隨著城市化進程的持續推進，大都市地區現有基礎設施的擴展變得勢在必行。然而，可用於建設這些基礎設施的土地極為有限且造價昂貴。窄式地工合成材料加勁擋土牆（Narrow GRS wall）提供了一種潛在解決方案。但目前對於窄式GRS擋土牆的行為，尤其是其在地震期間的動態表現，仍缺乏詳細資訊。因此，對於台灣和印尼等地震多發地區來說，確保此類擋土牆的安全性至關重要。 為了填補這一研究空白，國立中央大學的地工離心機正在進行一系列離心模型試驗。測試的四種結構類型包括：無連接的單面窄式GRS擋土牆（SF_U），有連接的單面窄式GRS擋土牆（SF_C)，無連接的雙面窄式GRS擋土牆（DF_U），有連接的雙面窄式GRS擋土牆（DF_C）。每面擋土牆都經歷多次不同強度的地震動輸入，以評估其短期與長期性能。此外還建造了兩面相同結構的擋土牆，以面對面方式排列（同相與異相方向），進一步分析牆體排列對擋土牆動態行為的影響。這些擋土牆的長高比（L/H）為0.5，採用十層地工合成材料加勁，垂直間距為0.60 m，在原型規模下總高度達6.0 m。回填土為乾燥均勻級配砂。所有試驗均在40 g 人工離心加速度場下進行，以評估各種擋土牆的短期與長期表現。 試驗結果顯示，雙面窄式GRS擋土牆在地震動作用下比單面窄式GRS擋土牆表現出更好的抗震能力，具體表現在其位移較小，且能承受更高強度的地震動輸入。此外，採用力學連接顯著提升了擋土牆的動態表現，使牆頂位移減少49.67% 至500.72%，並增加了可承受的主震次數。 ;The ongoing process of urbanization has necessitated the expansion of existing infrastructure in metropolitan areas. Moreover, the available land for building this infrastructure is quite limited and costly. The Narrow Geosynthetic Reinforced Soil (GRS) Wall can offer a solution. However, there is little detailed information regarding the behaviour of narrow GRS walls, particularly concerning their dynamic performance during earthquakes, making it vital for areas prone to such events, like Taiwan and Indonesia, to ensure safety. A series of centrifuge modeling tests are being conducted using the geotechnical centrifuge at National Central University to address an existing gap. The four types of structures being tested are unconnected single-facing narrow GRS walls (SF_U), connected single-facing narrow GRS wall (SF_C), unconnected double-facing narrow GRS wall (DF_U), and connected double-facing narrow GRS wall (DF_C). Each wall is subjected to multiple shaking events with varying input motion intensities to assess their performance. Additionally, two identical walls are constructed face-to-face (in-phase and out-phase direction) to analyze further how wall arrangement influences behaviour. The walls are built with an aspect ratio (L/H) of 0.5, featuring ten layers of geosynthetic reinforcement and a vertical spacing of 0.60 m, reaching a total height of 6.0 m in prototype scale. Dry uniformly graded sand serves as backfill. All tests will be conducted under a 40g gravitational acceleration to evaluate the performance of each wall. The test results indicate that the double-facing narrow GRS walls exhibit greater dynamic resilience than the single-facing narrow GRS walls, as evidenced by lower displacements under input motion and higher input motion instances. Furthermore, introducing an interface connection (frictional and mechanical) considerably enhances dynamic performance, reducing top wall displacement by 49.67% to 500.72% and increasing the number of input main shaking events.
