The Experts below are selected from a list of 9345 Experts worldwide ranked by ideXlab platform
John J. Bowders - One of the best experts on this subject based on the ideXlab platform.
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Slope Stabilization Using Recycled Plastic Pins – Phase III
2007Co-Authors: J. Erik Loehr, John J. BowdersAbstract:A new technique for stabilizing surficial slope failures using Recycled Plastic reinforcing members has been developed. The objective of the project described in this report has been to develop, evaluate, and document a technique for stabilization of surficial slope failures using Recycled Plastic reinforcing members. The project has been undertaken in three sequential phases to provide for logical evaluation of project accomplishments and refinement of the scope of work based on results of activities undertaken throughout the project. This report is the final technical report for the entire three phase project, which describes the accumulated activities performed throughout all three phases of the project. The principal project tasks undertaken include development of a general design methodology, evaluation of the material properties of Recycled Plastic members from several different manufacturers, establishment of full-scale field test sections at five different sites, monitoring the performance of these sites for periods ranging from two to five years, evaluation and interpretation of field observations, “calibration” of the developed design method, and finally, development of technology transfer materials. The following conclusions are drawn from the work performed as part of this project: (1) the technique of using Recycled Plastic reinforcement to stabilize surficial slope failures has proven to be effective at providing long-term stabilization; (2) observed performance at the test sites suggests a typical behavioral pattern consisting of an initial period in which little movement is observed and little load is transferred to the reinforcement, a period of increasing movement and increasing mobilized loads in the reinforcement, followed by a period of stabilized movements and loads in the reinforcing members as a result of the slope coming to equilibrium; (3) while the required member spacing depends on the conditions present at a site, a “standard” pattern that appears sufficient for most sites consists of using Recycled Plastic reinforcing members placed in a 3-ft by 3-ft (0.9-m by 0.9-m) staggered arrangement over the entire slide area; (4) reliable installation can be accomplished with either a percussion hammer similar to what is used on many drill rigs, or a simple drop-weight hammer similar to what is used to install guard rail posts; (5) care must be used when selecting Recycled Plastic products for use in slope stabilization applications as the properties of these materials can vary substantially from product to product; and (6) costs for the technique vary with the reinforcement pattern selected but appear to be substantially less than those for most other competing slope stabilization technologies.
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Stabilization of Surficial Slides Using Recycled Plastic Reinforcement
Transportation Research Record, 2007Co-Authors: J. Erik Loehr, Thomas W. Fennessey, John J. BowdersAbstract:Surficial slope failures, or nuisance slides, constitute a significant economic and manpower burden for many transportation agencies because of the frequent and recurring nature of the slides. TRB recently estimated that annual costs for stabilization of nuisance slides exceed the costs for repair of major landslides; this estimate suggests that annual costs for repair of nuisance slides on the National Highway System alone exceed $100 million. Recent work has shown the feasibility of using slender Recycled Plastic members for in situ reinforcement of surficial slides in slopes and embankments. This paper describes the activities performed to evaluate the technique and the results and conclusions derived from the work. Topics covered include the description of five instrumented field test sites, material properties of the Recycled Plastic members used, construction equipment and techniques used to install the members, general performance observed at the field test sites, and the costs of the technique as ...
