中文摘要：

土体含水量和干密度是岩土工程中的重要参数,现有测试方法周期长,扰动大,且无法实时进行多点自动化监测。从电磁学理论及时域反射测量（TDR）法出发,系统分析TDR传感器类型、材料及尺寸对测试精度的影响。针对现有商业化传感器的缺点,设计一种整体性强、性能可靠、价格低廉的传感器。通过专门设计的大型模型试验,对该传感器在大型工程中的应用效果进行研究与验证。结果表明,该传感器既能在现场快速测试土体质量含水量和干密度,又能长期实时监测二者在土体不同深度的变化情况,且准确度高,是岩土工程施工阶段质量控制及使用阶段安全监测的一种有效工具。

英文摘要：

Soil water content and dry density are important parameters in geotechnical engineering. Conventional measuring methods are time consuming,destructive,and automatic multipoint real-time monitoring is not achieved. On the basis of electromagnetic theory and time domain reflectometry（TDR） method,the effects of TDR sensor type,material and size on the accuracy of the measurement are systematically analyzed. A new TDR sensor with advantages of good integrity,reliable performance and low cost is designed for the disadvantages of existing commercial sensors. Then,the practicability of TDR sensor is tested and verified by specially designed large-scale model test. The results show that the new sensor can be used to measure in-situ soil gravimetric water content and dry density accurately and quickly. Furthermore,the long-term real-time monitoring of soil water content and dry density at different depths can also be implemented by it. The new sensor is an efficient tool in quality control during construction and safety monitoring in the service period of geotechnical engineering projects.