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Online Slope Stability, Soil Nailing, and Inclinometer Monitoring Workshop

4 hours each day, 8 PDH

Slope stability, soil nailing, and inclinometer worksho

July 15, 16, 2020

Upcoming Workshop Series

60 hours

Data, databases, and Machine Learning for Geotechnical Engineers

Data, databases, and machine learning for civil engineers

Aug, Sep, Oct 2020

The future of civil engineering is approaching

Online Deep Excavation and Soil nail wall design Workshop

16 PDH

Apr. 22,23, 29, 30, 2020

Deep excavation in Las Vegas

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DeepEX 2020

Solving Deep Excavation Design

DeepEX 2017 talk to it and design your deep excavation!

Deep Foundation Software, Pile Rafts, Pile Groups

From soil estimation to axial and lateral pile capacity

DeepFND - Deep Foundation Software, caissons, CFA, drilled piles, driven piles, concrete, timber

From soil estimation to helical pile settlement estimation.

New helical pile software HelixPile
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What do you want to design?
DeepFND 2020: Deep Foundation software (NEW: Pile-Group/Pile Raft Analysis!)
DeepEX 2020: Deep Excavation software
Soldier pile walls
Sheet pile walls
Secant pile Walls
Tangent piles
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Soldier and Tremied Concrete
Soil Mix walls
Combined king pile sheet piles
Slope stability
Cost estimation for braced excavations
Waler-Strut Cofferdams
Snail-Plus 2019: Soil nailing - soil nailing walls
SiteMaster: Inclinometer software (adopted by Geokon)
HelixPile: Helical Pile Software
RC-Solver: Concrete Design ACI-318, EC2, EC8
Steel-Beam: Steel beam column design, full equations, AISC, EC3

Active Lateral Earth Pressures in Retaining Walls

Active pressures what is it and why?

When we excavate on one side of a retaining wall an unbalanced load condition is created. As it is very obvious, the retained side wants to move into the recently excavated zone. However, we engineers boldly introduce our retaining walls in the middle to take care of the unbalance. At a closer glance what is happening is this:

CLICK HERE TO FIND OUT THE CALCUALTIONS OF Active Lateral Earth Pressures in Retaining Walls

WITH deepEx software

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of deepEx on secant pile walls with our technical experts

a) The excavated zone gets unloaded, the zone above subgrade is removed and therefore there is zero lateral pressure on the recentrly excavated depth.

b) As a result the retained soil, which is initially at an "At-rest" state starts moving towards the excavation.

c) The result of this movement on the retained side is a reduction in lateral earth pressures from the initial state.

d) If this lateral movement keeps increasing, the driving lateral earth pressure reaches a minimum value, beyond which there is no further drop in lateral pressure. Essentially, this condition is a limit state or in other words a failure condition. This means that the soil has fully mobilized its strength.

While at a first glance this might seem unsafe, active earth pressures take place at very small displacements, typically less than 3% of the total excavation depth.

As all effective horizontal stresses, active earth pressures are defined as a ratio of the effective vertical stress times a coefficient of lateral pressure. For "active" conditions, this coefficient is typically defined as:

Ka = [1-Sin(friction angle)]/[1+sin(friction angle)]

Lateral active earth pressures can be modified to include wall friction, seismic effects, and surface inclination.

Do you have to include Active Pressures for Retaining Wall Design?

Engineers typically design gravity walls for active earth pressures and then apply a safety factor in the overall wall design. Over many years this practice has proven safe given that the retaining wall is allowed to experience small lateral displacements.

Essential software tools for engineers!