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Field Performance of Embankments Stabilized with Recycled Plastic Reinforcement
Transportation Research Record, 2003Co-Authors: Jorge R. Parra, David Hagemeyer, J. Erik Loehr, John J. BowdersAbstract:The performance of earth slopes reinforced with arrays of slender reinforcing members is currently being investigated. The reinforcing members used are fabricated from Recycled Plastics and other waste materials to form sections 90 mm (3.5 in.) x 90 mm (3.5 in.) x 2.4 m (8 ft) long. A design methodology was adopted to estimate the limit resistance provided by each member, which is then incorporated into conventional limit equilibrium slope stability analyses to calculate the improvement in the factor of safety under various reinforcement scenarios. Four field test sites were stabilized using Recycled Plastic reinforcement to demonstrate the effectiveness of the stabilization scheme and to evaluate the load transfer mechanisms between the soil and the reinforcement. One additional site was stabilized with similarly sized steel pipe members for comparison with the Recycled Plastic members. The stabilized slopes are performing well, whereas several control sections have experienced failures. The performance of each site is being monitored with field instrumentation to monitor lateral movements, pore pressures, strains within the reinforcing members, and the lateral loads applied to the members. Observations to date indicate that the slopes are performing well and that the reinforcing members have significant remaining capacity to maintain the stability of the slopes.
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ENGINEERING PROPERTIES OF Recycled Plastic PINS FOR SLOPE STABILIZATION
Transportation Research Record, 2003Co-Authors: John J. Bowders, Hani A. Salim, J. Erik Loehr, Cheng-wei ChenAbstract:An ongoing demonstration project has shown the feasibility of using slender (90 mm x 90 mm x 2.4 m) Recycled Plastic pins (RPPs) for in situ reinforcement of slopes and embankments. The technique uses RPPs driven into the face of the slope in a grid pattern to intercept the sliding surface and pin the slope. The engineering properties of the RPPs, including the compressive, tensile, and flexural strength along with creep behavior, dictate the design and construction practice. Constituent materials and manufacturing processes are highly variable among the more than 30 U.S. manufacturers. A specification for acceptance of the members is needed; however, before an effective specification can be developed, the appropriate engineering properties and design requirements for the RPPs must be determined. The engineering properties and driving performance of four different types of members were evaluated and are reported on. Additional evaluations are under way.
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Construction Methods for Slope Stabilization with Recycled Plastic Pins
2000Co-Authors: Lee Sommers, J. Erik Loehr, John J. BowdersAbstract:A new method for reinforcement of surficial slope failures is currently being developed that utilizes reinforcing elements, similar to soil nails, manufactured from Recycled Plastics and other waste materials. Using Recycled Plastics has the advantage of providing reinforcing members with high resistance to degradation while providing a market for materials that might otherwise be landfilled. A key aspect of development of the new stabilization scheme is development and evaluation of equipment and methods for installing the Plastic reinforcing members. In this paper, results of a series of laboratory and field tests performed to evaluate alternative installation techniques are presented and installation activities performed to construct a full-scale field demonstration are described. Results of development activities to date indicate that Recycled Plastic members can be reliably and efficiently installed to produce a cost-effective alternative to more conventional slope stabilization techniques. Evaluation of the suitability of Recycled Plastic pin stabilization schemes for effecting long-term stabilization is ongoing.
J. Erik Loehr - One of the best experts on this subject based on the ideXlab platform.
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Slope Stabilization Using Recycled Plastic Pins – Phase III
2007Co-Authors: J. Erik Loehr, John J. BowdersAbstract:A new technique for stabilizing surficial slope failures using Recycled Plastic reinforcing members has been developed. The objective of the project described in this report has been to develop, evaluate, and document a technique for stabilization of surficial slope failures using Recycled Plastic reinforcing members. The project has been undertaken in three sequential phases to provide for logical evaluation of project accomplishments and refinement of the scope of work based on results of activities undertaken throughout the project. This report is the final technical report for the entire three phase project, which describes the accumulated activities performed throughout all three phases of the project. The principal project tasks undertaken include development of a general design methodology, evaluation of the material properties of Recycled Plastic members from several different manufacturers, establishment of full-scale field test sections at five different sites, monitoring the performance of these sites for periods ranging from two to five years, evaluation and interpretation of field observations, “calibration” of the developed design method, and finally, development of technology transfer materials. The following conclusions are drawn from the work performed as part of this project: (1) the technique of using Recycled Plastic reinforcement to stabilize surficial slope failures has proven to be effective at providing long-term stabilization; (2) observed performance at the test sites suggests a typical behavioral pattern consisting of an initial period in which little movement is observed and little load is transferred to the reinforcement, a period of increasing movement and increasing mobilized loads in the reinforcement, followed by a period of stabilized movements and loads in the reinforcing members as a result of the slope coming to equilibrium; (3) while the required member spacing depends on the conditions present at a site, a “standard” pattern that appears sufficient for most sites consists of using Recycled Plastic reinforcing members placed in a 3-ft by 3-ft (0.9-m by 0.9-m) staggered arrangement over the entire slide area; (4) reliable installation can be accomplished with either a percussion hammer similar to what is used on many drill rigs, or a simple drop-weight hammer similar to what is used to install guard rail posts; (5) care must be used when selecting Recycled Plastic products for use in slope stabilization applications as the properties of these materials can vary substantially from product to product; and (6) costs for the technique vary with the reinforcement pattern selected but appear to be substantially less than those for most other competing slope stabilization technologies.
