An Alternative Rocking CLT Shear Wall System
Bibliographic record
Abstract
Seismic-force-resisting systems (SFRS) using cross-laminated timber (CLT) shear walls lack the benefit of standardized guidance that includes external energy dissipation systems. The low seismic force reduction factor (R) values for mass timber shear walls in ASCE 7-22 are based on the nonlinear mechanisms in the wall panel connections. In a recent project in San Francisco, CA, Tipping Structural Engineers explored utilizing mild-steel butterfly fuse connectors with rocking CLT panels to reduce the seismic demand. The SFRS of the building consist of CLT wall panels connected with steel butterfly fuses to dissipate input earthquake energy. The CLT shear walls are connected to the foundations using steel pins at either end. This enables the connected CLT panels to achieve rocking motion under lateral loading. The butterfly fuses experience nonlinear shear deformation due to the relative movement of the CLT panels and dissipate energy. Rocking actions only occur on the central panels because the designed gaps below each of the two side panels allow them to pivot freely around the pins. The seismic response of the proposed system is characterized primarily by the rocking mechanism and the shear yielding of butterfly fuses. Since this lateral load resisting system is not prequalified in ASCE 7-22, a peer-reviewed performance-based approach was used to validate the design utilizing nonlinear pushover analysis. The validation studies demonstrated the effectiveness of the system design using a R factor of 8. The study was extended to include non-linear shaking simulations to explore the basic mechanics of this innovative system. Procedures based on the analytical model are provided to select the butterfly fuses in preliminary design.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.012 | 0.004 |
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".