Excavation Technology Research Articles

Taking Fangcun District of Guangzhou as an Example to Discuss the New Joint Repair Technology of Water Distribution Network

This paper has discussed the working principle and characteristics of the new commonly used pipeline repair technology by introducing the currently commonly used pipeline repair technology. The new commonly used pipeline repair technology can be classified as two big kinds including one based on excavation and trenchless technology. When selecting the pipeline repair technology, we mainly considerate four factors: whether excavat pipeline , whether cut off the water and the time of cutting off water , the time of pipeline repair , the materials of pipeline repair, and so on . The actual situation and network features of water supply network in Fangcun district of Guangzhou are analysed , the joint repair technology strategies of water supply network which applies to Fangcun district are discussed by synthesizing the applicability, merit and demerit of new pipeline repair technology, and use these as technical reference and guidance for other similar areas .

Research on Rapid Excavation Technology of Roadway in Coal Seam with the Risk of Coal and Gas Outburst

According to the questions of long eliminating coal and gas outburst period, large projects and slow driving came from the regional measurement of drilling hole ,the paper select 2371 (1) rail transport roadway as experiment for using along seam long drilling as a regional measurement to eliminate coal and gas outburst. Since the regional measurement of along seam long drilling had been carried out, the remaining gas content decreased more than 60％, max Smax was 5.4kg/m, max qmax was 2.01/min.Both Smax and qmax were not beyond the standard. Gas concentrations were not overrun. Gas emission decreased in the roadway afterward. The regional measurement eliminated the risk of coal and gas outburst in effect. Heading face promoted 423m forward safely. The max January footage could reach 120m.Achieve driving of heading face safely and fast.

Model Test Research on Excavation Technology of a Tunnel in Altered Granite Zone

Phenomenon of surrounding rock deformation and collapse, groundwater lowering, ground collapse and cracking appeared in a tunnel project. It is necessary to guaranty construction safety and ensure the reliability of supporting structures. This paper, using large-scale model, considers the surrounding rock deformations and stress adjustments caused by cavern excavation and tunnel support in the alteration zone. It suggests engineering protective measures by summarizing the major determinant of excavation deformation.

Excavator technology for increasing the efficiency of energy wood and pulp wood harvesting

Abstract In Finland, the harvesting of small-sized thinning wood will be doubled or even tripled over the current harvesting volume. A greater area of peatlands could be harvested during winter for energy and pulpwood if contractors adopted more carriers for harvester heads based on excavator technology. The purpose of this study was to investigate why excavator-based harvesters are not used more widely for wood harvesting in these forests. The study was implemented by conducting 46 personal interviews in 2006 and 2011. The interviewees formed five groups: contractors who used excavators for harvesting, contractors who owned excavators but did not use them for harvesting, harvester head manufacturers, officers of wood procurement organizations, and vendors of excavators. The Nordic tradition of timber harvesting using wheeled harvesters was the main reason for the limited use of excavator-based harvesters. In the follow-up (2011) lack of the forest-adapted excavators was the main reason. During this study, mixes of harvesting machines have not been increased to permit winter wood procurement, even though the number of annual working hours could be increased for both excavator-based and wheeled harvesters. Existing excavators could be used more efficiently by cooperating with energy and forest industry as well as with Forest Owners’ Associations. In future, the potential of excavator technology could be realised by developing a more flexible Finnish wood procurement infrastructure that uses a wider range of harvesters in harvesting enterprises. This could also increase the overall cost efficiency of wood procurement by permitting the use of less expensive harvesting machines.

The 3-D Finite Element Numerical Analysis of Composite Soil Nailing Walls in the Foundation Pit Engineering

Combined with one foundation pit engineering in Guangzhou, the method was adopted in this paper, by which the in-situ test and finite element analysis were integrated. According to situation of study and demand of engineering, the study in composite soil nailing walls system was focused on working mechanism. The law of soil-nailing support technology for deep excavation was pointed out and summarized to provide reference to similar projects.

Study on Layered Basin Earth Excavation Construction Technology

Through comprehensively analyzing of the present earth excavation methods and combined with Kangwang road tunnel engineering earth excavation, proposing the layered basin earth excavation construction technology of excavation. We put the layered basin earth excavation construction technology of excavation in the practice of Kangwang road tunnel earth excavation, applying "MIDAS-GTS" software to simulate and cost accounting, from the technical and economic sides to validate this new layered basin earth excavation is advanced. And finally puts forward the conditions for the layered basin earth excavation, this new layered basin earth excavation construction technique can be popularized.

