Answer question 2 Q1) Define the C-S-H phase of cement paste.Q2) Discuss the effect of water-cement ratio on the quality ofhardened concrete. Explain why this effect happens.Q3) In order to evaluate the suitability of nonpotable wateravailable at the job site for mixing concrete, six standard mortarcubes were made using that water and six others using potablewater. The cubes were tested for compressive strength after 7days of curing and produced the loads to failure (in pounds)shown in Table:Cubes Made with Nonpotable Water Cubes Made with Potable Water14,53016,53016,82017,92015,69018,82016,72015,82014,16016,10015,87014,380Based on these results only, would you accept that water formixing concrete according to ASTM C94?

To discuss:- Effect of water cement ratio on quality of hardened concrete and reason for this effect…

Answered: Q2) Discuss the effect of water-cement…

Engineering

Civil Engineering

Q2) Discuss the effect of water-cement ratio on the quality of hardened concrete. Explain why this effect happens.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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7.43 Three batches of concrete were prepared using the same materials and ingre- dients, except that they have water-cement ratios of 0.50, 0.55, and 0.60, respectively. The following tests were performed on specimens made of the three batches: Compressive strength test on 100 mm × 200 mm cylinders · Center-point flexure test on 100 mm × 100 mm × 300 mm beams Split tension test on 150 mm × 300 mm cylinders Three replicates were tested for each test. Table P7.43 shows the average fail- ure loads for the three replicates of each case. It is required to do the following: a. Complete Table P7.43 b. Using an Excel sheet, plot the relationships between water-cement ratio and compressive strength, modulus of rupture, and tensile strength on the same graph. Label all axes and curves. c. Comment on the effect of water-cement ratio on the compressive strength, modulus of rupture, and tensile strength. Questions and Problems 351 TABLE P7.43 w/c Ratio Compressive Strength Test Flexure Test Split…