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Peila Daniele - One of the best experts on this subject based on the ideXlab platform.
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A new test device for the study of metal wear in conditioned granular Soil used in EPB shield tunneling
2018Co-Authors: Oñate Salazar, Cristina Gabriela, Todaro Carmine, Bosio Federico, Bassini Emilio, Ugues Daniele, Peila DanieleAbstract:The wear phenomenon evaluation in EPB shield tunneling machines is not a simple issue, as a large number of parameters are involved, such as Soil and tool material properties, Soil Conditioning and pressure in the bulk chamber. The evaluation of the influence of these parameters and predicting this influence is a complex task and the research has proposed different test procedures and approaches. In this paper a new procedure for testing wear of tools with an innovative concept and design is presented. The experimental results obtained using conventional steel and hard material tools, tested with natural and conditioned Soils, are discussed. The outcomes show the feasibility of the proposed procedure and the quality of the measurements that can be obtained using the proposed wear tool shape
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Impact of Conditioned Soil Parameters on Tool Wear in Soft Ground Tunneling
2017Co-Authors: Hedayatzadeh Mansour, Rostami Jamal, Peila DanieleAbstract:The use of mechanized shielded tunnel boring machines (TBMs), has grown rapidly in various soft ground tunneling projects. In the recent years, Earth Pressure Balance (EPB) shields have been successfully used in many tunneling projects in urban areas while the range of Soil types that it can handle has expanded. One of the critical issues for successful EPB tunneling is the use of proper Soil Conditioning. The effects of Soil abrasiveness on primary and secondary wear of tools and machine components is one of the most important aspects of soft ground tunneling, estimation and assess-ment of, costs, and schedule of a project. Among the parameters that can affect tool wear, Soil Conditioning is the most critical one that can be controlled by the operators. To assess the impact of the Soil Conditioning on tool wear, a new test apparatus with new propeller has been developed. Specific test procedure has been developed and many tests have been conducted. Review of the initial test results shows that Soil Conditioning reduces wear of tool and other machine parts. More tests are underway to evaluate the effect of Soil Conditioning on machine torque requirements through a parametric study
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Impact of Conditioned Soil Parameters on Tool Wear in Soft Ground Tunneling
2017Co-Authors: Hedayatzadeh Mansour, Rostami Jamal, Peila DanieleAbstract:The use of mechanized shielded tunnel boring machines (TBMs), has grown rapidly in various soft ground tunneling projects. In the recent years, Earth Pressure Balance (EPB) shields have been successfully used in many tunneling projects in urban areas while the range of Soil types that it can handle has expanded. One of the critical issues for successful EPB tunneling is the use of proper Soil Conditioning. The effects of Soil abrasiveness on primary and secondary wear of tools and machine components is one of the most important aspects of soft ground tunneling, estimation and assess-ment of, costs, and schedule of a project. Among the parameters that can affect tool wear, Soil Conditioning is the most critical one that can be controlled by the operators. To assess the impact of the Soil Conditioning on tool wear, a new test apparatus with new propeller has been developed. Specific test procedure has been developed and many tests have been conducted. Review of the initial test results shows that Soil Conditioning reduces wear of tool and other machine parts. More tests are underway to evaluate the effect of Soil Conditioning on machine torque requirements through a parametric study
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Undrained behaviour of granular Soils conditioned for EPB tunnelling - A new experimental procedure [Undräniertes Verhalten von grobkörnigen Böden für Vortriebe mit EPB-Schilden - Ein neues experimentelles Verfahren]
2017Co-Authors: Martinelli Daniele, Winderholler Rodrigo, Peila DanieleAbstract:This paper presents a characterisation campaign carried out on granular Soils conditioned for EPB tunnelling using a modified direct shear box. The main objective of Soil Conditioning is the reduction of its shear strength to control the counterpressure inside the bulk chamber. In order to preserve the pseudo-fluid characteristics of the conditioned Soil mass, the main concerning para meters are their undrained properties. To characterise the un drained behaviour an adopted watertight direct shear apparatus was used. The purpose of this research is to define a simplified testing procedure for conditioned Soil, analysing its feasibility and reliability with resources that can be found at any laboratory or job site. A comparison between the results obtained under dry and conditioned conditions is presented for three different cohesionless Soils. The choice of the materials studied has been made in order to cover a wide range within sands grain size
