August 1977 Table of Contents

PROBLEM CLINIC
Problem Clinic Superplasticizers for Easy Consolidation

The Problem Clinic item on page 232 of the April 1977 issue says that Portland Cement Association made a mix with 11.4-percent air content and a slump of 8.5 inches to get the mix to flow easily into forms and make it easy to consolidate. Couldn't we do t Read more

Problem Clinic Laitance Removal

Removing the laitance at the top of placements in a small dam is consuming an excessive amount of time. We sandblast the surface, but a considerable amount of concrete gets abraded off. Then we have a layer of both sand and concrete particles that have to Read more

Problem Clinic Roll-A-Bugs and Popouts

What is the probability of popouts due to stresses incurred by freezing and thawing in a slab of regular-aggregate concrete that has been roll-abugged prior to bull floating as compared with a slab of crushed stone or white rock concrete? Read more

Problem Clinic Safeguarding Alignment of Post-Tensioning Tendons

There is some chance that some post-tensioning tendons in a slab are misaligned. Could this be due to the impact of the concrete at the time it is placed? Read more

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