Civil and Materials Engineering: Ethics, Pavements, Materials, and Mechanics

ASCE Code of Ethics: Public Safety, Health, and Welfare

The ethical duty of engineers to put public safety, health, and welfare above everything else, including client or employer wishes, and to notify proper authorities if their judgment is overruled and public safety is endangered.

ASCE Code of Ethics: Competence

The ethical requirement that engineers only perform services in areas where they are qualified by education or experience and refrain from taking on work they are not competent to do.

Faulting

A PCC pavement distress characterized by a height difference between adjacent slabs at a joint or crack, usually caused by pumping or loss of support under the slab.

Corner Break

A PCC pavement distress involving a crack that cuts off a corner of a slab, caused by loss of support and repeated loading near joints.

Spalling

A PCC pavement distress involving the chipping or breaking of concrete along joints or cracks, often caused by incompressible material in joints or weak concrete.

Transverse and Longitudinal Cracking

PCC pavement distresses consisting of cracks across or along the slab caused by traffic loads, shrinkage, and temperature or moisture curling.

Cement Type I

Normal or general purpose portland cement used when no special properties are required.

Cement Type II

Portland cement offering moderate sulfate resistance and moderate heat of hydration.

Cement Type III

High early strength portland cement used when forms must be removed fast or during cold weather.

Cement Type IV

Low heat of hydration portland cement used in massive concrete pours such as dams.

Cement Type V

High sulfate resistance portland cement used where surrounding soil or water contains high levels of sulfates.

Jointed Plain Concrete Pavement (JPCP)

PCC pavement constructed without reinforcing steel that uses short joint spacing to control cracking.

Jointed Reinforced Concrete Pavement (JRCP)

PCC pavement that incorporates steel reinforcement and longer joint spacing.

Continuously Reinforced Concrete Pavement (CRCP)

PCC pavement featuring continuous steel reinforcement and no transverse joints, causing it to form tight, closely spaced cracks.

Normal Stress ($\sigma$)

The stress plotted on the y-axis of a normal stress-strain graph, plotted against axial strain ($\varepsilon$) on the x-axis.

Elastic Modulus ($E$)

The slope of the normal stress-strain relationship ($E = \frac{\text{stress}}{\text{strain}}$), also known as Young's Modulus.

Shear Stress ($\tau$)

The stress plotted on the y-axis of a shear stress-strain graph, plotted against shear strain ($\gamma$) on the x-axis.

Shear Modulus ($G$)

The slope of the shear stress-strain curve.

Elastic Deformation

Deformation that is fully recovered when the applied load is removed, returning the material to its original shape; it requires larger stress for a given recoverable strain.

Plastic Deformation

Permanent, unrecoverable deformation occurring past the elastic limit that produces high