路基土壤的贯入性质及其承载力估算 - 中华大学chu 华大.doc

以DCP與IST觀察的貫入及估算其承載 楊朝平 鄭郁志 摘 要 道路之養護上需調查路基之土類、厚度承載）等因，若依規定於各區段開挖及施行現地試驗，需龐大經費且費時。為此，本研究導入簡易低價位之動態圓錐貫入儀(DCP )土壤衝擊測定器(IST )，調查路基工程性質。即以DCP觀察路基之貫入曲線性質計算其平均貫入比，路基土以IST量測路基之衝擊加速度，估算值。於實驗室以五種土為試料，DCP貫入曲線及量測與之值域，將此等結果應用於現地路基上，藉以驗証其適用性。研究發現，DCP貫入曲線鬆密狀態影響大，依轉折點可明顯區分出路基土層分界。依文獻所提之經驗式，可由量測之、估算路基之彈性模數，其估算值在合理範圍內。關鍵詞：路基、貫入、。 中華大學土木工程副教授Department of Civil Engineering and Engineering Informatics, Chuag Hua University, Hsin chu, Taiwan, 300, R.O.C. (Corresponding Author) E-mail: ycp@chu.edu.tw [2] 交通部公路總局東西向快速公路北區工程處工程司 Engineering, The North Project Office, Taiwan Area East-West Link Expressway Engineering Project, Taiwan Highway Bureau, Taipei, Taiwan, 249, R.O.C. Using DCP and IST to Observe the Penetration Curves of Subgrades and to Estimate their Bearing Capacity Chau-Ping, Yang[1] Yi-Zhi, Cheng[2] ABSTRACT It is necessary that the soil type, thickness, and California Bearing Capacity Ratio () of subgrade should be investigated in advance for road’s maintenance. However, as for roads in mountainous area, both divided trenching and field test shall not be practical due to the lack of maintenance expense. Tentatively, this study introduced simple and economical Dynamic Cone Penetrometer (DCP) and Impact Soil Tester (IST) for facilitating the investigation of subgrade and upgrading its quality. The DCP was used to obtain the penetration curves and its average penetration ratios () of subgrades for identifying their soil type and thickness. The impact accelerations, , of subgrade were measured by using IST in order to estimate their values of . The DCP’s penetration curves, and of five soils were measured in laboratory. The laboratory results were applied in the in-site subgrades for the purpose of validation. According to the results of this study, the DCP’s penetration curves vary with the unit weights of specimens. The inflection point of DCP’s penetration curve marks apparently soil layers of subgrade. Taking the empirical formula recommended by the references, both the