Hydraulic Heave

Hydraulic Heave Equations

Hydraulic heave refers to the potential for soil to heave due to water seepage forces. As excavations get deeper, hydraulic heave can get more important, especially when more permeable layers are encountered under clays.Various building codes specify how hydraulic heave should be calculated, in general an approach according to a service analysis is to formulate hydraulic heave as:

FS Hydraulic heave = (total vertical stress - uTop)/ (water pressure - uTop)

where the total vertical stress and water pressure at are a point of interest, and Utop is the water pressure at the ground surface when the ground is submerged.

Hydraulic heave equations and basic definition

Figure 1: Basic formulation of hyrdaulic heave

Hydraulic heave according to Eurocode 7 has to be calculated according to the following:

FS Hydraulic heave = LF stabilizing (total vertical stress - uTop)/ [LF destabilizing (water pressure - uTop)]

Where LF stabilizing = Stabilizing load factor, and LF destabilizing is the destabilizing load factor according to the examine design scenario.

In general, the hydraulic heave safety factor should be greater than 1.5. For example, most Eurocode 7 national annexes define 1.35 on LF destabilizing, and 0.9 of LF stabilizing.

Groundwater flownet analysis with DeepXcav software

Figure 2: Groundwater flownet analysis with our DeepEX software program.

Groundwater head contours with DeepEX

Figure 3: Groundwater flownet analysis with our DeepEX software program showing ground water head contours.

DeepEX Software can Calculate Water Pressures for Deep Excavations

Simplified Water Flow, Hydrostatic Water Pressures, Full Flownet (Seepage Analysis)

Review DeepEX Capabilities

Solutions for Geotechnical Engineering Professionals:

Logo_DeepEX.png

DeepEX

Deep
Excavations
Design
Software

Learn More

dfnd.jpg

DeepFND

Pile Foundations
Design
Software

Learn More

HP.jpg

HelixPile

Helical
Piles
Design
Software

Learn More

SP.jpg

SnailPlus

Soil Nail
Walls
Design
Software

Learn More

FULL FEATURES DEMO  - TRY NOW

SIGN UP TO TRY ALL FEATURES, GET ACCESS FOR A FULL TRIAL

 

      Deep Excavation LLC
    240 W 35th Street, Suite 1004
    New York, NY, 10001
    U.S.A