Shear Wave Velocity Measurements During Ground Improvement at a Municipal Solid Waste Landfill Site in South Carolina

作者：Clifford Astill castill@nsf.gov at注日期：5/5/98 12:15 PM优先级：Normal TO: acoles at nsf18主题：摘要：CMS-9813564， Edward Kavazanjian， GeoSyntec Consult -------------------------------消息内容-------------------------------摘要：该项目的目的是收集城市固体废物的地震反应和通过爆破致密化砂来提高地面抗液化能力的重要数据。在南卡罗莱纳多尔切斯特县的Oakridge卫生填埋场进行的爆炸诱发地面改善试点项目中，通过横波速度测量，可以同时实现这些目标，这是一个独特的机会。通过监测试验爆破引起的地面运动来测量固体废物中的横波速度，通过井间和井下测试来测量爆破前后改良地面的横波速度。这些在爆破前后对固体废物和地面的剪切波速测量将为这些材料的动态行为提供有价值的见解，并可能确定值得进一步研究的重要现象。关于城市固体废物横波速度的信息仅限于在南加州垃圾填埋场获得的数据，但它是评估整个美国垃圾填埋场地震反应的基础。相对潮湿的橡树岭垃圾填埋场的固体废物横波速度与干旱的南加州垃圾填埋场的不同，将为废物性质的区域差异提供证据。这些潜在的差异可能会对南加州以外的垃圾填埋场的抗震设计产生重大影响。最近来自一个动力固结地基改善项目的数据表明，由于侧向应力的增加，传统的渗透测试高估了诱导致密化。爆破前后的横波速度测量可以对锥贯仪阻力作为改进措施的有效性提供重要的检验，并可能提供一种更直接和更经济的方法来验证改进，并且可以为改进机制提供重要的见解。+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ 诚如Clifford j·阿斯蒂尔所说,Ph值:703-306-1362;传真：703-306-0291 castill@nsf.gov www.eng.nsf.gov/cms/castill.htm Nat'l Science Fdn 4201 Wilson Blvd。弗吉尼亚州阿灵顿545号邮编22230

Author: Clifford Astill castill@nsf.gov at NOTE Date: 5/5/98 12:15 PM Priority: Normal TO: acoles at nsf18 Subject: Abstract: CMS-9813564, Edward Kavazanjian, GeoSyntec Consult ------------------------------- Message Contents ------------------------------- Abstract: CMS-9813564, Edward Kavazanjian, GeoSyntec Consultants The objective of this project is to collect important data on the seismic response of municipal solid waste and on ground improvement to enhance liquefaction resistance through densification of sand by blasting. A unique opportunity exists to achieve these objectives simultaneously through shear wave velocity measurements during a blast-induced ground improvement pilot program at the Oakridge Sanitary Landfill in Dorchester County, South Carolina. Shear wave velocity in the solid waste is measured by monitoring ground motions induced by the test blasts, while shear wave velocity of the improved ground is measured before and after blasting using crosshole and downhole testing. These shear wave velocity measurements on the solid waste and in the ground before and after blasting will provide valuable insight into the dynamic behavior of these materials, and may identify important phenomenon that merit further investigation. Information on the shear wave velocity of municipal solid waste is limited to data obtained in southern California landfills, yet it is the basis for evaluation of the seismic response of landfills throughout the United States. Solid waste shear wave velocities at the relatively wet Oakridge Landfill that differ from those at arid southern California landfills would provide evidence of regional differences in waste properties. These potential differences could have a major impact on the seismic design of landfills outside of southern California. Recent data from a dynamic-consolidation ground-improvement project show that the induced densification was overestimated using conventional penetration testing due to increases in lateral stress. Shear wave velocity measurements before and after blasting can provide an important check on the validity of cone penetrometer resistance as a measure of improvement, and may provide a more immediate and cost-effective means of verifying improvement, and can provide important insights into the mechanisms of improvement. +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ Clifford J. Astill Ph:703-306-1362; X5083 Fax:703-306-0291 castill@nsf.gov www.eng.nsf.gov/cms/castill.htm Nat'l Science Fdn 4201 Wilson Blvd., Rm545 Arlington, VA 22230