Study on the Shovel and Support Bracket’s Compensation for Vertical Pose’s Deviation of Roadheader

Automatic directional excavation technology in the coal mine laneway is the important research direction of integrated excavation project. Shovel and support bracket are the most key parts for keeping roadheader body stable in excavation. This paper studies the control ability and extreme position of boom-type roadheader’s shovel and support bracket, to calculate the adjustable vertical angles rang which is realized by shovel and support bracket, expanding roadheader’s automatic compensating excavation ability, meanwhile ensuring body stable. Vertical angle is one of the four kinds of basic body pose deviation parameters. This study is the research basis for the accuracy analysis of boom-type roadheader’s directional excavation. Because the depth that shovel and support brackets’ tip compress into laneway ground, is mainly determined by laneway ground hardness and body weight, and can’t be calculate accurately, paper’s end gives feedback control application of shovel and support bracket according to laneway conditions.

Study on the Section's Extreme Position of Roadheader's Cutting Arm in Coal Mine Laneway

Directional excavation technology in the coal mine laneway is the important research direction of integrated excavation project. This paper studies the changes of cutting section shape and boundary values caused by the swing of boom-type roadheader's cutting arm ​​to calculate the maximum values of compensable pose deviation when cutting, as the research basis for the accuracy analysis of boom-type roadheader's directional excavation. This paper gives the calculation method of cutting arm control, spatial modeling and analysis of cutting head position changes caused by cutting arm in thought of the three-dimensional analytic geometry, and also gives verification in the way of Matlab graphics simulation. At last, a control method to compensate section boundary by cutting arm is put forward.

ERMR System – an Useful Tool In Defining of Technology for Excavation

302 INTRODUCTION Predicting the ease of excavation of rock and rock masses is very significant for defining of technology and organisation of earthworks for civil engineering works and in surface mines. On this important scientific and practical field, several authors gave effort to establish acceptable methodologies for practical use (Franklin et al., 1971), (Atkinson, 1971), (Weaver, 1975), (Kirsten, 1982), (Abdullatif and Cruden, 1983), (Scoble and Muftuoglu, 1984), (Pettifer and Fookes, 1994), (McLean and Gribble, 1985), (Singh et al., 1987), (Church, 1981) and another’s. The reference that gives whole overview on this aspect is given by Tsiambaos and Saroglou (2009) In the present article, the term excavatability is used to determine the ease of excavation of rock and rock masses that includes the methods of digging, ripping and blasting. classification, excavation, technology of excavation, rock masses, parameters

A state-of-the-art review of mechanical rock excavation technologies

The first step in mining activities is rock excavation in both mine development and production. Constant pressure for cost reduction and creating an improved/safe work environment for personnel has naturally resulted in increased use of mechanical excavation systems in many mining operations. Also, mechanical excavation and mining is more compatible with automation, meaning possibility of reduction in number of people in the active underground mines. This factor plays a major role in selection of mining systems especially considering the dire shortage of skilled labour in the industry. While these systems are an integral part of mining activities in underground soft rock mining (coal, salt, potash, trona etc.), there is a need for developing new approaches and machinery for use in the underground hard rock mining. This paper will offer a review of current and emerging technologies for mechanical hard rock excavation, including disc cutting technology, drag picks, mini-disc, and activated/oscillating disc cutter. A review of general guidelines for assessment of the potentials of new research and development on this topic and evaluation of emerging technologies for a specific mining application will also be offered.

Outburst control technology for rapid excavation in severe outburst coal

The advantages and disadvantages of various outburst prevention measures in heading face were analyzed. The mechanism of outburst prevention about hydraulic extrusion measure was studied, the technological parameters were introduced, and the effect of outburst prevention was investigated. The in-situ experimental results show that the hydraulic extrusion measures are applied in serious outburst mine, not only the stress of stimulate outburst is eliminated effectively but also the gas in coal seam is released efficiently, the measures get obvious effect on coal and gas outburst prevention, and the roadway driving speed is increased by 1.5 times, implementing a safe and rapid excavation.

Water resources in australian mine pit lakes

In Australia and worldwide, open cut mining has become increasingly common over the last few decades through changes in excavation technology and ore economics. However, such operations frequently leave a legacy of open mine pits once mining ceases. Pit lakes will then form in mine pits that extend below the water table when dewatering operations cease. Pit lake waters are typically contaminated with metals, metalloids, saline or acidic/alkaline and rarely approach natural water body chemistry. Physically, pit lakes have unique bathymetries, are often strongly wind sheltered and have very small catchments. Nevertheless, pit lake waters often constitute a vast resource but of limited beneficial use (due to water quality issues); with a potential to contaminate regional surface and ground water resources. Water in pit lakes has the potential to be useful for a range of purposes in the Australian context of characteristic hot, dry climate and relatively few natural water bodies. Consequently, pit lakes can be seen to represent either a significant liability or a water resource to mining companies and regional communities. However, the lack of knowledge on pit lakes continues to hinder their proper management. This paper summarises the limited information currently available on water quality associated with Australian pit lakes. Information on pit lake occurrence, distribution and water quantity and quality is not nationally collated and requires immediate and ongoing attention from both mining companies and regulating authorities. Lack of a readily available database for pit lake occurrence, distribution and water quality fails to realise the potential for these water resources by both mining companies and Australian communities. Lack of access to pit lake quantity and water quality data may also lead to failure to manage this significant source of mining environmental risk.

