New Design Methodology for Seismic Column-to-Foundation Anchorage Connections

Connecting columns to existing foundations is often required in rehabilitation projects and where connecting reinforcement was not installed properly. Because it is not possible to post-install bent bars into cured concrete and guidance for post-installed connection bars in such situations is scarce, the article is highly welcomed as addressing a strong need from practice. The tests clearly show that, even for cyclic earthquake loading, slab to column connections can be achieved with straight connecting bars as long as they are embedded sufficiently deep in the foundation. A few observations should be made on the proposed design concept. connections are significantly inferior to the development length specified by ACI 318, Chapter 12. However, the design concept may require significantly deeper anchorage depths than Chapter 12 in the case of walls connected to floors. In summary, the proposed design concept is usually a conservative approach to designing moment-resisting connections with straight bars.