DEVELOPMENT OF DESIGN PLAN
1.Selection of the tamper mass and drop height to correspond to the required depth of improvement.
2.Determination of the applied energy to be used over the project site to result in the desired improvement.
SELECTION OF TAMPER AND DROP HEIGHT
n has been found at project sites to range from 0.3 to 0.8. The variation in n is attributed to the: ① Efficiency of the drop mechanism of the crane. ② Total amount of energy applied. ③ Type of soil deposit being densified. ④ Presence of energy absorbing layers. ⑤ Presence of a hard layer above or below the deposit being densified. ⑥ Contact pressure of the tamper.
considerations
GRID SPACING
AND NUMBER OF DROPS
SURFACE STABILIZING
LAYER
MULTIPLE PASSES
论介文绍绪 论 研预究先背评景估 研设 究计 方考 法虑 研招 究投 结标 果程 序 问 建题 设讨 监论 管 论 文强总夯结调 整
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论介介文 绍绍绪 论 研 预预究先先背评评景估估 研设研设究计究 计方考方考法虑法虑 研招研招究投究投结标结标果程果程序序 问问建题建题设讨设讨监论监论管管 论论文文强强总总夯夯结结调调整整
1 2
3 4
Categorize soil type: (1) Site Investigation (2) General Description of Soil Categories
论介文绍绪 论 研预预究先先背评评景估估 研设 究 计 方考 法虑 研招 究投 结标 果程 序 问 建题 设讨 监论 管 论 文强总夯结调 整
APPLIED ENERGY REQUIREMENTS
AREA TO
DENSIFY
SELECTION OF
TAMPER AND
DROP HEIGHT
Design
AREA TO DENSIFY
GRID SPACING AND NUMBER OF DROPS
MULTIPLE PASSES
SURFACE STABILIZING LAYER
Dynamic compaction is generally completed over an area larger than the plan area of the embankment or the loaded area.
Assess site restraints: (1) Ground Vibrations (2) Lateral Ground Displacements (3) High Water Table (4) Presence of Hard or Soft Layers
Determine design requirements: (1) Tolerable Settlement (2) Minimum Soil Property (3) Depth Of Improvement Limitation
预先评估 设计考虑 招投标程序 建设监管 强夯调整
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The mass of the tampers generally ranges from 5.4 to 27.2 Mg, and drop heights range from 12.2to 30.5 m.
Lighter tampers and smaller drop heights result in depths of improvement on the order of 3.0 to 4.6 m. Heavier tampers and greater drop heights result in improvements on the order of 6.1 to 9.1 m
论介文绍绪 论 研预究先背评景估 研设 究计 方考 法虑 研招 究投 结标 果程 序 问 建题 设讨 监论 管 论 文强总夯结调 整 APPLIED ENERGY REQUIREMENTS
论介文绍绪 论 研预究先背评景估 研设 究计 方考 法虑 研招 究投 结标 果程 序 问 建题 设讨 监论 管 论 文强总夯结调 整
Estimate costs: (1)Dynamic Compaction Costs (2)Alternate Ground Improvement Techniques
论研介介文究 绍绍绪背 论景 研 预预究先先背评评景估估 研设 究计 方考 法虑 研招 究投 结标 果程 序 问 建题 设讨 监论 管 论 文强总夯结调 整
3.Selection of the area to densify. 4.Determination of the grid spacing and number of phases. 5.Establishing the number of passes. 6.The need for a surface stabilizing layer.
CONTENT
Introduction Preliminary evaluation Design considerations Contracig Adjustments during dynamic compaction
介绍