Steel Erection questions for the CHST

Question 1

A controlling contractor is preparing to let a steel erector start setting columns on new cast-in-place concrete piers. Field-cured cylinder breaks, tested by an appropriate ASTM method, show the concrete has reached 60 percent of the intended minimum compressive design strength. The engineer has not stated that the piers can support the erection loads. What should the steel erection contractor do?

1. ABegin erecting, because 60 percent is enough as long as verbal approval is given on site
2. BBegin erecting, but limit the work to the perimeter columns until the concrete reaches 100 percent of design strength
3. CNot erect steel until it has written notification that the concrete has reached 75 percent of design strength or sufficient strength to support erection loads
4. DBegin erecting once the controlling contractor has verified that the access roads are graded

Question 2

A steel erection crew has established a marked controlled decking zone (CDZ) on a floor 24 feet above the level below, and metal decking is being placed at the leading edge. To save time, the foreman wants a CDZ-trained employee to weld shear connectors and make final deck attachments on panels already placed inside the CDZ while the leading-edge crew keeps working. Unsecured decking in the zone is well under the allowed area, and each panel already has two safety deck attachments. What does the standard require?

1. AThe work is allowed because the employee has completed CDZ training and the panels already have two safety attachments each.
2. BThe work is allowed as long as unsecured decking in the CDZ stays under the maximum area.
3. CThe work is allowed if the employee is moved to the leading edge and protected from falls of more than two stories or 30 feet.
4. DThe work must be done outside the CDZ, because final deck attachments and shear connector installation are not permitted inside it.

Question 3

A steel erection crew is installing metal decking at a leading edge under a controlled decking zone (CDZ). The foreman proposes this plan for the shift: (1) lay panels and make safety deck attachments working from the leading edge back toward the control line; (2) keep unsecured decking within the CDZ under the allowed limit; and (3) have a second crew of trained leading edge workers install the shear connectors and make the final deck attachments inside the CDZ while the first crew continues forward. Which part of the plan violates the standard, and what must the foreman change?

1. AStep 1 violates the standard because safety deck attachments must be made from the control line forward toward the leading edge
2. BStep 2 violates the standard because no unsecured decking may be present in a CDZ at any time
3. CStep 3 violates the standard only because the second crew must be different employees who have not completed CDZ training
4. DStep 3 violates the standard because final deck attachments and shear connector installation must not be performed in the CDZ, so that work must be moved outside the CDZ