Mechanics and Material Properties

  • ductile- a material that can permanently deform before failure

  • mechanics- the study of how materials and systems react to forces and displacements

  • modulus of elasticity- a measure of the stiffness of a material

  • normalize- to standardize

  • strain- deformation per unit length

  • stress- force per unit area, or intensity of forces distributed over a given section

  • tensile test- a test in which the material is subjected to pulling forces until failure

  • yield stress- the minimum stress that causes permanent deformation

  • new urbanism- a movement to solve design problems in cities

  • sustainable development- growth that meets current needs without compromising future needs

  • population density- the number of people in a given space

  • zoning laws- laws that govern land use and structure attributes

  • urban sprawl- rapid expansion of a city towards low-density areas

  • system- a group of parts that work together to achieve a specific goal

  • inputs- everything that enters the system to achieve the desired goal

  • processes- the parts of the system that actually change the inputs into the desired products

  • feedback- provides information that the system uses to make adjustments during manufacturing

  • outputs- refers to everything the process produces

  • nondurable goods- items designed to operate for a long period of time

  • goal of a system- whatever that system is meant to accomplish

  • optimization- the process of making a system as effective as possible

  • primary processing- the first step in transforming raw materials into products

  • life cycle analysis- charting all inputs and outputs of a product’s production and use

  • strain- measure of material deformation compared to original size

  • strength- calculation of material’s stress support without compromising integrity

  • elastic deformation- material returns to original shape after stress is applied

  • elastic limit- point where elastic deformation ends and plastic deformation begins

  • failure point- point where material breaks or fractures

  • plastic deformation- material does not return to original shape after stress is applied

  • failure site- where in the object failure occurred

  • failure model- the result of a failure, such as crushed column or bent steel beam

  • failure mechanism- what physically happened during the failure

  • root cause- the design problem, material deflect, or load that led to the failure

  • dead load- the weight of the structure itself

  • live load- all other forces, including the weight of people, furniture, and appliances, as well as any additional forces such as wind or snow

  • tension- a stretching force that pulls an object apart

  • compression- a squeezing force that pushes an object together

  • bending- when a beam is suspended by both ends and a force is exerted in the middle, the top of the beam is compressed while the bottom is in tension