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Stabilization of Surficial Slides Using Recycled Plastic Reinforcement
Transportation Research Record, 2007Co-Authors: J. Erik Loehr, Thomas W. Fennessey, John J. BowdersAbstract:Surficial slope failures, or nuisance slides, constitute a significant economic and manpower burden for many transportation agencies because of the frequent and recurring nature of the slides. TRB recently estimated that annual costs for stabilization of nuisance slides exceed the costs for repair of major landslides; this estimate suggests that annual costs for repair of nuisance slides on the National Highway System alone exceed $100 million. Recent work has shown the feasibility of using slender Recycled Plastic members for in situ reinforcement of surficial slides in slopes and embankments. This paper describes the activities performed to evaluate the technique and the results and conclusions derived from the work. Topics covered include the description of five instrumented field test sites, material properties of the Recycled Plastic members used, construction equipment and techniques used to install the members, general performance observed at the field test sites, and the costs of the technique as ...
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Field Performance of Embankments Stabilized with Recycled Plastic Reinforcement
Transportation Research Record, 2003Co-Authors: Jorge R. Parra, David Hagemeyer, J. Erik Loehr, John J. BowdersAbstract:The performance of earth slopes reinforced with arrays of slender reinforcing members is currently being investigated. The reinforcing members used are fabricated from Recycled Plastics and other waste materials to form sections 90 mm (3.5 in.) x 90 mm (3.5 in.) x 2.4 m (8 ft) long. A design methodology was adopted to estimate the limit resistance provided by each member, which is then incorporated into conventional limit equilibrium slope stability analyses to calculate the improvement in the factor of safety under various reinforcement scenarios. Four field test sites were stabilized using Recycled Plastic reinforcement to demonstrate the effectiveness of the stabilization scheme and to evaluate the load transfer mechanisms between the soil and the reinforcement. One additional site was stabilized with similarly sized steel pipe members for comparison with the Recycled Plastic members. The stabilized slopes are performing well, whereas several control sections have experienced failures. The performance of each site is being monitored with field instrumentation to monitor lateral movements, pore pressures, strains within the reinforcing members, and the lateral loads applied to the members. Observations to date indicate that the slopes are performing well and that the reinforcing members have significant remaining capacity to maintain the stability of the slopes.
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ENGINEERING PROPERTIES OF Recycled Plastic PINS FOR SLOPE STABILIZATION
Transportation Research Record, 2003Co-Authors: John J. Bowders, Hani A. Salim, J. Erik Loehr, Cheng-wei ChenAbstract:An ongoing demonstration project has shown the feasibility of using slender (90 mm x 90 mm x 2.4 m) Recycled Plastic pins (RPPs) for in situ reinforcement of slopes and embankments. The technique uses RPPs driven into the face of the slope in a grid pattern to intercept the sliding surface and pin the slope. The engineering properties of the RPPs, including the compressive, tensile, and flexural strength along with creep behavior, dictate the design and construction practice. Constituent materials and manufacturing processes are highly variable among the more than 30 U.S. manufacturers. A specification for acceptance of the members is needed; however, before an effective specification can be developed, the appropriate engineering properties and design requirements for the RPPs must be determined. The engineering properties and driving performance of four different types of members were evaluated and are reported on. Additional evaluations are under way.
