February 1989 Table of Contents

Features No Downtime Allowed

To repair the concrete structure supporting three nitric acid tanks at a chemical fertilizer plant, this contractor planned three 12- to 14-day shutdowns. But then fertilizer demand skyrocketed and the owner decided not to take the tanks out of service. To meet these changing needs, the contractor had to devise an on-the-run repair. Read more

Features Do It Right the First Time

Too often, designers mistakenly equate concrete durability with compressive strength. But the American Concrete Institute Committee 201, in its "Guide to Durable Concrete," defines durability of concrete as its ability to resist weathering, chemical attack, abrasion, or any other process of deterioration. Concrete isn't durable if poor quality or improper materials are used to produce it. Read more

Features Using Admixtures Successfully

Admixtures have long been used to enhance concrete performance. In choosing an admixture, the first step is to set goals that define what you want to accomplish. Read more

Features Use Breakeven Analysis to Choose the Lowest Cost Forming Option

Controlling job forming cost should start with an analysis of alternative forming methods before the job is bid. Using breakeven charts is the best way to compare the dramatically different forming methods. They show the relationship between forming costs and the number of pours on a job. Read more

Features Machine Control by Laser

Laser-controlled machines give the operator instant feedback on his cutting position. A laser transmitter, emitting a thin 360 degree rotating beam, provides a constant grade reference to a receiving system mounted on the blade of the machine. The receiver detects the laser signal and then indicates whether the cutting edge is above, below, or on grade. Read more

Features Softening the Insurance Crunch

The easiest way to reduce insurance cost is to eliminate unnecessary coverages. When you cancel or delete coverage, you are assuming the risk yourself. Assuming the risk yourself is possible because either the risk is very small or remote, or the cost of the claim can be readily absorbed as a business expense. Read more

Features Designing for the Economy

Designers can reduce the cost of concrete construction by following these design rules for formwork, reinforcement, and concrete: Read more

Features Board Marked Concrete Made to Order

The Orlando Public Library, the largest public library in Florida, is a noteworthy example of how historic preservation can be achieved while expanding the size of a building. Read more

Features Concrete Pumps Complete Massive Foundation Pour in 13.5 Hours

On a Seattle foundation job in the summer of 1988, nine concrete pumps set West Coast records for placing concrete. After the first hour of pumping, with no truck-waiting time, a remarkable 1,350 cubic yards of concrete were in the hole. The boom pumps had placed a record-breaking volume that averaged 150 yards per unit. The nine pumps kept pace with the 115 ready mix trucks, enabling the continuous pour to be completed in 13.5 hours. Read more

Features Alice in Wonderland Image Hidden in Concrete

A 1,5000-square-foot sculpture in concrete brought Alice in Wonderland to the courtyard of the Waters Landing Elementary School, Germantown, Maryland. Read more

Features Staying Out of Court

Arbitration is playing an increasing role in settling construction disputes. Arbitration often settles a construction dispute faster and at less cost than going to court. Arbitrated construction hearings usually involve two parties who are having a contract dispute and an arbitrator they jointly chose to resolve the dispute. The American Arbitration Association (AAA), a nonprofit organization founded in 1926, operates from more than 30 offices nationwide to help resolve more than 46,000 disputes annually. Read more

Features Myths About Wage-Hour Laws

Many contractors don't understand all provisions of the Fair Labor Standards Act (FLSA). They should, though, because contractors caught ignoring the law may have to make a single payment of up to 2 years back pay. Making wrong assumptions about the law can be costly to contractors, so don't get caught believing these common myths: Read more

Features Proving Claims with Pictures

In court, contractors should illustrate their claims with charts and pictures to help lawyers, juries, and judges understand actual damages. Read more

Features How Much Is Your Time Worth?

Studies indicate that idle time on most construction projects averages above 30 percent. Read more

Features Building Largest Testing Facility: an Unforgettable Construction Project

Construction superintendent Kurt Baer was astounded to learn that his latest project, the world's largest structural testing facility at Lehigh University, Bethlehem, Pennsylvania, required nearly 1,000 tons of rebar. Read more

Problem Clinic Specs for Epoxy-Coated Welded Wire Fabric

We heard that epoxy-coated welded wire fabric is being used. Is there a standard specification for the material? Read more

Problem Clinic Keystone Finish for Flatwork

Specifications for a concrete deck for a swimming pool call for a keystone finish. What is it? Read more

Problem Clinic Bugholes Near the Top of a Wall

We've got problems with bugholes in an 8-inch-thick architectural concrete wall that we're building. It's 4 to 6 feet high and the surface looks fine, except in the top 1 foot where lots of bugholes have formed. The air-entrained concrete is colored with Read more

Problem Clinic Shallow Surface Holes That Aren't Popouts

We've got some holes that look like popouts in our concrete sidewalk. Read more

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