ABSTRACT
Buildings are connected to the earth by foundation systems to achieve stability. Utilities are
located underground so that they are not visible and not placed in the way of other systems.
Building sites are shaped to drain water away from the structure to a safe place. Bridges
spanning rivers and valleys or tunnels through mountains provide suitable safe surfaces for
travel. Refineries provide fuel for cars traveling on our highways and bridges. Dams are built to
change the face of the earth, harness to change natural power, and provide an essential resource
to our existence, namely water. Construction of these projects requires heavy equipment or ‘‘big
iron’’ to assist many of the work activities. At the start of the 21st century, construction
accounted for approximately 10% of the U.S. gross national product and employed approxi-
mately 4.5 million people. Heavy construction equipment is one of the primary reasons
construction has reached this status. In fact, the role of heavy construction equipment today
is ‘‘mission critical’’ and indirectly influences the quality of our lives everyday.
