SBIR Phase I: Pneumatic Scour Measurement System

这个小企业创新研究（SBIR）一期项目解决了在洪水条件下测量桥梁基础周围冲刷深度的问题。在桥墩周围聚集的洪水碎片形成了鸟巢，通过产生过多的湍流和阻止传统的冲刷检测技术，加剧了冲刷。气动冲刷检测系统（PSDS）解决了两个问题，测量冲刷通过一个鸟巢的碎片和承受洪水传播的碎片的破坏。这种技术是基于气流通过由烧结黄铜制成的多孔过滤器的垂直阵列的不同阻力。过滤器阵列被密封在用作探针的探头的壁上，并像大钉子一样穿过鸟巢进入靠近码头的河底。浅层过滤器暴露在水中，深层过滤器暴露在肥沃的土壤中。2002年全国桥梁清单列出了22,414座严重受影响的桥梁，其中许多都有鸟巢的碎片。洪水带来的碎片掩盖了码头周围的河底，使现有的所有冲刷检测仪器（如声纳测深仪、探地雷达）失效，并妨碍了目视检查，限制了桥梁工程师在洪水事件中确定桥梁安全的能力。PSDS探头永久安装在冲刷关键桥墩附近，探头顶部捆绑了多个气动软管，当洪水发生或预计发生时，可以轻松连接到场外便携式压力测量仪。一旦安装，桥梁工程师就可以获得码头冲刷情况的实时信息，使他们能够在危险情况发生时关闭桥梁。此外，每年对冲刷情况的监测为桥梁工程师提供了冲刷深度的知识，然后能够在码头移动之前安排补救措施，将维护成本降至最低。

This Small Business Innovative Research (SBIR) Phase I project addresses the problem of measuring scour depth around bridge foundations under flood conditions. Flood-borne debris collecting around bridge piers forms bird's nests that aggravate scour by creating excess turbulence and preventing conventional scour detection techniques. The Pneumatic Scour Detection System (PSDS)addresses both problems of measuring scour through a bird's nest of debris and withstanding the ravages of flood-borne debris. This technique is based on the differential resistance to airflow through a vertical array of porous filters made of sintered brass. The array of filters are sealed into the wall of a probe used as a probe and battered through the bird's nest into the river bottom adjacent to the pier like a large nail. Shallow filters are exposed to water, and deeper filters are exposed to competent soil.The 2002 National Bridge Inventory lists 22, 414 scour-critical bridges, many with bird's nests of debris. Flood-borne debris masks the river bottom surrounding the pier, making ineffective all currently available scour detection instrumentation, such as sonar depth sounders, ground-penetrating radar, and precludes visual inspection, limiting the bridge engineers ability to determine the safety of the bridge during flood events. The PSDS probe is permanently installed adjacent to scour-critical piers with the multiple pneumatic hoses bundled at the top of the probe for easy connection to an off-site portable pressure measurement instrument when flood events are in progress or anticipated. Once installed, the bridge engineers have available real-time information of the scour conditions at the pier, enabling them to close the bridge to traffic when dangerous conditions develop. Additionally, yearly monitoring of the scourconditions provides the bridge engineer the knowledge of depth of scour and is then able to schedule remediation before pier movement occurs, keeping maintenance costs to a minimum.