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Construction Methods for Slope Stabilization with Recycled Plastic Pins
2000Co-Authors: Lee Sommers, J. Erik Loehr, John J. BowdersAbstract:A new method for reinforcement of surficial slope failures is currently being developed that utilizes reinforcing elements, similar to soil nails, manufactured from Recycled Plastics and other waste materials. Using Recycled Plastics has the advantage of providing reinforcing members with high resistance to degradation while providing a market for materials that might otherwise be landfilled. A key aspect of development of the new stabilization scheme is development and evaluation of equipment and methods for installing the Plastic reinforcing members. In this paper, results of a series of laboratory and field tests performed to evaluate alternative installation techniques are presented and installation activities performed to construct a full-scale field demonstration are described. Results of development activities to date indicate that Recycled Plastic members can be reliably and efficiently installed to produce a cost-effective alternative to more conventional slope stabilization techniques. Evaluation of the suitability of Recycled Plastic pin stabilization schemes for effecting long-term stabilization is ongoing.
Ss Kamaruddin - One of the best experts on this subject based on the ideXlab platform.
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Investigating the Effects of Injection Molding Parameters on the Mechanical Properties of Recycled Plastic Parts Using the Taguchi Method
Materials and Manufacturing Processes, 2011Co-Authors: Nik Mizamzul N.m. Mehat, Ss KamaruddinAbstract:The growing amount of Plastic parts produced nowadays makes the search for alternatives in recycling and the further use of these nonbiodegradable materials imperative. The degradation of the mechanical properties of Recycled Plastic products poses the primary limitation for the usage of Recycled Plastic. One of the foremost causes of mechanical property degradation is variation in processing parameters. An appropriate optimization method that effectively controls all influential processing parameters during manufacturing is therefore critical. This study investigates the effects of injection molding parameters on the mechanical properties of Recycled Plastic parts. The preliminary experiment is conducted by using Moldflow Plastic Insight (MPI) integrated with the L18 Taguchi orthogonal array (OA). The significant processing parameters obtained from the preliminary experiment were used to conduct the principal experiment. By adopting L9 Taguchi OA, the parts made from Recycled Plastic were produced by inj...
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Optimization of mechanical properties of Recycled Plastic products via optimal processing parameters using the Taguchi method
Journal of Materials Processing Technology, 2011Co-Authors: Nik Mizamzul N.m. Mehat, Ss KamaruddinAbstract:The large amount of Plastic products presently produced necessitates recycling and reuse of these non-biodegradable materials. However, the degradation in the mechanical properties of products made from Recycled Plastic is a major drawback that limits their use. This study aims to improve the mechanical properties of products made from Recycled Plastic by utilizing the Taguchi optimization method, instead of coupling the products with additives. By adopting L9 Taguchi OA, products made from various compositions of virgin and Recycled Plastic are produced by injection moulding. Four controllable factors (i.e., melt temperature, packing pressure, injection time, and packing time), each at three levels, are tested to determine the optimal combination of factors and levels in the manufacturing process. By determining the optimal combination of factors and levels, the appropriate blending ratio of virgin and Recycled Plastic can be evaluated from the mechanical performance exhibited by the compound. The effects of the optimal processing parameters and the addition of Recycled Plastic in various compositions on the mechanical properties and melt flow index of the produced parts are also investigated. The results reveal that the product made of 25% Recycled polypropylene (PP) and 75% virgin PP exhibits a better flexural modulus compared to the virgin form. The same product exhibits a 3.4% decrease in flexural strength. The degradation in mechanical properties of products produced from Recycled Plastic can be improved by optimizing the influence processing parameters during the manufacturing process.
