CAJ | 학술논문

南水北调中线总干渠磁县段的地基土具有中等震动液化现象，如处理不当可能导致渠道沉陷甚至滑坡，危及渠道安全。设计采用夯扩挤密碎石桩进行地基处理，为此需在现场选取有代表性的场地上进行试桩，通过试验验证不同桩间距对砂土液化的处理效果，以确定合适的桩间距，为大面积施工提供有关参数和依据。夯扩挤密碎石桩利用重锤冲击成孔，分层填入碎石或其他置换料，并夯击至设计标高。试验表明，采用桩间土标准贯入试验可判断经处理后的地基土，桩间距为1．8m时不存在液化，桩间距为1．9m时存在液化。原位跨孔剪切波速试验结果显示，处理后桩间土的剪切波速较地基处理前提高较多，证明挤密效果明显。
남수북조중선총간거자현단적지기토구유중등진동액화현상，여처리불당가능도치거도침함심지활파，위급거도안전。설계채용항확제밀쇄석장진행지기처리，위차수재현장선취유대표성적장지상진행시장，통과시험험증불동장간거대사토액화적처리효과，이학정합괄적장간거，위대면적시공제공유관삼수화의거。항확제밀쇄석장이용중추충격성공，분층전입쇄석혹기타치환료，병항격지설계표고。시험표명，채용장간토표준관입시험가판단경처리후적지기토，장간거위1．8m시불존재액화，장간거위1．9m시존재액화。원위과공전절파속시험결과현시，처리후장간토적전절파속교지기처리전제고교다，증명제밀효과명현。
Foundation soil of Ci-Xian section of the main canal in the Middle Route of South-to-North Water Transfer Project has medium liquefaction phenomenon .Canal subsidence and landslide can happen if the foundation soil is not treated properly ,which can affect canal safety .The ram-compaction gravel piles can decrease sand ground liquefaction .In-situ pile test needs to be con-ducted .The effects of different pile spacing on treatment of sand liquefaction were tested to determine the appropriate pile spac-ing ,which can support the design parameters and principle for pile construction in a large area .The ram-compaction gravel piles used heavy hammer impact to form the hole ,and then filled in gravel or other replacement materials in each layer to reach the design height .The results showed that ground liquefaction is not shown when the pile spacing is 1 .8 m but occurs when the pile spacing is 1 .9 m .In addition ,the shear wave test of original crosshole showed that the shear wave velocity of soil among piles increases after the treatment ,which indicated the compaction effect is significant .