Another thing to remember in connection with concrete is that you are not allowed very much freedom for errors in either measurements or location. Once you have a solid mass of concrete set in place, it is going to stay there. You have a difficult job ahead of you if you try to remedy a mistake. Make very sure, before you fill the form, that everything is where and how you want it.
There are numerous rules regarding the proper mixing, handling, and finishing of concrete, but the essential one concerns the amount of water to use. The less water in the mix, the less the finished job will shrink. The less water used, the harder and more enduring the job after it has set.
The amateur concrete worker is annoyed with two desires. One is to use enough water to have the concrete nice and soft and easy to push around. You have been warned against that. The second is to take off the wooden forms too early, to see what the job looks like. That is really fatal. If the forms are stripped off too soon, while the concrete is still green, two things are likely to happen you are almost sure to break off corners or edges, and you are likely to cause a major crack or defect in the body of the work. An excellent rule is to wait until you are sure the concrete is properly hardened, and then wait another day before removing the forms.
Questions:
1. What would be the title for the selection?
______________ ______________ _______________ ______________ _____________
______________ ______________ _______________ ______________ _____________
2. What does the essential rule concern?
______________ ______________ _______________ ______________ _____________
______________ ______________ _______________ ______________ _____________
3. What is one of the desires the amateur must resist?
______________ ______________ _______________ ______________ _____________
______________ ______________ _______________ ______________ _____________
4. Which of the following qualities is not essential in someone who works with concrete: carefulness, diligence, patience, or self-control?
______________ ______________ _______________ ______________ _____________
______________ ______________ _______________ ______________ _____________
5. What does the author mean by saying the concrete is green?
______________ ______________ _______________ ______________ _____________
______________ ______________ _______________ ______________ _____________
Unit 4
S1. Rules for Working with Concrete.
S2. The amount of water to use.
S3. To use too much water. / To take off the wooden from too early.
S4. Diligence.
S5. Not dried out. / Not dry enough.
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