Author: DJ. DeGroot
Publisher:
ISBN:
Category : Laboratory equipment
Languages : en
Pages : 10
Book Description
This paper describes the design and implementation of an automated electropneumatic control system for direct simple shear testing of cohesive soils. The hardware and software used to perform automated application of consolidation increments and for subsequent constant volume shear of soil specimens is described in detail. Two servo-control algorithms are used to conduct a test, one for application of consolidation increments and another for maintaining constant volume during undrained shear. It is shown that a servocontrol system using a proportional controller can successfully control stress during consolidation increments but cannot control displacement by varying stress as required during undrained shear of cohesive soils. Results are presented which show that while the proportional controller can successfully perform displacement control for mechanical and hydraulic systems it cannot do so for more compliant pneumatic systems. This is primarily due to the fact that pneumatic systems are significantly less rigid due to the high compressibility of air as compared to the compressibility of mechanical systems and hydraulic fluids. While attempting to maintain constant height of the specimen, as is necessary to maintain constant volume during undrained shear, the pneumatic-based system falls into an irrecoverable oscillation of the vertical stress. It is shown that the undrained shear portion of a test required the implementation of the more sophisticated proportional plus integral plus derivative (PID) controller. Unlike the proportional controller, the PID controller easily maintains constant height of the specimen during undrained shear without instability in the vertical stress. Results are given comparing the performance of both the proportional controller and the PID controller during undrained shear of a cohesive soil specimen.
An Automated Electropneumatic Control System for Direct Simple Shear Testing
Author: DJ. DeGroot
Publisher:
ISBN:
Category : Laboratory equipment
Languages : en
Pages : 10
Book Description
This paper describes the design and implementation of an automated electropneumatic control system for direct simple shear testing of cohesive soils. The hardware and software used to perform automated application of consolidation increments and for subsequent constant volume shear of soil specimens is described in detail. Two servo-control algorithms are used to conduct a test, one for application of consolidation increments and another for maintaining constant volume during undrained shear. It is shown that a servocontrol system using a proportional controller can successfully control stress during consolidation increments but cannot control displacement by varying stress as required during undrained shear of cohesive soils. Results are presented which show that while the proportional controller can successfully perform displacement control for mechanical and hydraulic systems it cannot do so for more compliant pneumatic systems. This is primarily due to the fact that pneumatic systems are significantly less rigid due to the high compressibility of air as compared to the compressibility of mechanical systems and hydraulic fluids. While attempting to maintain constant height of the specimen, as is necessary to maintain constant volume during undrained shear, the pneumatic-based system falls into an irrecoverable oscillation of the vertical stress. It is shown that the undrained shear portion of a test required the implementation of the more sophisticated proportional plus integral plus derivative (PID) controller. Unlike the proportional controller, the PID controller easily maintains constant height of the specimen during undrained shear without instability in the vertical stress. Results are given comparing the performance of both the proportional controller and the PID controller during undrained shear of a cohesive soil specimen.
Publisher:
ISBN:
Category : Laboratory equipment
Languages : en
Pages : 10
Book Description
This paper describes the design and implementation of an automated electropneumatic control system for direct simple shear testing of cohesive soils. The hardware and software used to perform automated application of consolidation increments and for subsequent constant volume shear of soil specimens is described in detail. Two servo-control algorithms are used to conduct a test, one for application of consolidation increments and another for maintaining constant volume during undrained shear. It is shown that a servocontrol system using a proportional controller can successfully control stress during consolidation increments but cannot control displacement by varying stress as required during undrained shear of cohesive soils. Results are presented which show that while the proportional controller can successfully perform displacement control for mechanical and hydraulic systems it cannot do so for more compliant pneumatic systems. This is primarily due to the fact that pneumatic systems are significantly less rigid due to the high compressibility of air as compared to the compressibility of mechanical systems and hydraulic fluids. While attempting to maintain constant height of the specimen, as is necessary to maintain constant volume during undrained shear, the pneumatic-based system falls into an irrecoverable oscillation of the vertical stress. It is shown that the undrained shear portion of a test required the implementation of the more sophisticated proportional plus integral plus derivative (PID) controller. Unlike the proportional controller, the PID controller easily maintains constant height of the specimen during undrained shear without instability in the vertical stress. Results are given comparing the performance of both the proportional controller and the PID controller during undrained shear of a cohesive soil specimen.
