Posts Tagged engineering
Methods for Measuring Bending Stresses in Structural Engineering
Posted by Adam Wilson in General Engineering, Latest News on September 1st, 2008
Measuring bending stresses is an important part of structural engineering. Measuring bending stresses determines how much load a structure can support before it fails. Building structurally sound projects is the ultimate goal of successful structural engineering.
Measuring Bending Stresses
Measuring bending stresses requires determining the average amount of force exerted on an area that results in distortion or failure of the material. Understanding these values is crucial in determining the limits of construction materials.
Methods for Measuring Bending Stresses in Commercially Available Construction Materials
With the advent of new composite materials, measuring bending stresses has become a crucial ongoing investment of research dollars for scientists and engineers. One of the newest methods of measuring bending stresses is the use of piezoelectric PVDF (polyvinylidene-fluoride) film sensors.
Researchers have reported that a 25 µm thick PVDF strip used as an embedded interfacial stress sensor on aluminum and composite beams adequately measures bending stresses of the building materials. Engineers have also used these PVDF strips to measure other forces such as interfacial stresses and the adhesion strength of laboratory recreated layers of ice that might occur on the outside of a structure once constructed.
Another method of measuring bending stresses is to clamp gauges at key points of an existing structure to measure the bending moment of different types of materials used in the structure. By studying this data, scientists can learn vast amounts of information about the bending behavior of different construction materials once they are used in the field. This method also allows engineers to measure bending stresses over an extended period of time, allowing researchers to factor in other variables such as weather, corrosion, and alternating live loads.
Alternatively, engineers can measure bending stresses by attaching a hollow bar with strain gauges on its inner surface in a manner that allows part of the bar to move longitudinally along its axis with respect to the structure itself.
In Japan, researchers have experimented with measuring bending stresses in micro-cantilever structures by using a macro model using a micro-fizeau interferometer and the spatial fringe analysis method. Comparison of these test results with other measurements obtained from traditional gauge measurements shows that this method is effective in measuring bending stresses.
Other methods of measuring bending stresses indirectly are under consideration by the U.S. Patent Department and may revolutionize the way structural engineers study the measurement of bending stresses in the near future.
The Most Used Engineering Terminology Defined
Posted by Adam Wilson in Engineering Resources, Latest News on August 18th, 2008
The most used engineering terminology can be confusing to the average consumer. Understanding the common jargon used in structural engineering can help you communicate with your architect, engineer, or construction manager more effectively.
Beam
A structural member, usually horizontal, with a main function to carry loads cross-ways to its longitudinal axis. These loads usually result in bending of the beam member. Examples of beams are simple, continuous, and cantilever.
Beam-Column
This is a structural member whose main function is to carry loads both parallel and transverse to the longitudinal axis.
Cantilever
Cantilever refers to the part of a member that extends freely over a beam, which is not supported at its end.
Collateral Load
Collateral load is additional dead loads (not the weight of people and not the weight of the building itself), such as plumbing, duct work, ceilings, and other components of the structure.
Column
A column is a main vertical member that carries axial loads from the main roof beams or girders to the foundation parallel to its longitudinal axis.
Continuity
Continuity is the term given to a structural system describing the transfer of loads and stresses from member to member as if there were no connections.
Damping
Damping is the rate of decay of amplitude for floor vibrations.
Dead Load
Dead load describes the loads from the weight of the permanent components of the structure.
Deflection
Deflection is the displacement of a structural member or system under a load.
Dynamic Load
This type of load varies over time.
Footing
A footing is a slab of concrete under a column, wall, or other structural to transfer the loads of the member into the surrounding soil.
Foundation
A foundation supports a building or structure.
G-Type Joist Girder
A type of Joist Girder using joists located at panel points where diagonal webs intersect the top chord of the joist only.
Gable
A gable is located above the elevation of the eave line of a double-sloped roof.
Gage
Gage can refer to the thickness of a sheet of material or the distance between centerlines in a set of holes, usually perpendicular to the joist or joist girder.
Girder
A girder is the main horizontal member spanning between two main supports and carries other members or vertical loads within the structure.
Grade
The ground elevation of the soil.
Header
A member that carries other supporting members and is placed between other beams.
Hip Roof
A roof sloping from all four sides of a building.
Joist
A structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member.
Kip
1000 pounds.
Live Load
Non-permanent loads on a structure created by the use of the structure.
Load
An outside force that affects the structure or its members.
Modulus of Elasticity (E)
The value is usually 29,000 ksi for structural steels and is also called Young’s Modulus. It calculates the slope of the straight-line portion of the stress-strain curve in the elastic range.
Moment
Moment is the tendency of a force to cause a rotation about a point or axis which in turn produces bending stresses.
Moment of Inertia (I)
A measure of the resistance to rotation offered by a member’s geometry and size.
