Design of a TL-4 Median Cable Barrier for Deerfoot Trail, Calgary
Bibliographic record
Abstract
This paper describes the preliminary engineering and design, by EBA Engineering Consultants Ltd. (EBA), of a National Cooperative Highway Program (NCHRP) 350: Test Level 4 (TL-4) high-tension (pre-stretched post-tensioned) cable barrier installed in May 2007 in the depressed median of an 11 km stretch of the Deerfoot Trail in Alberta, Canada. The paper reports the results of the research regarding the available TL-4 cable barriers approved by the US Federal Highway Administration (FHWA). The paper discusses important design considerations, such as the post spacing and allowable maximum deflection of the cable barrier, and the recent revisions to the AASHTO Roadside Design Guide. For the Deerfoot Trail project, a design deflection of 2.4 m (8 ft) and a maximum post spacing of 6.1 m (20.0 ft) was specified. The median cable barrier was placed 4.0 m from the edge of the travel lane (the painted shoulder line). This minimized the interaction with existing barrier systems, and allowed for emergency vehicles to park or pass on the inside shoulder. The authors believe that the research and design of the high tension cable barrier described in this paper should be of interest to future similar projects in Canada.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
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".