公路护栏立柱埋深无损检测技术及影响因素研究

【作者】 张潇；

【导师】 贾志绚；

【作者基本信息】 太原科技大学 ， 车辆工程， 2011， 硕士

【摘要】 高速公路护栏立柱的埋置深度直接关系到驾驶员的生命财产安全,由于缺乏有效的检测措施,导致在施工时发生埋置深度不足的质量问题。目前,施工中普遍采用拔桩法进行检测,但该方法需用专用拔桩机械,且检测完毕后立柱需要重新打入,给工程监理和检测人员带来诸多不便。因此,需要一种即快速无损又准确可靠、便于携带的设备来解决立柱埋深的检测问题。本文在研究了一维杆件弹性波的传播特性基础上,分析了护栏立柱装置处于不同状态下,即立柱是否连接护栏板、立柱与护栏板的相对连接位置、是否安装柱帽,传感器的选择及安装位置、力锤的选择及激振位置等对半埋地立柱埋深的弹性波检测法的影响,初步研究了不同状态下检测频率的变化及对测量结果的影响,通过试验、回归分析得出立柱连接护栏板后影响因子的取值范围。初步试验结果表明,当立柱与护栏板处于非搭接位置时,检测频率多集中在950¹000Hz,处于搭接位置时,检测频率多集中在875⁹25Hz,相应的校正因子ψ1的取值范围为1.25¹.22及校正因子ψ₂的取值范围为1.32¹.25,且校正因子的取值大小随检测频率的增加而降低。该方法为工程实地检测立柱的埋深提供了一种可行方案,也为开发便携式立柱埋深检测设备提供了理论依据及试验基础,但校正因子的精确取值还需进一步试验论证。更多还原

【Abstract】 Expressway guardrail post embedded depth which directly related to the driver’s life and property security, but due to the lack of effective detection measures, resulting in serious quality problems when construction . At present, the inspection of post embedded depth widely by pulling piles manual inspection. But this method needed special tension piles machinery and to be buried the foundation once again after each inspection which brought a lot of trouble to inspectors. Therefore, we needed a kind of rapid and reliable detection method and a type of portable equipment to settle the matter that the depth of guardrail post embedded.In this paper, the elastic wave propagation was researched on the basis of one-dimensional rods and the different conditions of guardrail post device were analyzed, Such as whether or not to connect with guardrail plate and install rubber cap, the relative position between guardrail and post, sensor types and its installation locations, vibration hammers and the stations for exciting vibration etc. which influenced the test results that the length of half- buried post by the detection method of elastic wave. The change of detection frequencies and the influence of the detection results were analyzed preliminarily on different states. The range of correction factors were obtained in various states by experiments when post connected with guardrail plate.The preliminary test results demonstrated that when the post at the non-lap position the detection frequency mostly were from 950 to 1000 Hz and the correction factorsψ1were from 1.25 to 1.22, when the post at the lap position the detection frequency mostly were from 875 to 925 Hz and the correction factorsψ2were from 1.32 to 1.25. It not only provided references for detection persons in engineering field which inspected the depth of post embedded in soil but also provided the theoretical and experimental proof for engineering test and developing portable inspection equipment. But it remained to be further verified the accurate value of correction factor through the experiment.更多还原