CE$6$E$/$CE$/"$In geotechnical engineering, what are the key principles governing soil compaction techniques, and how do factors like moisture content and compaction energy affect the achieved density? Additionally, how does the Proctor compaction test contribute to understanding soil behavior under compaction efforts? Discuss the significance of achieving optimum moisture content and maximum dry density in compaction operations for ensuring the stability and longevity of civil engineering structures."

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