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Undrained behaviour of granular Soils conditioned for EPB tunnelling – A new experimental procedure [Undräniertes Verhalten von grobkörnigen Böden für Vortriebe mit EPB-Schilden – Ein neues experimentelles Verfahren]
2017Co-Authors: Martinelli Daniele, Winderholler Rodrigo, Peila DanieleAbstract:This paper presents a characterisation campaign carried out on granular Soils conditioned for EPB tunnelling using a modified direct shear box. The main objective of Soil Conditioning is the reduction of its shear strength to control the counterpressure inside the bulk chamber. In order to preserve the pseudo-fluid characteristics of the conditioned Soil mass, the main concerning para meters are their undrained properties. To characterise the un drained behaviour an adopted watertight direct shear apparatus was used. The purpose of this research is to define a simplified testing procedure for conditioned Soil, analysing its feasibility and reliability with resources that can be found at any laboratory or job site. A comparison between the results obtained under dry and conditioned conditions is presented for three different cohesionless Soils. The choice of the materials studied has been made in order to cover a wide range within sands grain size
Daniele Peila - One of the best experts on this subject based on the ideXlab platform.
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development of a Soil abrasion test and analysis of impact of Soil Conditioning on tool wear for soft ground mechanized tunneling using epb machines
2017Co-Authors: Mansour Hedayatzadeh, Daniele Peila, Jamal Rostami, Omid Forough, Onate Salazar, Cristina GabrielaAbstract:a (*),Omid Forough(**), Cristina Gabriela Onate Salazar(*) (*) Politecnico di Torino (Italy), colorado school of mines (USA) A. B. Unknown Affiliation, City, Country. In the recent years, Earth Pressure Balance (EPB) shields have been successfully used in many tunnels in urban areas. One of the critical issues for successful EPB tunneling is the use of proper Soil Conditioning to reduce wear and torque. Among the parameters that can affect tool wear, Soil Conditioning is the most important one that can be controlled by the operators. Soil Conditioning has been used to improve the performance of tunneling machines and to expand their area of application and is mostly done by adding various foaming agent. To assess the impact of the Soil Conditioning on tool wear, specific laboratory scale test was developed. Review of the initial test results shows that with using Soil Conditioning, the wear of tool can reduce. The results also show that agents can be designed to offer optimum performance for a target ambient pressure.
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Laboratory tests on Soil Conditioning of clayey Soil
2016Co-Authors: Daniele Peila, Andrea Picchio, D. Martinelli, E. Dal NegroAbstract:Tunnelling in difficult and challenging conditions such as soft Soils in urban areas is increasing. In this condition, it is important to minimise the possible negative effect of the tunnel excavation, such as settlement or, in the worst case, collapses. To achieve this result, earth pressure balance machines are commonly used. One of the key parameters that must be considered for an optimal management of the EPB-TBM excavation is Soil Conditioning since the excavated muck must properly transmit the pressure to the tunnel face. Soil Conditioning is also necessary to reduce the effect of the problems, such as clogging in clay layers, that can occur during the excavation and that can affect the performance of the tools and of the entire tunnelling process. For this reason, in the last decade, much research has been carried out to understand how to deal with and reduce the effects of clogging and stickiness, using different Conditioning additives. These studies have proposed several different test procedures to evaluate the effect of the Conditioning on the adhesion of the Soil on the metallic parts of the machines. The present research has been carried out with the aim of proposing a new approach and new devices to study clay Conditioning with laboratory tests, and the results of many tests carried out with the proposed device are presented and discussed.
