Study of Soil Abrasivity and Development of a Reliable Soil Abrasivity Index

土壤磨蚀性研究和可靠土壤磨蚀性指数的开发

• 批准号: 0928757
• 负责人: Jamal Rostami
• 金额: $ 19.02万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0928757&HistoricalAwards=false
• 关键词: Study; Soil; Abrasivity; Development; Reliable

This award is funded under the American Recovery and Reinvestment Act of 2009(Public Law 111-5).Abrasivity is an important property of soil which it is often overlooked due to its less than critical impact in many applications, including construction projects. With the increased use of soft ground tunneling, the issue of tool wear and life has become very crucial since in many cases tool inspection, maintenance, and replacement is performed under pressurized conditions or so called ?hyperbaric interventions?. This is a time consuming and costly step in tunneling, and working in tunnel face under such conditions is very dangerous and risky. There is no test or index that can provide a quantitative measurement of soil abrasivity, especially as it may pertain to wear on the excavation tools. The available measures of soil abrasivity are limited to the evaluation of the Moh?s hardness of the constituent grains and minerals. In recent years, there has been some interest in this field and a few preliminary research programs for testing soil abrasiveness have commenced. These programs primarily involve application of existing rock abrasivity measurement systems such as Norwegian Abrasivity Value AV or French LCPC test to soil. There are inherent shortcomings of these test system for application in soil. They change the grain distribution of the soil, they are performed on dry samples, cannot simulate the operational conditions of the excavation face such as moisture content and stress levels, and can not include the soil conditioners and their impact on the tool wear. We will study the parameters involved in soil abrasion and its impact on cutting tools. This will include study of the actual conditions at the face of the soft ground excavation systems to be able to closely simulate the field conditions in the testing system. Simultaneously, a study of the special grades of steel and tungsten carbide commonly used in excavation tools will be performed to develop an understanding of their surface characteristics as related to wear mechanism in soil excavation. This will include specialized tribology tests to see the interaction of these materials and various soil types and constituent minerals and grains. Based on the result of these studies, an appropriate soil abrasivity testing machine will be developed. This system will go through a critical review by team members and detailed shop drawings will be produced. The device will be fabricated and will be used to perform parametric studies on various factors influencing the soil and tool interaction and wear of the cutting tool. This will include the testing of the material properties used in the device to represent the cutting tools, various speeds for propellers and peddles, different angles in the propellers to mimic the stress levels between the cutting tool and soil, testing soils in dry, wet, saturated, and at higher water pressures, and the impact of various soil types and compositions. The results will be the selection of a set of operating parameters for the testing to yield consistent, repeatable, and meaningful results to be used as soil abrasivity index.Broader Impacts: Once the testing system is established, a standard method for measurement of soil abrasivity will be introduced to complement the existing soil mechanics testing. The applications will be to predict tool life more accurately, improve tool design and material, and to objectively evaluate the impact of soil conditioning agents. There will be a multitude of additional developments linked to this index once it becomes a standard means of measuring soil abrasiveness for application in civil, mining, and petroleum as well as manufacturing sectors serving these industries. The test could also be used in development of new materials and cutting tools used on various excavation machines.

该奖项根据 2009 年美国复苏和再投资法案（公法 111-5）提供资金。磨蚀性是土壤的一个重要特性，但由于其在许多应用（包括建筑项目）中的影响不那么重要，因此经常被忽视。 随着软土隧道掘进使用的增加，工具磨损和寿命问题变得非常重要，因为在许多情况下工具检查、维护和更换是在加压条件或所谓的“高压干预”下进行的。 这是隧道掘进过程中耗时且成本高昂的步骤，并且在这种条件下在隧道掌子面工作是非常危险和有风险的。 没有测试或指数可以提供土壤磨蚀性的定量测量，特别是因为它可能与挖掘工具的磨损有关。 土壤磨蚀性的可用测量仅限于评估组成颗粒和矿物质的莫氏硬度。 近年来，人们对这一领域产生了一些兴趣，并开始了一些测试土壤磨蚀性的初步研究项目。 这些计划主要涉及现有岩石磨蚀性测量系统的应用，例如挪威磨蚀性值 AV 或法国 LCPC 土壤测试。 这些测试系统在土壤应用中存在固有的缺点。 它们改变了土壤的颗粒分布，是在干燥样品上进行的，无法模拟开挖面的操作条件，例如含水量和应力水平，并且不能包括土壤改良剂及其对工具磨损的影响。我们将研究土壤磨损所涉及的参数及其对切削刀具的影响。 这将包括研究软土地基开挖系统表面的实际条件，以便能够在测试系统中密切模拟现场条件。 同时，还将对挖掘工具中常用的特殊钢种和碳化钨进行研究，以了解其与土壤挖掘中磨损机制相关的表面特性。 这将包括专门的摩擦学测试，以观察这些材料与各种土壤类型以及矿物成分和谷物之间的相互作用。 根据这些研究的结果，将开发出合适的土壤磨蚀性试验机。 该系统将经过团队成员的严格审查，并绘制详细的施工图。 该装置将被制造并用于对影响土壤和刀具相互作用以及切削刀具磨损的各种因素进行参数研究。 这将包括测试设备中用于代表切割工具的材料特性、螺旋桨和桨叶的不同速度、螺旋桨的不同角度以模拟切割工具和土壤之间的应力水平、在干燥、潮湿、饱和，在较高的水压下，以及各种土壤类型和成分的影响。 结果将是选择一组测试操作参数，以产生一致、可重复且有意义的结果，用作土壤磨蚀性指数。更广泛的影响：一旦建立测试系统，就可以制定测量土壤磨蚀性的标准方法将被引入以补充现有的土壤力学测试。 这些应用将更准确地预测工具寿命，改进工具设计和材料，并客观评估土壤改良剂的影响。 一旦该指数成为测量土壤磨蚀性的标准方法，应用于土木、采矿、石油以及为这些行业服务的制造业，将会有许多与该指数相关的其他发展。 该测试还可用于开发各种挖掘机上使用的新材料和切削工具。