PE Civil: Structural key terms

A scheduling technique that finds the longest chain of dependent activities in a project; any delay along this chain pushes out the project completion date.

A project-control method that compares the budgeted value of work performed with actual cost and schedule to forecast overruns.

Shop drawings, product data, or samples that a contractor sends to the designer for review and approval before the related work is fabricated or installed.

A written modification to the contract documents that adjusts scope, price, or schedule after the original contract is signed.

A structured review that seeks lower-cost ways to provide the required function and performance of a design, often proposed by the contractor during construction.

Temporary supports, often vertical or inclined, that hold an excavation wall, slab, or structure in place while permanent work is built.

Strengthening or deepening the foundation of an existing structure so it can carry new loads or tolerate adjacent excavation.

Temporary molds and supporting falsework that shape and hold fresh concrete until it hardens enough to carry its own weight.

Lowering the groundwater level at a site by pumping or drainage so excavations can proceed in dry, stable soil.

Maintaining adequate moisture and temperature in freshly placed concrete so cement hydration continues and the desired strength and durability develop.

A manufacturer-supplied table or graph giving the maximum safe load a crane can lift at each boom length, radius, and configuration.

A hand method that releases joints of an indeterminate frame, distributes unbalanced moments in proportion to member stiffness, and carries over fixed-end moments until the joints balance.

A matrix analysis approach that treats joint displacements as unknowns, assembles member stiffness properties, and solves equilibrium equations for displacements and member forces.

The number of redundant reactions or internal forces beyond those required by equilibrium; it equals unknown forces minus available equilibrium equations.

The portion of a floor or roof area whose loads are assumed to be carried by one particular beam, column, or wall.

The extra forces and sidesway produced when gravity loads act through the laterally displaced shape of a structure, amplifying moments and drift.

The continuous route by which gravity, wind, and seismic forces travel from where they are applied through the structure to the foundation.

The mass of water divided by the mass of cementitious material in a concrete mix; a lower ratio generally raises strength and lowers permeability.

A standard fresh-concrete test that measures consistency as the vertical drop of a molded cone after the form is removed.

The slope of the straight portion of a stress-strain curve, expressing how stiff a material is within its elastic range.

Time-dependent deformation of a material under sustained stress, occurring in concrete and wood even when the load does not increase.

Volume reduction of concrete as it dries and hardens, which can cause cracking when restrained and contributes to loss of prestress.

The stress at which a material begins to deform permanently, commonly found for steel by the 0.2 percent offset method.

Reduction over time of the initial tension in prestressing steel caused by shrinkage, creep, relaxation, friction, and anchorage slip.

A beam-to-column joint detailed to transfer bending moment as well as shear, keeping the angle between the connected members nearly unchanged under load.

A bolted joint designed so that friction between clamped plies carries the load and no slip occurs at service-level forces.

A steel plate at the bottom of a column that spreads the column load onto concrete and anchors the column in place.

A threaded rod embedded in concrete or masonry that fastens a base plate or other steel element to the foundation and resists uplift and shear.

A steel beam and a concrete slab joined by shear connectors so they act together as a single flexural member.

A member in a floor or roof diaphragm that gathers lateral forces and delivers them to the vertical lateral-force-resisting elements.

A wall designed to resist in-plane lateral forces, providing the stiffness and strength a building needs for wind and earthquake loads.

A prescribed set of factored or service loads applied together in design, reflecting the likelihood that different load types act at the same time.

A design method that multiplies loads by factors greater than one and compares the result with a factored resistance, giving consistent reliability across materials.

A seismic design coefficient that reduces elastic base shear to account for a system's ductility, overstrength, and redundancy.

The total design lateral force at the base of a structure, computed from seismic or wind provisions and distributed over the building height.

The lateral displacement of one floor relative to the floor below, often expressed as a ratio to story height and limited to control damage.

A seismic detailing philosophy that makes beams yield before columns so plastic hinges form in ductile beams rather than in critical columns.

The presence of multiple load paths or members so that failure of one element does not cause collapse of the whole system.

A floor or roof system that acts as a horizontal plate, transferring lateral forces to the vertical elements that resist them.