Geomaterial Excavation in Surficial Environment

Some materials and energy needed to operate modern societies are conveyed and transmitted through lifelines that are buried in excavated trenches in the subsurface. Over a span of millennia, excavation technology for geomaterials has gone from the use of flint stones and sticks to dislodge soil to sophisticated machinery and techniques for intelligent removal of soil and rock in complex geohydrological environments. Developments in geomaterials excavation technology have also been matched by advances in analytical techniques to support mineral resource recovery, waste burial, transport of pipeborne water, oil and gas operations, geothermal energy development, large-scale civil and industrial construction, tunneling operations for mass transit, and even extraterrestrial excavation. Large-scale projects are being implemented in many countries as part of economic development programs. Energy generation and supply require the design, construction, and maintenance of buried pipelines, cables, and control stations. In early 2005, more than 83,528 km of oil and gas pipelines were under construction through various terrains globally, of which 22,873 km were in North America. For projects completed between July 1, 2004, and June 30, 2005, data obtained from the United States Federal Energy Regulatory Commission indicate that the average implementation cost per kilometer of pipeline was US$0.755 million, within an approximate range of US$0.332 million to 3.734 million. Despite the high pace of pipeline construction and the high volume of materials excavated, the exceedance of current and potential energy delivery capacity of available infrastructure by current and projected demand is a concern that has driven the initiation of many additional construction projects worldwide. For example, the European Union is expected to become dependent on external energy supplies by as much as 70% by 2030. A larger fraction of oil and gas supplies to the EU will need to be conveyed by buried pipelines that will traverse rugged and rocky terrains, as at present. Energy supply is not the sole driver of geomaterials excavation projects. Despite improvements in material recycling and the extraction efficiency of valuable minerals from excavated materials, mining and processing operations still leave behind huge quantities of tailings and other residuals. Geomaterial excavation for developing civil and industrial infrastructure is a feature of most urban areas. Construction of physical facilities, and hence excavation of geomaterials, is increasing to keep pace with high urbanization rates averaging 3% of an increasing total population in most countries.

Intelligent Cable Shovel Excavation Modeling and Simulation

Cable shovel excavators are used for primary production of geomaterials in many surface mining operations. A major problem in excavation is the variability of material diggability, resulting in varying mechanical energy input and stress loading of shovel dipper-and-tooth assembly across the working bench. This variability impacts the shovel dipper and tooth assembly in hard formations. In addition, the geometrical constraints within the working environment impose production limitations resulting in low production efficiency and high operating costs. An intelligent shovel excavation (ISE) technology has been proposed as a potential solution to these problems. This paper addresses the requirements of the dynamic models of the cable shovel underlying the ISE technology. The dynamic equations are developed using the Newton–Euler techniques. These models are validated with real-world data and simulated in a virtual prototype environment. The results provide the path trajectories, dynamic velocity and accelerat...

Mechanics of cable shovel-formation interactions in surface mining excavations

The cable shovel excavator is used for primary production in many surface mining operations. A major problem in excavation is the variability of material diggability, resulting in varying mechanical energy input and stress loading of shovel dipper-and-tooth assembly across the working bench. This variability impacts the shovel dipper and tooth assembly in hard formations. In addition, the geometrical constraints within the working environment impose production limitations resulting in low production efficiency and high operating costs. A potential solution to the above problems is the deployment of an intelligent shovel excavation (ISE) technology, with real-time formation identification, recording and knowledge transmission capabilities. This paper advances the ISE technology by developing dynamic models of the cable shovel using the Newton–Euler techniques. The models include the main factors that influence shovel performance including the effect of both linear and angular motions of dipper handle and dipper. A path trajectory is modeled to demonstrate the dynamic velocity and acceleration profiles. Numerical examples show that the critical performance variables include geometrical and physical properties of the dipper and dipper handle, digging strategies and formation properties. The kinematic results show that the critical phase occurs between 1.5 and 2.0 s of a 3-s excavation cycle with occurrence of maximum kinematic effects. The dynamic results also show a similar trend with maximum dynamic effects between 1.5 and 2.0 s. The results also show that the maximum resistive force occurs at 1.625 s within the excavation cycle. At this point the maximum breakout force of the equipment is reached and any increase in the resistive load will require further fragmentation. The results provide appropriate information for excavation planning and execution. These models form the basis for developing dynamic shovel simulators for the ISE technology.

