地工格網橫向肋條剛性與間距對拉出行為之影響

The Effects of Geogrid Transverse Ribs Rigidity and Spacing on Pullout Behavior

白子興

指導教授 ： 謝啟萬

國立屏東科技大學/工學院/土木工程系所/碩士(2012年)

https://doi.org/10.6346/NPUST.2012.00285

摘要

地工格網引進台灣大約是在1980年後期，前人在生產、使用及各項試驗方面之數據已累積近30年之經驗，惟針對橫向肋條剛性對拉出行為所造成之影響仍未見詳細之試驗文獻。故本文特針對此點選用開口近方形之針織PET格網，單肋縱向強度為155.59kN/M，網目尺寸介於20～40mm間，開孔率介於50%～60%間，與石英砂、三分石等相對乾密度為80%之土壤，並採用25、50及75kPa等三種不同之正向應力，進行拉出行為之研究。分析地工格網橫向肋條材質對拉出行為之影響，提供工程界作為使用之參考。
研究結果顯示在較高圍壓之情況下，剛性橫向肋條可提供受力面垂直方向較小之變形量，進而降低橫桿干擾效應，故可提升靜摩擦階段之磨擦係數及拉出阻抗極限值，一般而言柔性及剛性肋條於砂樣土壤中之拉出阻抗值並無太大差異，惟於三分石土壤中因剛性肋條受助於應力傳遞速度較快及節點強度較高之因素，故相對於柔性肋條有較好之表現。

關鍵字

拉出試驗、地工格網、剛性肋條

並列摘要

The geogrid introduced into Taiwan approximately in late 1980. Predecessors have accumulated nearly 30 years experience in the production, use, and the testing of data.
Except for the transverse rib rigidity caused by the pull out behavior has yet to see details of the testing. This paper especially for this choice of openings near the square of knitted PET grid. The nominal tensile strength of thegeogrids were 155.59 kN/m. The aperture sizes ranged from 20 to 40 mm.. The percent of opening varied from 50% to 60%. With 80% relative dry density of quartz Sand, Gravel soil. Using25, 50 and 75kPa Normal Stress Force to did the research of Pullout Behavior. Analysis material of the geogrid transverse ribs on the pull out behavior, and provide the engineering community as the use of reference.
Rigid transverse rib less vertical direction by the force of surface deformation, and thus reduce the interference effect of the bar, It can enhance the friction coefficient of static friction stage and pullout limit. Generally speaking, the flexible and rigid rib in the sand
sample soil pullout limit value is not much difference, But recipients in Gravel soil due to the rigid rib stress transfer speed and node higher intensity factors, it is relative to the better performance of the flexible rib.

參考文獻

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