試驗結果顯示，當軟弱粘土層中之砂樁水平置入加勁材後，能有效提升軸向承載壓力，並將上方載重傳遞至砂樁底部。當擺設之加勁材強度大時，較密的加勁材間距可大幅提升砂樁之承壓能力。若加勁材具有較大之強度異向性，交叉擺設較同向擺設能帶來較好的效果。而不同加勁範圍方面，由試驗得知部分加勁無法達到與全段加勁相近之軸壓能力。擺設加勁材後，能束制砂樁側向腫脹程度，擺設間距較密且強度較大之加勁材，更能有效束制側向腫脹並使樁體變形更趨均勻。 This study investigates the bearing behavior of individual geosynthetic-laminated sand columns embedded in very soft clay through model tests. Similarity analysis was first executed to determine the suitable properties of the constituents used in the model test to ensure comparable behavior between the prototype-scale and model-scale geosynthetic-laminated sand columns. The model tests were conducted on three types of geosynthetics was employed to reinforce the sand columns either with 5 or 10 layers in same and cross direction of geosynthetic sheets horizontally placed in these model sand columns. Loading tests performed on soft clay, ordinary sand column (OSC) and laminated reinforced sand column (LRSC) were employed to explore the effectiveness of reinforcement and various horizontal spacing.
Experimental results showed that horizontally inserted reinforcements improve the bearing capability of the model sand columns. Using the reinforcements with high strength and smaller spacing can exhibit significant improvement in bearing capacity of sand column. Consequently, the greater amounts of stress are transmitted from the top to the bottom of the laminated reinforced sand columns, and the columns deform in a relatively uniform manner along the height of the columns. If the reinforcement has obvious anisotropic behavior on strength, then place it in cross can provide higher bearing capability. Additionally, local reinforced area in sand columns cannot obtain the close bearing capability.