Cheng-wei Chen - One of the best experts on this subject based on the ideXlab platform.
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ENGINEERING PROPERTIES OF Recycled Plastic PINS FOR SLOPE STABILIZATION
Transportation Research Record, 2003Co-Authors: John J. Bowders, Hani A. Salim, J. Erik Loehr, Cheng-wei ChenAbstract:An ongoing demonstration project has shown the feasibility of using slender (90 mm x 90 mm x 2.4 m) Recycled Plastic pins (RPPs) for in situ reinforcement of slopes and embankments. The technique uses RPPs driven into the face of the slope in a grid pattern to intercept the sliding surface and pin the slope. The engineering properties of the RPPs, including the compressive, tensile, and flexural strength along with creep behavior, dictate the design and construction practice. Constituent materials and manufacturing processes are highly variable among the more than 30 U.S. manufacturers. A specification for acceptance of the members is needed; however, before an effective specification can be developed, the appropriate engineering properties and design requirements for the RPPs must be determined. The engineering properties and driving performance of four different types of members were evaluated and are reported on. Additional evaluations are under way.
Nik Mizamzul N.m. Mehat - One of the best experts on this subject based on the ideXlab platform.
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Investigating the Effects of Injection Molding Parameters on the Mechanical Properties of Recycled Plastic Parts Using the Taguchi Method
Materials and Manufacturing Processes, 2011Co-Authors: Nik Mizamzul N.m. Mehat, Ss KamaruddinAbstract:The growing amount of Plastic parts produced nowadays makes the search for alternatives in recycling and the further use of these nonbiodegradable materials imperative. The degradation of the mechanical properties of Recycled Plastic products poses the primary limitation for the usage of Recycled Plastic. One of the foremost causes of mechanical property degradation is variation in processing parameters. An appropriate optimization method that effectively controls all influential processing parameters during manufacturing is therefore critical. This study investigates the effects of injection molding parameters on the mechanical properties of Recycled Plastic parts. The preliminary experiment is conducted by using Moldflow Plastic Insight (MPI) integrated with the L18 Taguchi orthogonal array (OA). The significant processing parameters obtained from the preliminary experiment were used to conduct the principal experiment. By adopting L9 Taguchi OA, the parts made from Recycled Plastic were produced by inj...
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Optimization of mechanical properties of Recycled Plastic products via optimal processing parameters using the Taguchi method
Journal of Materials Processing Technology, 2011Co-Authors: Nik Mizamzul N.m. Mehat, Ss KamaruddinAbstract:The large amount of Plastic products presently produced necessitates recycling and reuse of these non-biodegradable materials. However, the degradation in the mechanical properties of products made from Recycled Plastic is a major drawback that limits their use. This study aims to improve the mechanical properties of products made from Recycled Plastic by utilizing the Taguchi optimization method, instead of coupling the products with additives. By adopting L9 Taguchi OA, products made from various compositions of virgin and Recycled Plastic are produced by injection moulding. Four controllable factors (i.e., melt temperature, packing pressure, injection time, and packing time), each at three levels, are tested to determine the optimal combination of factors and levels in the manufacturing process. By determining the optimal combination of factors and levels, the appropriate blending ratio of virgin and Recycled Plastic can be evaluated from the mechanical performance exhibited by the compound. The effects of the optimal processing parameters and the addition of Recycled Plastic in various compositions on the mechanical properties and melt flow index of the produced parts are also investigated. The results reveal that the product made of 25% Recycled polypropylene (PP) and 75% virgin PP exhibits a better flexural modulus compared to the virgin form. The same product exhibits a 3.4% decrease in flexural strength. The degradation in mechanical properties of products produced from Recycled Plastic can be improved by optimizing the influence processing parameters during the manufacturing process.