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earth pressure balance tunnelling in rock masses laboratory feasibility study of the Conditioning process
2013Co-Authors: Daniele Peila, Andrea Picchio, Alessio ChieregatoAbstract:Abstract Earth pressure balance (EPB) shield tunnelling is considered to be an effective tunnelling method when surface settlements must be avoided by controlling face stability and underground water inflow. EPB technology is applied increasingly to the Conditioning of rock masses in which the presence of polluting material is foreseen and must be controlled, or when explosive gases from the rock mass must be prevented from entering in the machine. The use of an EPB machine in ‘closed mode’ can prevent the dispersion of dangerous materials in the underground environment. This study was performed to evaluate the feasibility of using EPB technology in rock masses and the effectiveness of this tunnelling process in terms of Soil Conditioning, conditioned Soil permeability, pressure transmission on the tunnel face, and the ability to extract the material with a screw conveyor. The research was developed with a set of laboratory tests carried out on three different types of rock masses where tunnelling with EPB machines are planned to be constructed in Italy but the results can be easily applied to similar rock mass types. The tests have been carried out both with slump tests and with a specially constructed screw conveyor extraction device. In the paper the most important results are presented and discussed.
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Soil Conditioning for epb shield tunnelling
2013Co-Authors: Daniele PeilaAbstract:The use of Conditioning agents that change the mechanical and hydraulic behavior of a cohesionless Soil into an impervious and plastic paste is the key point for the correct management of EPB (Earth Pressure Balance) shield tunneling. The design of Soil Conditioning sets and the choice of the best products to be used require special laboratory tests. These tests should be carried out already at the design stage to allow to check if the needed results can be achieved in the Soil to be excavated. In the paper an overview of the different type of laboratory tests that can be used on cohesionless Soils are presented and the most important results that can be obtained are discussed.
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Soil Conditioning for EPBMs
2008Co-Authors: Raffaele Vinai, Daniele Peila, Luca Borio, Claudio Oggeri, Sebastiano PelizzaAbstract:Raffaele Vinai, Luca Borio, Daniele Peila, Claudio Oggeri and Sebastiano Pelizza, of the Department of Land, Environment and Geo-engineering, Tunnelling and Underground Space Centre; Politecnico di Torino (Italy) discuss recent research into Soil Conditioning for EPBMs.
Mark Van Kleunen - One of the best experts on this subject based on the ideXlab platform.
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Soil microorganism mediated invasional meltdown in plants
2020Co-Authors: Zhijie Zhang, Yanjie Liu, Caroline Brunel, Mark Van KleunenAbstract:While most alien species fail to establish, some invade native communities and become widespread. Our understanding of invasion success is derived mainly from pairwise interactions between aliens and natives, while interactions among more than two species remain largely unexplored. Here, we experimentally tested whether and how a third plant species, either native or alien, affected the competitive outcomes between alien and native plants through its Soil legacy. We first conditioned Soil with one of ten species (six natives and four aliens) or without plants. We then grew on these 11 Soils five aliens and five natives without competition, or with intra- or interspecific competition. We found that aliens were not more competitive than natives when grown on Soil conditioned by other natives or on non-conditioned Soil. However, aliens were more competitive than natives on Soil conditioned by other aliens (that is, invasional meltdown). Soil Conditioning did not change competitive outcomes by affecting the strength of competition between later plants. Instead, Soil conditioned by aliens pushed competitive outcomes towards later aliens by affecting the growth of aliens less negatively than that of natives. Microbiome analysis verified this finding, as we showed that the Soil-legacy effects of a species on later species were less negative when their fungal endophyte communities were less similar, and that fungal endophyte communities were less similar between two aliens than between aliens and natives. Our study reveals invasional meltdown in multispecies communities and identifies Soil microorganisms as a driver of the invasion success of alien plants.
Martijn T Bezemer - One of the best experts on this subject based on the ideXlab platform.
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plant community evenness responds to spatial plant Soil feedback heterogeneity primarily through the diversity of Soil Conditioning
2018Co-Authors: E Jasper R Wubs, Martijn T BezemerAbstract:1.Plant-Soil feedback (PSF) has been identified as a key driver of local plant diversity and evenness in competitive communities. However, while it has been shown that spatial PSF heterogeneity can alter plant performance and competitive interactions, there is no proof of principle that spatial PSF heterogeneity enhances community diversity. 2.Using a grassland model system we separated two aspects of spatial heterogeneity: the number of species Conditioning the Soil and spatial distribution of the PSFs. 3.Our data show that PSFs promoted a higher plant evenness when the Soil was conditioned by multiple species (mixed-conditioned), then when the Soil was conditioned by a single species (mono-conditioned). On mono-conditioned Soils, heterospecifics typically outperformed the focal species. In addition, there was a trend for increasing community evenness from uniform, via fine-grained to coarse-grained mixed-conditioned Soils, but this was not significant. 4.On mixed-conditioned Soils, performance of all competing species was intermediate to the best and the worst mono-conditioned Soils, leading to higher community evenness. 5.Our data demonstrate that PSFs play a role in promoting plant evenness. Across mono-conditioned Soils, PSF led to altered competitive hierarchies. However, on Soils conditioned by multiple species, competitive ability among species was more similar and this led to higher plant evenness. The spatial distribution of the heterogeneity, on the other hand, did not significantly affect plant evenness. Our data therefore show that community evenness was more strongly related to the number of plant species that conditioned the Soil than the spatial distribution of the PSF heterogeneity. Future studies need to investigate the importance of PSFs in the field across plant life-stages and multiple generations.
