Navigation of an Autonomous Robot Vehicle
The U.S. Air Force has developed an autonomous excavator capable of performing a variety of tasks at various Department of Defense facilities. Common to all the tasks is the need for autonomous...
Developing Plans for Robotic Excavators
We would like a robot excavator that is able to excavate a volume of soil according to specification. To this end we have developed a general method that can be used to provide prescriptions...
Intelligent Excavator Control for a Lunar Mining System
The benefits of utilizing local planetary resources are a large reduction in the cost of lifting materials from the earth's surface into earth orbit. Since the moon is one of the closest...
Control Model for Robotic Backhoe Excavation and Obstacle Handling
Excavation of soil and rock is a high volume and repetitive construction operation. Robots, which are suitable for incessant and repeated manipulations, can find many potential applications....
A Near-Term, Long-Duration, Lunar Outpost Design
The design of a long-term human outpost on the Moon will require shielding from not only solar proton and galactic cosmic radiation but also from micro-meteoroid and meteoroid strikes....
The Challenge of Mining He-3 on the Lunar Surface: How All the Parts Fit Together
After the initial confirmation of the existence of He-3 on the lunar surface in 1985, there has been a flurry of activity both in the U.S. and abroad to find the best method of garnering...
Monitoring of Structures During Repair of Underground Utilities
A collapse of underground utilities at a power plant required the constant monitoring of the surrounding structures during excavation and replacement of the damaged pipes. A computer-based...
An Overview of Shotcrete Usage on the SSC
Shotcrete has been widely used on the Superconducting Super Collider for initial support of tunnel excavations in both the strong and weak rock formations encountered. Different types...
Prediction of Ground Deformations Due to Excavation-Application to Tunnel Lining Design in Weak Rock
Prediction of ground deformations due to excavations is simulated by three dimensional non-linear finite element analyses. It considers various in-situ ground stress levels, excavation...
Deformations About Excavations in Highly Stressed Rock
The central business district of Sydney, New South Wales (NSW), is dominated by the Hawkesbury Sandstone, a Triassic sedimentary formation. Measurements have confirmed the existence of...
Jet Grouting Gains
Jet grouting, a soil stabilization technology developed in Europe, was introduced in the U.S. in the early 1980s. Due, in part, to the use of inappropriate equipment, jet grouting got...
Taming the Urban Underground
When designing and installing excavation support systems at a city construction site, be prepared to deal with the urban jungle. Tunnels and utility cables and pipes clog the underground,...
High-Grade Concrete for the Single Permanent Shotcrete Lining Method
With the single permanent shotcrete lining method in underground construction in rock, a shotcrete layer placed subsequently to the application of the supporting shotcrete replaces the...
Design and Application of Integrated Shotcrete Linings for Underground Openings in Weak Rock Masses
Tunnels and caverns excavated in weak rock masses require special consideration in terms of shotcrete lining design. Shotcrete as a support medium for weak rock provides major benefits...
Active Tunnel Design?A New Concept for Predesign, Contractual Lay-out and Construction Management
Active tunnel Design is a new concept for design, layout of specification and contract, and for construction management of tunnels and underground carverns. Investigations yeild more information...
Austrian Guideline and National Report on the Use of Shotcrete
The purpose of this guideline is the standardization of quality and a uniform procedure for the production and testing of shotcrete from the technical and engineering point of view. In...
Site Measurement of Shotcreting Dust
Shotcreting is broadly used today as an excellent lining system, which enables to assure rapidly the stability of excavated rock surface. This system however leaves room for improvements...
Block Dynamics Modeling in Support of Seismic Design
The behavior of an underground excavation is usually characterized by stresses and displacements which develop around the excavation as a result of prevailing field conditions. For conventional...
Use of Shotcrete on Recent Tunnel Projects in the South and East, USA
Shotcrete and rockbolts are now the primary method of ground support for the majority of rock tunnels in America. This paper describes the use of shotcrete and some of the shotcreting...
Soil Nailing Technique in Tunnel Support
Authors have developed a new pre-lining method (PASS method) in which thin archshell lining is formed ahead of the tunnel face before the excavation to reinforce the ground. This method...
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