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

作者：克利福德·阿斯蒂尔·卡斯蒂尔@nsf.gov注意日期：5/5/98 12：15 PM优先级：正常至：nsf18处Acoles主题：摘要：CMS-9813564，爱德华·卡瓦赞健，GeoSyntec咨询-摘要：CMS-9813564，爱德华·卡瓦赞健，这个项目的目标是收集关于城市固体废物的地震反应的重要数据，以及通过爆破使沙子致密以增强抗液化能力的地基加固。在南卡罗来纳州多尔切斯特县的奥克里奇卫生垃圾填埋场进行爆炸引起的地基改良试验计划期间，通过测量横波速度，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剪切波速，同时利用井间和井下测试来测量爆破前后改良地基的剪切波速。这些在爆破前后对固体废物和地面上剪切波速的测量将为了解这些材料的动力学行为提供有价值的见解，并可能发现值得进一步研究的重要现象。有关城市固体废物剪切波速的信息仅限于在南加州垃圾填埋场获得的数据，但它是评估全美垃圾填埋场地震反应的基础。在相对潮湿的橡树岭垃圾填埋场，与干旱的南加州垃圾填埋场不同的固体废物剪切波速度将提供废物性质地区差异的证据。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。强夯法地基加固工程的最新数据表明，由于侧向应力的增加，用常规的贯入试验高估了诱发的密实度。爆破前后的剪切波速测量可以为锥形贯入仪阻力作为改进措施的有效性提供重要的检验，可以提供一种更直接和更经济的手段来验证改进，并可以对改进的机理提供重要的见解。===。

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