新型三轴剪切试验试样排水固结装置的研制与应用

Development and Application of Drainage Consolidation Device Used for New Type Triaxial Shear Test Samples

三轴剪切试验是岩土工程中常见的室内试验,其目的主要是为了获得土的抗剪强度指标和土中孔隙水压力的变化情况。三轴的固结不排水剪(CU)和固结排水(CD)剪试验可以获得土的总应力抗剪强度指标和有效应力抗剪强度指标,因此具有其它剪切试验无法替代的优势。但因试验过程中排水固结的时间很长,影响了试验进度,从而影响到整个工程的进度和经济效益。通过对三轴剪切试样排水固结过程的机理分析,介绍了制作一种可以大大缩短大量试样排水固结时间的装置及该装置的研制方法。采用该装置,可使CU试验的效率提高6～12倍,可使CD试验的效率提高3～6倍。可节约大量的生产成本,提高工作效率,经济效益明显。

Triaxial shear test is one of the familiar laboratory tests in geotechnical engineering industry. The goal is primarily to obtain the shear strength index and changes of pore water pressure of soil. Shear strength indexes of total stress and effective stress could be obtained by consolidated undrained triaxial test （CU） and consolidated drained triaxial test （CD）, so both of the tests have some special advantages not being replaced by other shear tests. However, the time spending on drainage consolidation during tests is too long to guarantee the progress, and consequently influences the schedule and economic benefits of the whole project. This paper presents a device which could be used to considerably reduce the drainage consolidation time of subs tan tial samples and describes its development method by analyzing mechanism of drainage consolidation process of triaxial shear specimen. Adopting this device, the efficiency of CU test and CD test could be increased 6 ~12 times and 3~6 times of the traditional one respectively. It could be used to significantly lower production cos ts; improve efficiency and obviously increase economic benefits.