Title: TOWARDS THE DEVELOPMENT OF DIRECT CRACK-BASED ASSESSMENT OF STRUCTURES
Author(s): Paolo M. Calvi, Giorgio T. Proestos, David M. Ruggiero
Publication: Symposium Paper
Appears on pages(s): 9.1-9.20
Keywords: assessment, beams, bridges, cracks, finite element, membranes, reinforced concrete, shear
Much of the post-war reinforced and prestressed concrete infrastructure in North America and Europe is reaching its design life and engineers are in need of tools that can be used to assess the shear behavior of these structures. The Compression Field Theory (Collins, 1978) and the Modified Compression Field Theory (Vecchio and Collins, 1986) form the basis of a suite of design procedures and software that engineers can use to assess concrete structures subjected to shear. The complexity of these tools varies from simple hand calculations, such as the sectional design procedures or strut-and-tie procedures in CSA A23.3-14 and AASHTO-LRFD, to sectional software tools, such as Response-2000, and full finite element programs such as VecTor2. This paper describes how such tools can be used to evaluate shear-critical structures in the context of assessing inventories of bridge structures. A preliminary crack assessment procedure, capable of providing estimates of the residual capacity of bridge girders based on crack slips and crack widths, is also presented. This procedure is based on the Pure Mechanics Crack Model and builds on existing compression field approaches. The tool is envisioned as a means of moving from traditional bridge inspection procedures to more complex methods, based on the theoretical advancements that have been made over recent decades.