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plant Soil feedback effects on plant quality and performance of an aboveground herbivore interact with fertilisation
2015Co-Authors: Martine Kos, Patrick P.j. Mulder, J. Roo, Maarten A B Tuijl, Martijn T BezemerAbstract:Plant–Soil feedback (PSF) effects on plant performance can be influenced by the availability of nutrients in the Soil. Recent studies have shown that PSF effects can also change aboveground plant–insect interactions via Soil-mediated changes in plant quality, but whether this is influenced by Soil nutrient availability is unknown. We examined how fertilisation influences PSF effects on aboveground plant-aphid interactions in ragwort Jacobaea vulgaris. We grew J. vulgaris in Soil conditioned by conspecific plants and in unconditioned Soil at two levels of fertilisation and measured Soil fungal communities, plant biomass, concentrations of primary (amino acids) and secondary (pyrrolizidine alkaloids; PAs) metabolites in phloem exudates, performance of the specialist aphid Aphis jacobaeae and sequestration of PAs by the aphid. We observed a strong interaction between Soil Conditioning and fertilisation on amino acid and PA concentrations in phloem exudates of J. vulgaris and on aphid performance, with opposite effects of Soil Conditioning at the two fertilisation levels. Plant biomass was reduced by Soil Conditioning and increased by fertilisation. Aphids contained high PA concentrations, converted N-oxides into tertiary amines and preferentially sequestered certain PA compounds, but PA sequestration was not affected by any of the treatments. We conclude that effects of PSF and fertilisation on plant chemistry and aphid performance are interdependent. Our study highlights the need to consider the importance of abiotic Soil conditions on the outcome of PSF effects on aboveground plant–insect interactions.
Sheri C. Huerd - One of the best experts on this subject based on the ideXlab platform.
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Soil Conditioning affects interactions between native and invasive exotic perennials of semi natural grasslands
2017Co-Authors: Stefanie N Vink, Nicholas R. Jordan, Sheri C. Huerd, Laura Aldrichwolfe, Craig C Sheaffer, Linda L KinkelAbstract:Summary 1.Semi-natural perennial grasslands are of increasing importance as components of multifunctional agroecosystems, combining biomass production with provision of other ecosystem services. Soil legacies from previous land use or exotic species can hinder their establishment, but might be overcome through a multi-stage successional strategy, whereby certain species are used to facilitate native grassland species establishment. We tested this strategy via a feedback experiment examining Soil Conditioning effects on interference interactions between native and exotic species. 2.Soils in a former maize–soybean production field in Minnesota, USA, were conditioned for three years with native or invasive exotic perennials or a maize–soybean crop rotation. Nitrogen (N) fertilisation was an additional treatment in field plots. In a greenhouse, native and invasive exotic perennial grassland seedlings were grown on these Soils, in monoculture and in native–exotic species pairs, with and without N fertilisation. The impact of Soil Conditioning and field and greenhouse N fertilisation on interactions between native and exotic seedlings in mixture was determined. 3.Neighbouring plants suppressed biomass production in all native and exotic species. The maize–soybean rotation left a Soil legacy that enhanced suppression of native species when grown with exotic species, while exotic species suffered no such disadvantage. 4.The strong and specific disadvantage to native species of maize–soybean Soils decreased with greenhouse N fertilisation, but remained significant, while field N addition did not alter this effect. 5.Synthesis and applications. We found that the negative Soil legacy of the maize–soybean rotation for native plant performance in interaction with exotics was greatly diminished in Soils conditioned by native or exotic perennial species, irrespective of nitrogen addition. This highlights the potential value of perennial species in conversion from row-crop agriculture to grasslands, because all perennial species alleviated the enhanced suppression of natives observed on maize–soybean Soils. We did not find strong evidence that these perennial species were capable of specifically facilitating native species over exotics, but a broader range of species should be evaluated. This article is protected by copyright. All rights reserved.
