|DeepEX 2015: Deep Excavation software|
|Soldier pile walls|
|Sheet pile walls|
|Secant pile Walls|
|Soldier and Tremied Concrete|
|Soil Mix walls|
|Combined king pile sheet piles|
|Cost estimation for braced excavations|
|SnailPlus: 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|
Passive 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.
or click here to arrange a free online video presentation
of deepEx on passive earth pressures calculations with our technical experts
At a closer glance what is happening is this: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, while the soil on the excavated side gets further compressed into the excavation.
c) The result of this movement on the excavation side is an increase in the resisting lateral earth pressures from the theoretical initial state for the current excavation level.
d) If this lateral movement keeps increasing, the lateral lateral earth pressure reaches a maximum value, beyond which there is no further increase 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.
This condition, if left uncontrolled can be unsafe, partly because passive earth pressures take place at large displacements.
As all effective horizontal stresses, passive earth pressures are defined as a ratio of the effective vertical stress times a coefficient of lateral pressure. For "passive" conditions with zero wall friction and a horizontal ground surface, this coefficient is typically defined as:
Kp = [1+Sin(friction angle)]/[1-sin(friction angle)]
Lateral passive earth pressures can be modified to include wall friction, seismic effects, and surface inclination.
Do you have to include Passive Pressures for Retaining Wall Design?
Engineers typically design gravity walls for passive 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 and that the passive earth pressure is used to determine a safe wall embedment that is later multiplied by a safety factor. In Eurocode 7 the toe embedment safety factor is incorporated in soil strength reduction factors. Another approach is to divide passive pressures by a safety factor when designing a retaining wall.
DeepEX is the ultimate software for deep excavation design with umatched capabilities. Includes secant piles, soldier piles, sheet piling, diaphragm walls, and custom wall types. Includes slope stability and soil nailing. Trusted by more than 1000 engineers worldwide.
SiteMaster is our new modern inclinometer software. SiteMaster supports files from many inclinometer manufacturers such as DigiTilt, Encardio, GeoKon, ITMsoil, SINCO, SISGEO, etc. Unmatched capabilties at an affordable price. Contact us to find out!
Sign up for free software trials and to receive other valuable training materials. Join a list of more than 1000 professional engineers worldwide who choose our products and services. Receive special offers and professional service!
Let us help you with our yearly technical support contracts. We help you get realistic bids in place, including preliminary design services. Professional help and support from our expert engineers with personal training. All this for an unmatched flat annual fee.
Steel-Connect software. Easily design and evaluate many steel connections with US codes ASD, LRFD, LRFD 13th. Simple and moment strut to beam connections. Reports can be exported in Word and PDF. Automatically determine the required steel stiffeners, welds, and bolts.
Wickdrains is a simple software program that estimate consolidation times and settlements with & without vertical drains (wick-drains). With this software you can optimize your consolidation times and accelarate construction times when compressible layers are present.
Copyright © 2003 - 2015 Deep Excavation LLC. All Rights Reserved.
Web Development by QV-WEB