Strain gauges are used to measure small deformations within a certain gauge length. There are several types of strain gauges, but the most dominant type is the electrical strain gauge, which consists of a foil or wire bonded to a thin base of plastic or paper (Figure 1.32). An electric current is passed through the element (foil or wire). As the element is strained, its electrical resistance changes proportionally. The strain gauge is bonded via an adhesive to the surface on which the strain measurement is desired. As the surface deforms, the strain gauge also deforms and, consequently, the resistance changes. Since the amount of resistance change is very small, an ordinary ohmmeter cannot be used. Therefore, special electric circuits, such as the Wheat- stone bridge, are used to detect the change in resistance (Dally and Riley, 2005). Strain gauges are manufactured with different sizes, but the most convenient strain gauges have a gauge length of about 5 to 15 mm. Larger strain gauges can also be made and used in some applications. (a) FIGURE 1.32 Strain gauges: (a) strain gauges with different sizes and (b) typical foil strain gauge. (b)
Strain gauges are used to measure small deformations within a certain gauge length. There are several types of strain gauges, but the most dominant type is the electrical strain gauge, which consists of a foil or wire bonded to a thin base of plastic or paper (Figure 1.32). An electric current is passed through the element (foil or wire). As the element is strained, its electrical resistance changes proportionally. The strain gauge is bonded via an adhesive to the surface on which the strain measurement is desired. As the surface deforms, the strain gauge also deforms and, consequently, the resistance changes. Since the amount of resistance change is very small, an ordinary ohmmeter cannot be used. Therefore, special electric circuits, such as the Wheat- stone bridge, are used to detect the change in resistance (Dally and Riley, 2005). Strain gauges are manufactured with different sizes, but the most convenient strain gauges have a gauge length of about 5 to 15 mm. Larger strain gauges can also be made and used in some applications. (a) FIGURE 1.32 Strain gauges: (a) strain gauges with different sizes and (b) typical foil strain gauge. (b)
Chapter2: Loads On Structures
Section: Chapter Questions
Problem 1P
Related questions
Question
Transcribed Image Text:Strain gauges are used to measure small deformations within a certain gauge length.
There are several types of strain gauges, but the most dominant type is the electrical
strain gauge, which consists of a foil or wire bonded to a thin base of plastic or paper
(Figure 1.32). An electric current is passed through the element (foil or wire). As
the element is strained, its electrical resistance changes proportionally. The strain
gauge is bonded via an adhesive to the surface on which the strain measurement is
desired. As the surface deforms, the strain gauge also deforms and, consequently, the
resistance changes. Since the amount of resistance change is very small, an ordinary
ohmmeter cannot be used. Therefore, special electric circuits, such as the Wheat-
stone bridge, are used to detect the change in resistance (Dally and Riley, 2005).
Strain gauges are manufactured with different sizes, but the most convenient
strain gauges have a gauge length of about 5 to 15 mm. Larger strain gauges can also
be made and used in some applications.
(a)
FIGURE 1.32 Strain
gauges: (a) strain gauges with
different sizes and (b) typical
foil strain gauge.
(b)
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps
Recommended textbooks for you
Structural Analysis (10th Edition)
Civil Engineering
ISBN:
9780134610672
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Principles of Foundation Engineering (MindTap Cou…
Civil Engineering
ISBN:
9781337705028
Author:
Braja M. Das, Nagaratnam Sivakugan
Publisher:
Cengage Learning
Structural Analysis (10th Edition)
Civil Engineering
ISBN:
9780134610672
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Principles of Foundation Engineering (MindTap Cou…
Civil Engineering
ISBN:
9781337705028
Author:
Braja M. Das, Nagaratnam Sivakugan
Publisher:
Cengage Learning
Fundamentals of Structural Analysis
Civil Engineering
ISBN:
9780073398006
Author:
Kenneth M. Leet Emeritus, Chia-Ming Uang, Joel Lanning
Publisher:
McGraw-Hill Education
Traffic and Highway Engineering
Civil Engineering
ISBN:
9781305156241
Author:
Garber, Nicholas J.
Publisher:
Cengage Learning