FALLING BALL INSPECTION METHOD AND ITS APPLICATIONS IN FILL COMPACTION CONTROL OF FILL DAMS
Quality assurance (QA) of fill material compaction plays an important role in many types of civil constructions including earth and rock dams, dikes, roads and railways. While several traditional inspection methods such as in-situ relative density measurement are currently available in engineering practice, none is suitable for testing a wide range of fill materials with greatly different particle sizes and stiffness. This paper introduces a new, rapid inspection technique based on Hertz’s theory of impact, known as Falling Ball Inspection or FBI. In this method, a rigid ball is dropped from a certain height and collides with the fill material. Through analyzing the impact process, the elastic compressive modulus of the fill material can be deduced instantaneously. This technique is shown to be extremely efficient. By taking into account the plastic deformation behavior of earth materials associated with large strains during an impact process, this new inspection method achieves greatly improved accuracy and reliability without scarifying its high efficiency. As a result, the FBI technique is particularly well suited in construction management that requires rapid and precise evaluation of the in-situ fill quality. As demonstrates in comparative experiments, the FBI technique is applicable to a wide range of fill materials from clay to granular soils, and to soil cement. An example of applying FBI method in a zoned earth-rock fill dam construction in Japan is also provided in the paper.
Rock-earth dam Earth fill Compaction Quality assurance Construction management Falling ball inspection technique
Jiaye Wu Yukiyoshi Kitamoto Jiaer Wu Masao Itoh Takeshi Ikejiri Zengwei Wu
Central Giken Co., Ltd.Hachioji, 192-0063, Tokyo, Japan Kajima CorporationChofu, 182-0036, Tokyo, Japan URS CorporationOakland, California, 94546 USA Maeda Kosen Co., LtdChuo-ku, 103-0005, Tokyo, Japan Sichuan Central Inspection Tech.Co.Zigong, Sichuan, 64300, China
国际会议
西安
英文
1-19
2005-11-01（万方平台首次上网日期，不代表论文的发表时间）