Seismic Performance of Brace Middle‐Connection in Steel Concentrically Braced Frames with X‐Bracing
Bibliographic record
Abstract
Abstract This paper presents the experimental investigation of two brace middle connections: 1) using a slotted tube knife‐plate connection (STKPC), and 2) a bolted sandwich plate connection (BSPC). The STKPC consists of a gusset plate slotted through the continuous brace and welded to discontinuous braces. The BSPC consists of two cover plates and four U‐shaped plates connecting the discontinuous braces using bolts. The two cover plates pass on either side of the continuous brace and are bolted to the U‐shaped plates. These connections are used to join the discontinuous braces in steel concentrically braced frames (CBFs) configured with X‐bracing. These connections were tested as part of a full‐scale CBF using quasi‐static testing. In both specimens, seismic energy dissipated through yielding and buckling of the braces. However, in the specimen with STKPC, axial deformation is concentrated in a single discontinuous brace, which led to local buckling at mid‐length and subsequent fracture. In contrast, the BSPC is able to better distribute axial deformation between the two discontinuous braces delaying local buckling. Moreover, the measured buckling capacity of braces when using the BSPC matches well the expected compressive resistance calculated using an effective length factor K = 0.45.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".