Pitch
Pitch is the slope of a member defined as the ratio of the total rise to the total width
Reaction
Reaction is the force or moment developed at the points of a support.
Seismic Load
Loads produced during the seismic movements of an earthquake.
Shear
Forces resulting in two touching parts of a material to slide in opposite directions parallel to their plane of contact.
Span
The distance between supports.
Structural Steels
Steels suitable for load-carrying members in a structure.
Strut
A structural brace that resists axial forces.
Stud
A vertical wall member used to attach other structures, such as walls.
Torsion Loads
A load that causes a member to twist about its longitudinal axis. A couple or moment in a plane perpendicular to the axis produces simple torsion.
These most used structural engineering terminology definitions provide a baseline understanding of engineering jargon for the average consumer. Detailed definitions can be obtained from visiting a professional engineering website or professional journal.
The Science of Structural Engineering
Posted by Adam Wilson in General Engineering on July 21st, 2008
The science of structural engineering is constantly evolving. Structural engineers continually look to develop new architectural designs to please clients. As new building materials emerge, structural engineers are pushed to integrate these materials into new construction. They must study the way these materials react under the stress of load and predict how to support key areas strategically to maintain the structural integrity of the structure.
The science of structural engineering helps structural engineers build more stable structures while pushing the current limits of design as we know it. By studying the science behind the factors that affect the stability of structures, structural engineers can design and build structures that can withstand the forces of nature and loads, even under extreme circumstances.
Structural engineering relies on the predictability of nature. Forces like wind, water, snow, and weight affect building materials in a predictable manner. The structural engineer takes these reliable principles and designs a system of supports that will resist the warping nature of these elements. Structural engineers design structures to be flexible enough to move and flex without breaking. This requires a delicate balance of design and science.
The science of structural engineering is taught in colleges and universities around the world to prospective structural engineering students. Structural engineering students study the effects of nature on structures and common building materials. They study how a fully loaded building sags and moves in a strong wind. Then, they apply these observations to the structural designs they create after graduation.
Structural engineers apply the science of structural engineering to the structural designs they create in order to produce better structures. Special structural engineers develop designs for structures in earthquake regions. These special designs are crafted to help minimize damage during an earthquake and save lives by preventing the total collapse of a building.
The science of structural engineering involves the principals of physics, geometry, and basic mathematics. Structural engineering is a concrete science, with an artistic element. Structural engineers must also be able to design visually appealing structures according to a client’s specifications and be able to adapt well enough to work with architects and builders as well.
The science of structural engineering affects our everyday lives, but many people never stop to think about the strength and stability of the homes they live in, the office they work at, or the bridge they drive across. Structural engineering enhances the lives of people throughout the world.
Structural Engineering and Geometry
Posted by Adam Wilson in General Engineering on July 14th, 2008
Structural engineering and geometry are intertwining subjects. Since the very first Egyptian structural engineers began building pyramids, geometry has been used to help solve structural stability problems. Geometry has been woven into the development of structural engineering for centuries.
What is Structural Engineering?
A structural engineer’s goal is to design structures that can both support and resist loads. A structural engineer designs structures and analyzes them for structural soundness. Structural engineering is closely related to architecture.
What is Geometry?
Geometry is a branch of mathematics that deals with the size, shape, and relative position of physical elements. Geometry also deals with the properties of space. Geometry looks at the length, width, height, and space of an object. Basic geometry is taught to high school students all across America.
Structural Engineering and Geometry in History
Examples of structural engineering intersecting geometry studies can be found throughout history. Some examples are even well known.
The Virtual Work Theory Structural Engineering and Geometry at Work
Structural engineering and geometry have evolved together over the years. Daniel Bernoulli, along with Johann (Jean) Bernoulli (1667-1748), is credited with formulating the theory of virtual work. The virtual work theory provides builders and structural engineers with a tool that uses the equilibrium of forces and compatibility of geometry to solve structural problems.
Archimedes: Structural Engineering and Geometry in History
The Greek engineer, Archimedes studied geometry extensively in his quest for building better structures and machines. Geometry played a large part in Archimedes’ experiments.
Euclidean Geometry, Preparing the Way for Structural Engineering
Euclidean geometry is also credited with contributing to modern day structural engineering. The ancient Greek mathematician Euclid wrote about Euclidean Geometry. Euclid’s book, Elements, was the first known written explanation of geometrically principals.
Geometry has strongly influenced the development of structural engineering. The principals researched in studying geometry have shaped structural engineering into the precise science we have today. Ancient Greek principal taught centuries ago are used today to create structurally sound high rise buildings, innovative shopping centers, and single family dwellings.
Structural engineering and geometry influence the way buildings are designed and built today. Geometry is an important part of the structural engineer’s industry.
