EVALUASI PENURUNAN TANAH PADA PEMBANGUNAN APRON BANDAR UDARA INTERNASIONAL AHMAD YANI SEMARANG

• Main Authors: , Nindya Kusuma Dewi, , Prof. Dr. Ir. Harry Christady Hardiyatmo, M.Eng., DEA.
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2013
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/125715/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=65889
• Institution: Universitas Gadjah Mada

In Ahmad Yani International Airport, there are some development plans, one of which is developing the existing apron. Unfortunately, the soil condition is soft soil. If there is no soil improvement, there will be settlement problem. Settlement caused by soil consolidation may take some times to be considered complete, and it can cause some construction damage. Therefore, there is soil improvement using preloading method and vertical drain before construction. It needs evaluation of soil settlement in the field to evaluate whether it has the same value as the planned or not. This study predicts the value and the time of consolidation using Terzaghi�s method, vertical drain, graphically estimation with the least square method , and the Asaoka�s method. The data from piezometer�s measurement is used to determine the degree of consolidation at the last time observation, so the consolidation settlement can be predicted. The settlement results of all methods are compared with the results of actual settlement in the field. Besides that, this study also predicts the comparison of horizontal coefficient of consolidation that is used in theory (planning) and the actual value in the field.The degree of consolidation results that obtained at the end of the last time observation in the field has the highest value at 100% for area 4 and has the lowest value at 72% for area 3. The difference of the settlement value at the last time observation between the actual and using vertical drain is from 29% to 54%, with a graphical method assuming t0 obtained at the end of the preloading is from 6,3% to 21,3% , with a graphical method assuming t0 obtained in the middle of the preloading is from 2,1% to 18,3% , and Asaoka�s method is from 7,4% to 21,3%. The horizontal coefficient of consolidation in the field (from the graphical method) is greater than that used in the theory (planning calculation with vertical drain). There is an error in area 1. The ratio of Ch that used in the theory and in the field which calculate by the graphical method assuming t0 obtained at the end of the preloading is from 1:2 to 1:10, and the biggest difference is 89,5%. The ratio of Ch that used in the theory and in the field which calculate by the graphical method assuming t0 obtained in the middle of the preloading is from 1:2 to 1:6, and the biggest difference is 83,9%.