1General and settings
Input project details and the analysis unit system.
Appearance
Project details
Units
Constants
2Geometry
Input analysis geometry, including the outline, foundation interface, any cutouts (galleries etc.) and downstream rock wedges.
Section shown to the right will update as changes are made.
Section outline
Accepts DXF, 3DM with single curves or CSV/TXT with X-Y coordinates
Internal geometry
Cut-outs or voids within section (i.e. gallery)
Lift joints
Assign lift joints → properties may be set separately
Interface plane
Define the foundation interface plane, must be a straight line plane between two points
Downstream rock
Input downstream rock level and its profile.
7Bearing and crushing
Set the toe stress limits for concrete crushing and foundation bearing.
Off: concrete crushing is not checked.
Checked at the toe of every plane (foundation interface and lift joints).
Off: foundation bearing pressure is not checked.
Checked at the toe of the foundation interface only.
6Downstream wedge
Set the contribution of a downstream rock wedge (if applicable).
Wedge behaviour: rock mass control
Different failure angles will be tested, and the lowest breakout resistance is selected automatically.
Wedge behaviour: defect control
Failure will be forced through the user-assigned defect.
The offset run is sheared flat through the rock mass, from the toe to the start of the defect.
3Drains and anchors
Input drain and anchor positions along with drain behaviour during flood. Drains crossing an analysis plane will automatically apply the uplift reduction specified by the user in steps 7 and 8.
Drains
Enable formed drains in the concrete, running parallel to the upstream face.
Anchors
Post-tensioned anchors. Each one acts on every plane below its head.
Anchor force calculator
Converts the load in one anchor and the spacing between anchors along the dam into a force per unit length of dam, in the units the model uses.
4Load partitions
Reservoir levels and earthquake loads, each with its annual exceedance probability (AEP). Type AEP as 1 in 100, 1:100, 0.01, 1% or 100.
5Tailwater, silt and scour
Set the tailwater for each headwater, the silt against the upstream face, and how toe scour undermines the dam when it overtops.
Off: no tailwater is applied anywhere in the analysis.
Off: no silt load is applied anywhere in the analysis.
Submerged silt against the upstream face, with fixed values. Horizontal pressure is K₀·γ′·depth below the silt surface, with K₀ = 1 − sin φ′ (at rest). Vertical load is γ′·depth on any part of the face that slopes towards the reservoir. Water still acts on the full face and uplift is unchanged. Each plane only takes the silt above its own level.
Off: toe scour is not modelled.
How far scour undermines the dam, cutting back under the toe, for a given depth of overtopping (headwater above the crest). Interpolated between points, zero with no overtopping, and the last value is held beyond the last point.
9Strength distributions
Give each input a fixed value or a distribution. Each plot shows the full distribution (light shading), the mean (black line) and the 5–95% range, where the middle 90% of samples fall (dark shading).
8Quick solve
Deterministic solve with fixed values. Choose a plane, then move the sliders. Use it to find problem planes before setting up the Monte Carlo run.
Saved states
Water levels
Interface strength
Drains
General
Downstream wedge
Silt
Toe scour
Combined probability
The probability of each input being this bad or worse (at or below the slider value), from its Step 9 distribution, multiplied together for this combination. Assumes the inputs are independent. Inputs that are fixed, or that don’t act on this plane, are left out.
Apply deterministic solver to all planes
Uses the strength inputs set in the box above. Select the water levels and tailwater, then run to find the critical planes.
10Assign strengths
Choose which strength set from Step 9 each plane uses in the Monte Carlo run. The downstream wedge uses its fixed strengths from Step 6.
Planes
Values shown are the means of each Step 9 distribution. Strength sets are made in Step 9; add a custom set there for an unbonded joint or a weak layer.
11Run settings
Choose the water levels, planes and number of samples, then run the Monte Carlo solve. Each plane uses its strength set from Step 10.
Water levels
Select which planes to run
Samples
Run
The tool first solves a small batch on your computer to estimate the run time, then asks before starting.
12Results
Probability of failure for each plane and water level, from the last Monte Carlo run: sliding, plus toe crushing or bearing where set in Step 7.
Probabilities depend on the input distributions you chose and the simplified sliding model. Treat them as one input to your judgement, not as the answer.
10Load ranges
Choose which reservoir levels the Monte Carlo run solves, and how tailwater is set for each one.
Reservoir levels
Tailwater
RRebrand switches Temp
Each part of the DSC Tools rebrand can be turned off here, to compare or roll back. Kept in this browser only. Calculations and results are not affected by any of them.
Switches
This step is planned for a later build.