Introduction
Structural design has existed since mankind first built structures, designed machines, and solved engineering problems. It is an important concept in many engineering disciplines, including aerospace, civil, mechanical, and engineering mechanics. As society and technology has progressed, structural design has grown in its influence and sophistication of methods. Today’s modern structural designs bear little resemblance to the first projects attempted by mankind long ago.

General Structural Design Process
Like many engineering design procedures, structural design is an iterative process. Historically, it has been synonymous with many successes and failures. However, man’s resolve has turned many of these failures into successes. Simply put, structural design is a decision-making process that involves translating the customer’s requirements into an acceptable engineering solution. Within each engineering discipline, the specifics of the structural design process vary, but the general principle of meeting design requirements is constant.

Basics of Structural Design
Structural design is based on the laws of physics, as they are applied to engineering problems. This includes application of new theory and tried and true methods that have been proven (oftentimes by testing) throughout the years. The principles of tensile, compressive, and bending strength are commonly examined during the structural design process. Most structures can be broken down into basic elements including beams, columns, and plates and shells. The introduction of finite element analysis allows present day designers to assemble the structure into a composite body for evaluation during the preliminary and detail design phases of a project.

Aerospace Engineering Structural Design
Structures are the main component of most airborne and space borne products. Failure of aerospace structures can lead to loss of life, or, as a minimum, loss of a very expensive vehicle. The design requirements for aerospace structures include acceleration, aerodynamic loading, temperature extremes, vibration, and pyrotechnic shock. Fatigue is a concern for commercial aerospace projects, while large dynamic loads are an important consideration for space borne structures. Software developments have created a variety of solution methods that help today’s aerospace engineer solve complex problems.

Civil Engineering Structures
Civil engineering structures are dominated by a wide variety of buildings, including commercial and residential variations. Besides buildings, projects in the civil realm include bridges, highways, dams and airports. These structures must be designed for a wide variety of physical and environmental loads, including wind, seismic loading, dead weight, temperature, and fatigue. One of the unique aspects of civil engineering structures is their materials. Steel, concrete, and wood comprise the materials of choice for many of these projects. Building design must also provide a structure that is easy to build and meets local building codes. Civil engineering structures are critical to the success of large-scale development projects that. These structures must be designed to safely protect both people and their possessions.

Mechanical Engineering Structural Design
Structural design in the mechanical engineering world involves a wide variety of applications. One aspect of mechanical structures is that they can be used in stationary, static applications; or they can be used in moving, dynamic situations. This can make the design process more complicated, but modern tools in the analytical regime make the engineering process easier. Since machine design is such a large part of mechanical engineering, structural design of each part is necessary for the success of the overall design process. Understanding loads and unique customer requirements is critical to the design of mechanical products. The design process can involve linear statically determinate structures, or it can involve non-linear indeterminate structures. In all cases, the structural design team must be equipped to ensure that each structural part meets the design requirements.

Vibration Analysis Introduction
Vibration analysis training is a necessary process for engineers and technicians who desire to understand the vibration that exists in structures and machines. There are two types of vibration analysis tasks that are regularly done today. The first involves predicting the mechanical vibration that will exist in new products. The second involves evaluating the vibration that occurs in rotating machinery such as motors, pumps, and compressors. Advances in technology have greatly enhanced the vibration analysis process for both new and existing products. It is important for professionals in the vibration industries to keep up with the state-of-the-art in vibration analysis techniques.

Vibration Analysis Basics
Whether you are predicting the vibratory response of a new product, or you are analyzing the vibration that occurs in an existing product, vibration analysis is the study of resonance. Resonance occurs at specific frequencies (natural frequencies), where the vibration of the product is increased. Called modal analysis, this process is crucial to understanding the vibration behavior of any product. Once the fundamentals of vibration analysis are learned, vibration analysis training can proceed to more complicated topics, such as finite element analysis.

Finite Element Analysis
Finite element analysis (FEA) is normally used for vibration analysis of new product designs. This method allows the analyst to consider real-world structures that cannot be analyzed with elementary vibration analysis training. Using FEA for vibration analysis involves dividing the structure into a number of elements, and then performing a modal analysis. Using a defined vibration excitation (random vibration, for instance), FEA software is then used to predict the vibratory stresses in the structure. Vibration in existing machinery is analyzed with vibration analysis equipment and integrated software.

Machinery Vibration Measurement
Vibration analysis training is necessary for analyzing and evaluating the mechanical vibration that occurs in rotating machinery, such as motors, pumps, and bearings. Today’s vibration measurement equipment utilizes software that simplifies the analysis of machinery vibration performance. Multiple vibration data parameters are assessed to predict machinery operation. Called vibration condition monitoring, this procedure involves processing large quantities of data to determine if unscheduled maintenance is necessary, or if shutdown is required.