Friction Prestress Losses Calculator
One-end prestress P=P0 exp(−μα−kx), α cumulative ABSOLUTE angular change, no two-end jacking/slip interactions. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
Prestress friction attenuation combines cumulative angular change with length-related wobble.
Prestress friction attenuation combines cumulative angular change with length-related wobble.1
The adopted coefficients and tendon branch determine the retained stress profile. Use this tool to calculate friction Prestress Losses from the supplied measurements and assumptions.
When to use Friction Prestress Losses Calculator
Use this tool to calculate friction Prestress Losses from the supplied measurements and assumptions. Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
How to use Friction Prestress Losses Calculator and understand its results
- Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
- Enter callerJackingPrestressPa, observedCumulativeTendonAnglesRad, observedCumulativeTendonLengthsM, callerFrictionCoefficient, callerWobblePerM, using the field meanings and rules below, then run the tool.
- Read frictionRetainedPrestressPa. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerJackingPrestressPa | Caller jacking prestress pa | number | Required |
| observedCumulativeTendonAnglesRad | Observed cumulative tendon angles rad | list of number | Required |
| observedCumulativeTendonLengthsM | Observed cumulative tendon lengths m | list of number | Required |
| callerFrictionCoefficient | Caller friction coefficient | number | Required |
| callerWobblePerM | Caller wobble per m | number | Required |
Enter nonnegative initial stress, friction coefficient and wobble coefficient, with nonempty aligned nonnegative nondecreasing cumulative angle and length lists. Return initial stress×exp(−friction×angle−wobble×length) at each sample. Units are radians and meters with compatible coefficient units; no curvature inference or two-end stressing branch is solved.
retainedStressPa_i=initialStressPa×exp(−μ×angleRad_i−kPerM×lengthM_i) Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| frictionRetainedPrestressPa | Friction Retained Prestress Pa; follow the units, sign, ordering and evidence convention stated above | list of number |
{
"input": {
"callerJackingPrestressPa": 100,
"observedCumulativeTendonAnglesRad": [
0,
1,
2
],
"observedCumulativeTendonLengthsM": [
0,
10,
20
],
"callerFrictionCoefficient": 0.1,
"callerWobblePerM": 0.01
},
"output": {
"frictionRetainedPrestressPa": [
100,
81.87307530779819,
67.03200460356393
]
}
}Limitations and assumptions
The adopted coefficients and tendon branch determine the retained stress profile. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Total Prestress Losses Calculator for this related task: Sequential fractional losses act on the remaining prestress after each stage.
Use Anchorage Slip Prestress Loss Calculator when its separate inputs and assumptions fit the question: Anchorage slip produces a modeled strain change over an independently chosen affected length.
References
-
Friction Prestress Losses Calculator — tool.io
Similar or alternative tools
- Total Prestress Losses Calculator
Sequential fractional losses act on the remaining prestress after each stage.
- Anchorage Slip Prestress Loss Calculator
Anchorage slip produces a modeled strain change over an independently chosen affected length.