Nondestructive and Automated Testing for Soil and Rock Properties
Author: W. Allen Marr
Publisher: ASTM International
ISBN: 0803124937
Category : Automatic test equipment
Languages : en
Pages : 326
Book Description
Publisher: ASTM International
ISBN: 0803124937
Category : Automatic test equipment
Languages : en
Pages : 326
Book Description
Advanced Earthquake Engineering Analysis
Author: Alain Pecker
Publisher: Springer Science & Business Media
ISBN: 321174214X
Category : Science
Languages : en
Pages : 218
Book Description
During the last decade, the state-of-the-art in Earthquake Engineering Design and Analysis has made significant steps towards a more rational analysis of structures. This book reviews the fundamentals of displacement based methods. Starting from engineering seismology and earthquake geotechnical engineering, it proceeds to focus on design, analysis and testing of structures with emphasis on buildings and bridges.
Publisher: Springer Science & Business Media
ISBN: 321174214X
Category : Science
Languages : en
Pages : 218
Book Description
During the last decade, the state-of-the-art in Earthquake Engineering Design and Analysis has made significant steps towards a more rational analysis of structures. This book reviews the fundamentals of displacement based methods. Starting from engineering seismology and earthquake geotechnical engineering, it proceeds to focus on design, analysis and testing of structures with emphasis on buildings and bridges.
Journal of Geotechnical Engineering
Advances in Site Characterization
Author: Carlton L. Ho
Publisher: American Society of Civil Engineers
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 132
Book Description
Accurate site characterization is one of the most important aspects of a successful geotechnical design. This volume provides a summary of current advances in data acquisition, management, and interpretation, as contributors describe specific cases of how progress in these areas has improved accuracy of site characterization. Peer-reviewed papers detail construction of TINS from borehole data; acquisition, reduction and management of data for consolidation testing; and management of the geotechnical data for a tunnel near Paris, France, among other topics.
Publisher: American Society of Civil Engineers
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 132
Book Description
Accurate site characterization is one of the most important aspects of a successful geotechnical design. This volume provides a summary of current advances in data acquisition, management, and interpretation, as contributors describe specific cases of how progress in these areas has improved accuracy of site characterization. Peer-reviewed papers detail construction of TINS from borehole data; acquisition, reduction and management of data for consolidation testing; and management of the geotechnical data for a tunnel near Paris, France, among other topics.
Geomaterials
Author:
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 564
Book Description
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 564
Book Description
The Engineering Index Annual
Author:
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 2264
Book Description
Since its creation in 1884, Engineering Index has covered virtually every major engineering innovation from around the world. It serves as the historical record of virtually every major engineering innovation of the 20th century. Recent content is a vital resource for current awareness, new production information, technological forecasting and competitive intelligence. The world?s most comprehensive interdisciplinary engineering database, Engineering Index contains over 10.7 million records. Each year, over 500,000 new abstracts are added from over 5,000 scholarly journals, trade magazines, and conference proceedings. Coverage spans over 175 engineering disciplines from over 80 countries. Updated weekly.
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 2264
Book Description
Since its creation in 1884, Engineering Index has covered virtually every major engineering innovation from around the world. It serves as the historical record of virtually every major engineering innovation of the 20th century. Recent content is a vital resource for current awareness, new production information, technological forecasting and competitive intelligence. The world?s most comprehensive interdisciplinary engineering database, Engineering Index contains over 10.7 million records. Each year, over 500,000 new abstracts are added from over 5,000 scholarly journals, trade magazines, and conference proceedings. Coverage spans over 175 engineering disciplines from over 80 countries. Updated weekly.
Innovations in Instrumentation and Data Acquisition Systems
Author: National Research Council (U.S.). Transportation Research Board
Publisher: Transportation Research Board National Research
ISBN:
Category : Automatic data collection systems
Languages : en
Pages : 120
Book Description
Publisher: Transportation Research Board National Research
ISBN:
Category : Automatic data collection systems
Languages : en
Pages : 120
Book Description
Transportation Research Record
Automatic Flight Control
Author: Pallet
Publisher: John Wiley & Sons
ISBN: 9788126519323
Category : Automatic pilot (Airplanes)
Languages : en
Pages : 340
Book Description
This is an updated edition of the well-known introduction to the principles involved in the automatic flight of fixed-wing and rotary wing aircraft. The principles are related to the systems used in the representative types of aircraft (UK and US) currently in service.
Publisher: John Wiley & Sons
ISBN: 9788126519323
Category : Automatic pilot (Airplanes)
Languages : en
Pages : 340
Book Description
This is an updated edition of the well-known introduction to the principles involved in the automatic flight of fixed-wing and rotary wing aircraft. The principles are related to the systems used in the representative types of aircraft (UK and US) currently in service.