Pacific Earthquake Engineering Research Center

Invitation

We invite you to participate in the prediction of the strength of a reinforced concrete deep beam intended to represent a slice through a thick foundation mat. Competition image above shows a photograph of the test specimen after removal of formwork but before testing (Notice lab personnel for scale).

The test specimen will be simply supported along a 70-ft (21.3-m) span and loaded by self-weight and concentrated downward force located at midspan. The test objective is to obtain data on shear strength of thick foundation mats having high-strength longitudinal reinforcement and either no transverse reinforcement (Span 1 to the right of the concentrated load) or ACI “minimum” transverse reinforcement (Span 2 to the left of the concentrated load). The target test dates are late September and early October.

We designed this blind prediction contest for relatively easy participation. We only ask that you predict the failure mode and strength of each of the two spans of the deep beam. You may use a strength calculation method involving any degree of sophistication that you choose, although the relatively short time available for this contest will favor design-oriented methods.

In addition to providing your own prediction, please share this invitation with your colleagues and encourage them to participate. The invitation is open to anyone in the structural engineering field. We hope to get as wide a response as possible worldwide among practitioners, researchers, and students.

We will announce the laboratory test results, compare failure modes and measured strengths with the range of predicted results, and identify those participants who predicted failure modes and strengths closest to the test results. Results should be available before the end of October 2021.

Credits

The test specimen was constructed by staff of the Department of Civil and Environmental Engineering at UC Berkeley and a construction team from Level10 Construction. The laboratory test will be carried out in the Structures Laboratory at UC Berkeley. Primary sponsors include: Pankow Foundation; ACI Foundation - Concrete Research Council; Concrete Reinforcing Steel Institute; Level 10 Construction; MKA Foundation; Cascade Steel Rolling Mills; and nVent Lenton.