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Soil Conditioning effects of native and exotic grassland perennials on the establishment of native and exotic plants
2015Co-Authors: Stefanie N Vink, Nicholas R. Jordan, Sheri C. Huerd, Linda L Kinkel, Craig C Shaeffer, Laura AldrichwolfeAbstract:Semi-natural grasslands can combine biomass production with provision of multiple ecosystem services. Unfortunately, grassland establishment can be unpredictable and vulnerable to exotic plant invasion, potentially due to Soil legacies from previous cultivation. Native plants could mitigate these legacies by changing Soil attributes and facilitating other native grassland species. However, facilitation may be affected by nitrogen (N) fertilization, added during and after establishment. We conditioned Soils in a former maize-soybean field for 3 years using multiple native or exotic perennial species or a maize-soybean rotation. Half of each plot received N fertilizer. Native and exotic grassland perennials were grown on these conditioned Soils in the greenhouse, with N added to half of the pots, and biomass was measured. Consistent facilitation of native species by other natives was not observed, nor did invasive species facilitate other invasives. Soil Conditioning affected individual plant species’ biomass in several instances. Field N addition had little effect on plant biomass, while greenhouse N addition increased native more than exotic plant biomass, but did not alter the overall pattern of facilitation. Native plants failed to facilitate native prairie establishment in this work, suggesting resistance to Conditioning on former intensive, high-input agricultural Soils.
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Soil Conditioning effects of native and exotic grassland perennials on the establishment of native and exotic plants
2015Co-Authors: Stefanie N Vink, Nicholas R. Jordan, Sheri C. Huerd, Linda L Kinkel, Craig C Shaeffer, Laura AldrichwolfeAbstract:Background and Aims Semi-natural grasslands can combine biomass production with provision of multiple ecosystem services. Unfortunately, grassland establishment can be unpredictable and vulnerable to exotic plant invasion, potentially due to Soil legacies from previous cultivation. Native plants could mitigate these legacies by changing Soil attributes and facilitating other native grassland species. However, facilitation may be affected by nitrogen (N) fertilization, added during and after establishment.
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Soil modification by invasive plants effects on native and invasive species of mixed grass prairies
2008Co-Authors: Nicholas R. Jordan, Diane L Larson, Sheri C. HuerdAbstract:Invasive plants are capable of modifying attributes of Soil to facilitate further invasion by conspecifics and other invasive species. We assessed this capability in three important plant invaders of grasslands in the Great Plains region of North America: leafy spurge (Euphorbia esula), smooth brome (Bromus inermis) and crested wheatgrass (Agropyron cristatum). In a glasshouse, these three invasives or a group of native species were grown separately through three cycles of growth and Soil Conditioning in both steam-pasteurized and non-pasteurized Soils, after which we assessed seedling growth in these Soils. Two of the three invasive species, Bromus and Agropyron, exhibited significant self-facilitation via Soil modification. Bromus and Agropyron also had significant facilitative effects on other invasives via Soil modification, while Euphorbia had significant antagonistic effects on the other invasives. Both Agropyron and Euphorbia consistently suppressed growth of two of three native forbs, while three native grasses were generally less affected. Almost all intra- and interspecific effects of invasive Soil Conditioning were dependent upon presence of Soil biota from field sites where these species were successful invaders. Overall, these results suggest that that invasive modification of Soil microbiota can facilitate plant invasion directly or via ‘cross-facilitation’ of other invasive species, and moreover has potential to impede restoration of native communities after removal of an invasive species. However, certain native species that are relatively insensitive to altered Soil biota (as we observed in the case of the forb Linum lewisii and the native grasses), may be valuable as ‘nurse’species in restoration efforts.
