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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Chapter 6, Problem 6.39QP
A materials engineer is working in a research project to evaluate the effect of one type of admixture on the compressive strength of concrete. She tested 10 mortar cubes made without admixture and 10 others with admixture after 28 days of curing. The compressive strengths of cubes without admixture were 25.1, 24.4, 25.8, 25.2, 23.9, 24.7, 24.3, 26.0, 23.8, and 24.6 MPa. The compressive strengths of cubes with admixture were 25.3, 26.8, 26.5, 24.5, 27.2, 24.8, 24.1, 25.9, 25.3, and 25.0 MPa. Using the statistical t-test, does this admixture show an increase in the compressive strength of the cement mortar at a level of significance of 0.05?
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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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