comparison of forces in statically determinate and indeterminate trusses
- With surplus bars a statically determinate truss becomes internally statically indeterminate.
- In this case the truss is termed statically indeterminate. In an indeterminate truss, the bar forces depend on the elastic properties of the truss and cannot be calculated easily.
- The SE 110.22experimental setup permits investigation and comparison of statically determinate and statically indeterminate trusses.
- Using the bars and node disks, a statically determinate, single plane truss is first constructed.
- On installation of a surplus bar the truss becomes indeterminate.
- By way of a load application device, straight or inclined forces are applied to the truss, thereby simulating various load cases.
- The occurring tensile and compressive forces in the bars are recorded by means of strain gauge measurement.
- Computerised evaluation of measured values is provided by measuring amplifier FL 152.
- The software in FL 152 is used to manage the measuring data and provide graphical representation of the bar forces.
- The software features a comprehensive help function.
- All the component elements of the experiment are clearly laid-out and housed securely in a storage system.
- The complete experimental setup is arranged in the frame SE 112.
- investigation of bar forces in statically indeterminate trusses
- surplus bar, longitudinally adjustable
- straight and inclined loading possible
- load application device with force gauge mountable on different node disks
- measuring point to measure force on each bar
- measuring amplifier FL 152 required
- GUNT-software in FL 152 to evaluate measured values graphically
- storage system to house the components
- experimental setup in frame SE 112
- 5 bars, fixed 300mm
- 2 bars, fixed 424mm
- 1 bar, adjustable 400…450mm
- angle between bars: 30°, 45°, 60°, 90°
- maximum bar force: 500N
- measuring point on each bar
- height of truss max. 270mm
- length of truss max. 500mm
Load application device:
- graduation: 10N
Dial gauge: measuring range: 0…20mm
Dimensions & Weight:
- L x W x H: 1170x480x178mm (storage system)
- Weight: approx. 22kg (total)
- measurement of the bar forces in a statically determinate and a statically indeterminate, single plane truss
- distribution of forces in the single plane truss dependent on the use of a surplus bar
- dependency of the bar forces on the external forcemagnitude
- , direction, point of application
- comparison of measuring results with mathematical methodsmethod of joints
- Ritter’s method of sections
- basic principle: measurement of forces using strain gauge measurement
Scope of delivery:
- 1 set of bars
- 5 node disks
- 1 load application device
- 1 dial gauge
- 1 set of cables
- 1 storage system with foam inlay
- 1 set of instructional material
- bars with strain gauge measurement to measure bar force
Due to the continuous development of our products, the goods supplied may vary in detail to that illustrated on this Website.