Application of the Surface Wave Survey Method on Multi-Scale Engineering Problems: Laboratory and Field Testing Case Studies

Coring is normally done to monitor the thickness and quality of portland cement concrete (PCC) slabs during construction. Because this procedure requires a considerable amount of time, it is done at widely spaced intervals. As a result, the most critical points, in terms of strength or thickness, are sometimes not tested. Their repeatability and extreme sensitivity to the properties of surface layer enable wave propagation techniques to be used for quality control. The main advantage of these techniques is that they are nondestructive. Fortunately, these techniques have been automated in the last few years. Two seismic devices (seismic pavement analyzer and a portable version of it called the Lunch Box) have been used extensively for quality control. With them, slabs can be tested at closely spaced points and at a fraction of the cost and time of coring. The main tests used are the impact echo for determining the thickness of the slab, the ultrasonic body wave for determining the modulus, and the ultrasonic surface wave (an offshoot of the spectral analysis of surface waves method) also for determining the modulus. On the basis of extensive field testing on many types of base and subgrade, the techniques in general—and the two devices in particular—are suitable for many quality-control projects. It was found that the most robust method for determining the modulus is the ultrasonic surface wave. The impact echo also works well, as long as enough contrast exists between the properties of the PCC and the underlying materials.

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THE IMPORTANCE OF PROPER TEST ILLUMINATION IN COLOR VISION TESTING - CASE STUDIES.

Optometry and Vision Science ◽

10.1097/00006324-200112001-00283 ◽

2001 ◽

Vol 78 (SUPPLEMENT) ◽

pp. 175

Author(s):

Christina Pellegrino ◽

Felix Barker

Keyword(s):

Case Studies ◽

Color Vision ◽

Testing Case

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Panel — Solving engineering problems in context: Preliminary results from case studies of six exemplary engineering programs

2010 IEEE Frontiers in Education Conference (FIE) ◽

10.1109/fie.2010.5673564 ◽

2010 ◽

Author(s):

Lisa R. Lattuca ◽

Carolyn Plumb ◽

Patrick T. Terenzini ◽

Lois C. Trautvetter

Keyword(s):

Case Studies ◽

Engineering Programs ◽

Preliminary Results ◽

Engineering Problems

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Assessment of VR Technology and its Applications to Engineering Problems

Journal of Computing and Information Science in Engineering ◽

10.1115/1.1353846 ◽

2001 ◽

Vol 1 (1) ◽

pp. 72-83 ◽

Cited By ~ 50

Author(s):

Sankar Jayaram ◽

Judy Vance ◽

Rajit Gadh ◽

Uma Jayaram ◽

Hari Srinivasan

Keyword(s):

Life Cycle ◽

Virtual Environments ◽

Case Studies ◽

Product Life Cycle ◽

Virtual Manufacturing ◽

Virtual Design ◽

Product Life ◽

Engineering Problems ◽

Technical Issues ◽

Product Realization

Virtual reality applications are making valuable contributions to the field of product realization. This paper presents an assessment of the hardware and software capabilities of VR technology needed to support a meaningful integration of VR applications in the product life cycle analysis. Several examples of VR applications for the various stages of the product life cycle engineering are presented as case studies. These case studies describe research results, fielded systems, technical issues, and implementation issues in the areas of virtual design, virtual manufacturing, virtual assembly, engineering analysis, visualization of analysis results, and collaborative virtual environments. Current issues and problems related to the creation, use, and implementation of virtual environments for engineering design, analysis, and manufacturing are also discussed.

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