SBIR Phase II: Development of a Flexible Flatjack for Quantitative Evaluation of Masonry

*** 9318740舒勒这个小企业创新研究二期项目旨在开发一种可靠且廉价的方法来获得砌体建筑的压应力状态和变形特性的原位测量。这些测量是评估现有砌体建筑结构完整性的基本要素。目前，这些测量是使用扁平千斤顶进行的（气囊使用边缘焊接在一起的薄金属片，并带有进、出口）。目前的平板千斤顶技术存在一些严重的局限性，降低了测量的准确性，限制了可以评估的砌体类型，并可能导致结构的视觉损坏。第一阶段研究调查了可用于制造柔性平板千斤顶的候选材料，设计和制造了柔性平板千斤顶的原型，并测试了原型对砖石墙的适用性。在第二阶段，原型设计将进一步发展，以提高性能，延长使用寿命，降低制造成本。将完成变形传感器的整合，并进行全尺寸评估。作为第二阶段工作的一部分，还将提出修改国内外现有检测标准的建议。对新的平板千斤顶技术的需求是由修复现有砌体结构的需求驱动的，以满足新的、更严格的地震载荷，并用于改造这些结构以改变用途。美国和世界其他地区现有的大量砖石建筑，以及作为改造基础的评估需求，预示着一种成功的新平板千斤顶技术的高水平使用。＊＊＊

*** 9318740 Schuller This Small Business Innovation Research Phase II project is designed to develop a reliable and inexpensive method for obtaining insitu measurements of the state of compressive stresses and deformation properties of masonry buildings. Such measurements are essential elements in the evaluation of the structural integrity of existing masonry buildings. Currently these measurements are made using flatjacks (bladders using thin metal sheets welded together at the edges and with inlet and outlet ports). Present flatjack technology has some serious limitations which reduce the accuracy of measurements, limit the types of masonry that can be evaluated and may result in visual damage to the structure. Phase I research surveyed candidate materials that could be used to fabricate a flexible flatjack, designed and fabricated prototypes of flexible flatjacks, and tested the prototypes for applicability to masonry walls. In Phase II, prototype designs will be further developed to improve performance, increase service life and decrease manufacturing costs. Incorporation of deformation sensors will be accomplished and full scale evaluations will also be conducted. Recommendations for modifying existing testing standards, both domestic and foreign, will also be developed as part of the Phase II effort. The need for a new flatjack technology is driven by requirements to rehabilitate existing masonry structures to meet new, more stringent seismic loadings and for use in renovating such structures for changing uses. The large number of existing masonry buildings in the U. S. and the rest of the world and the demonstrated need for evaluation as a basis for retrofit portend a high level of use for a successful new flatjack technology. ***