Development of the trenchless rehabilitation process for underground pipes based on RTM

In order to overcome the disadvantages of conventional excavation technology for repairing and replacing worn-out underground pipes, various trenchless technologies have been developed and tried. But trenchless technologies so far developed have some drawbacks such as high cost and inconvenience of operation. In this study, a rehabilitation process for underground pipes has been developed using vacuum assisted resin transfer molding (VARTM) with glass fiber fabric preform to overcome the disadvantages of present trenchless technologies. For the reliable operation of the developed method, a simple method to apply pressure and vacuum to the reinforcement was devised with a flexible mold technology. From the investigation, it has been found that the developed process requires shorter operation time and lower cost with smaller and simpler operating equipments than those of the conventional trenchless technologies.

Tethered, Down-Hole-Motor Drilling system — A benefit to Mars exploration

Drilling and excavation technology will be fundamental to the exploration of the solar system and the development of scientific outposts. To date, drilling has only been conducted on the moon to the depth of a few meters and on Mars to depths measured in centimeters. But depths on the order of tens to hundreds of meters or even kilometers will be necessary for appropriate chemical and biological sampling or to reach postulated useable volumes of liquid water on Mars. Recent NASA sponsored studies on drilling technology have highlighted the benefits and probable technology path of Tethered, Down-Hole-Motor, Drilling Technology to meet future mission requirements. While demonstrations of some drilling technology has confirmed a basic readiness level for inclusion in mission planning, fundamental rock/bit interaction phenomena and cuttings transport questions could be most directly researched in the context of a deep drilling mission on earth. This paper presents the basic concept of Tethered, Down-Hole-Motor Drilling as it might be developed to work with a broad range of available basic downhole drilling equipment, along with identification of opportunities for technology “leaps”. A recent laboratory demonstration of a similar system (performed by the authors for the Jet Propulsion Laboratory) is described that included a revolutionary new bit system that drilled an 80mm diameter hole in medium strength sandstone to a depth of 2-meters at a total power consumption that is five time less than conventional drilling methods. Comparisons of recorded mass and power consumption for conventional terrestrial drilling methods are made against demonstrated laboratory data and against postulated deep drilling scenarios with Tethered, Down-Hole-Motor, Drilling. Specific experiments are recommended including instrumented testing of bit/rock interaction in various temperature regimes, hollow stem auger performance at depth, and maintaining hole stability in regolithic layers. Experiments are directly linked to their potential benefit in the design and development of new highly efficient, low mass drilling technologies for exploring the solar system.

Trenchless Repairing of Underground Pipes Using RTM Based on the Axiomatic Design Method

To overcome the problems of excavation technology for repairing damaged underground pipes, such as sewer pipes, various trenchless (excavation free or no-dig) technologies has been proposed and tried, but they have some drawbacks such as high cost and inconvenience of operation. In this study, the rehabilitation process of underground pipes with glass fiber fabric polymer composites using Resin Transfer Molding (RTM), which overcomes the problems of present trenchless technologies has been developed through the axiomatic design approach. For the reliable and faultless operation, all the problems and situations that may occur during the real construction has been taken into account at every stage of the design process. The developed process requires shorter operation time and lower cost with smaller and simpler operating equipments than conventional trenchless technologies. From the investigation, it has been found that the developed repair technology with appropriate process parameters determined by design axioms has many advantages over conventional methods.

Latest technology of underground rock cavern excavation in Japan

Four major projects with large-scale rock underground caverns are discussed in this report; two hydropower stations, one underground oil storage facility and one underground museum in Japan. The technology applied to the construction of these caverns have some unique characteristics and can be applied to various other underground uses for different purposes and applied to larger-scale underground rock caverns with different geological and in situ stress conditions. Generally, construction of an underground cavern is comprised of five major activities: geological investigation; cavern stability analysis; initial rock support design; excavation works; and redesign of rock support according to the observational construction method. Weighted factors allocated among these factors should be established based on the rock properties and the purpose of the underground cavern use, which would define the major characteristics of the construction project. This report discusses some of major characteristics of these projects in Japan.

The Excavation Technology used in the Cow Catacombs of the Sacred Animal Necropolis, North Saqqara

The Excavation Technology used in the Cow Catacombs of the Sacred Animal Necropolis, North Saqqara