Corrugated High-Density Polyethylene Pipe: Laboratory Testing and Two-Dimensional Analysis to Develop Limit States Design
Bibliographic record
Abstract
Baseline data on buried thermoplastic pipe behavior under biaxial loading have been developed in a controlled laboratory environment. Deflections and local wall strains of a lined corrugated high-density polyethylene pipe were determined. Use of the finite element method and simplified design equations was then evaluated relative to the laboratory measurements. Measurements of soil response during the tests were used to evaluate the constitutive response for the soil. The comparisons reveal that the two-dimensional finite element method can effectively be used to predict pipe deflections and circumferential strains in the corrugation, given that appropriate material parameters are used. Liner strains, however, are influenced by local bending, so that three-dimensional analysis is required. The simplified design methods were shown to be effective tools for pipe design. A strain factor of three in the semiempirical equation for circumferential bending strain appears to be reasonable for pipes buried in uniform ground. The finite element method was then used to study lined corrugated pipe response when the zones of backfill placed beneath the haunches have low density and modulus. These alter the location of the peak strains, may significantly increase the magnitude of the circumferential strains and the strain factor, and induce yield at the extreme fibers.
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 | 0.002 |
| 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 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".