Verification and simulation of database for design parameters of clays

大地工程在施作前會透過各式各樣的現地調查與試驗，從基本簡單低成本的試驗、鑽探，到費時高成本如壓密試驗等，量測設計所需的工程參數，做為日後設計建物時重要的依據。 進行可靠度分析時，基本上希望土體的不確定性越小越好，但即使經過現地調查探勘，現地整塊的土體仍然有不確定性的存在，而深度較深或不易量測的土體則無法避免有較大的不確定性，進而影響設計參數。 為此，本研究針對現地試驗中低成本易取得的黏土土壤試驗參數諸如:含水量、塑性、單位重、應力歷時、剪力強度、CPTU試驗…等，根據本實驗室近年累積的大量參數資料加以整理，進一步形成一個更加完整的資料庫，並將上述參數種類中選取具備代表性的十種參數作為分析資料庫，其餘參數則作為驗證資料庫使用。 由於本研究採用的參數較多，資料庫的資料其真實性與可靠性更顯的重要，進一步會影響相關系數矩陣的建立；而相關系數矩陣的建立也與後續參數模擬息息相關，因此，資料庫的可靠性驗證與分析資料庫參數之相關系數矩陣的建立為本研究之核心。Geotechnical parameters are the basis of designing a geotechnical facilites. These parameters were given through a variety of field investigation and trial, from a simple low-cost test, drilling to a time-consuming and espensive test such as the compaction test. Basically, the uncertainty of the soil for reliability-analysis should be as small as possible, but the uncertainty still remains even after the site investigation is completed. The soil in deeper depth which is difficult to measure can not be avoided with greater uncertainty. These uncertainties will affect the design parameters. In this study, we focus on some fundamental clay’s parameters such as: water content, plasticity, unit weight, stress lasted, shear strength, the piezocone test ... and so on. Our laboratory’s research has accumulated a large amount of clay’s parameter data in recent years, and this research will organize the data to a more complete database. We selected ten of the above parameters to be the calibration database, and the remaining parameters as validation database. Because of using much more parameters in this study than previous research, the authenticity of the database is more important, which will further affect the establishment of the correlation matrix; the correlation matrix is also closely related to the follow-up parameter simulation, therefore, the database reliability verification and establishing the correlation coefficient matrix of the calibration database are the two main core of this study