chemical compounds in...Ch. 6 - Prob. 6.7QPCh. 6 - Define a. interlayer hydration space b. capillary...Ch. 6 - Prob. 6.9QPCh. 6 - The following laboratory tests are performed: a....
Ch. 6 - What is a false set of portland cement? State one...Ch. 6 - The watercement ratio is important because it...Ch. 6 - Discuss the effect of watercement ratio on the...Ch. 6 - Draw a graph to show the general relationship...Ch. 6 - Students in the materials class prepared three...Ch. 6 - Students in the materials class prepared three...Ch. 6 - Two batches of cement mortar with properties as...Ch. 6 - What are the five primary types and functions of...Ch. 6 - Why isnt pozzolan used with Type III cement?Ch. 6 - What type of cement would you use in each of the...Ch. 6 - In order to evaluate the suitability of nonpotable...Ch. 6 - Three standard mortar cubes were made using...Ch. 6 - Four standard mortar cubes were made using...Ch. 6 - Discuss the problem of disposal of waste water...Ch. 6 - State five types of admixtures and discuss their...Ch. 6 - Prob. 6.27QPCh. 6 - Under what condition is an air-entraining agent...Ch. 6 - If a water reducer is added to the concrete mix...Ch. 6 - Prob. 6.30QPCh. 6 - A concrete mix includes the following ingredients...Ch. 6 - The results of an experiment to evaluate the...Ch. 6 - The results of a laboratory experiment to evaluate...Ch. 6 - Referring to Table P6.34, Mix No. 1 was designed...Ch. 6 - Two batches of concrete cylinders were made with...Ch. 6 - Two batches of concrete cylinders were made with...Ch. 6 - What is the source of fly ash? Why is fly ash...Ch. 6 - A materials engineer is working in a research...Ch. 6 - A materials engineer is working in a research...
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