Should geotechnical engineers charge by the hour or by the value of what they bring? I recently had what can be perceived as a heated...

FEM or LEM? A false choice in geotechnical engineering. Computers and computerized analyses are genuinely great tools that can sometimes lead us astray from delivering a true engineering solution. Many engineers are carried away by beautiful colors from finite element analyses to represent a true analysis. Others question whether a finite element analysis or a limit-equilibrium analysis is the right way to go in geotechnical problems. The surprising answer is both and none. E

In a recent linked in poll, we asked the question who should design deep excavations and why. The motivation was the fact that in some states within the US, laws or statutes have passed that recognize only structural P.E. as the ones responsible for the design of deep excavations. The poll results above appear to indicate that the engineering community believes that an engineer should be familiar with both principles and that this requirement can only do harm. In fact, profes

The aftermath of Sandy found many underground structures such as tunnels and parking garages inundated with water. In reality there might...

The geotechnical activity index is a new index that reports on the geotechnical potential in each State within the US. The index takes into consideration the geotechnical activity and population in each state. The main objective is to track changes over time in geotechnical and foundation works. As with any index, the results do not necessarily exact but should be taken as approximations of reality. Summary The GAI index showed a marked increase in December of 2013, but a mar

In many deep excavations, geotechnical engineers only specify the lateral earth pressures that are to be used by the shoring designer. An example such specification could go like: Lateral earth pressures are to be calculated with a rectangular earth pressure diagram of 24 H (in psf) above the water table and 12 H (in psf) below the water table. The equivalent fluid pressure for lateral earth pressures should be taken as is 21 pcf on the active side and 185 pcf on the passive

Increased congestion in urban cities has caused an increased demand for underground space (typically underground parking, infrastructure, or facilities). For typical high rise buildings the developer selects an architect who is responsible for presenting an overall concept for both the superstructure and substructure. While the superstructure is the prime turf for architects, geotechnical/foundation engineers are the experts for the substructure. Too often original architect

Unconservative designs with AASHTO LRFD methods for multi-level braced excavations. You would tend to think that AASHTO LRFD is always extremely conservative for deep excavations. After you read this article you will find out that this is not always the case. The main issue with LRFD is that it's recommendations have their origins directly in a structural engineering approach of a non-linear elastoplastic problem. AASHTO LRFD refers to FHWA apparent earth pressure diagrams th

No geotechnical data - the lack of proper geotechnical data in shoring designs. This appears to be the issue that most deep excavation/shoring designers and contractors are concerned about. Too often, a shoring designer is engaged on the last stages of a project, typically retained only by the specialty contractor. In most cases, when geotechnical data is available, it only includes SPT blow counts and limited geological background. Too often boreholes do not extend below (or

Contribute to our Industry: Grand Challenges in Earth Retaining Structures One of the action items that came from the ASCE/G-I Earth Retaining Structures Committee conference call on 09 July 2013 was the need to identify the “Grand Challenge” issues within the field of earth retention systems. Grand Challenge issues are those issues that are transformational in nature. These are issues that if addressed, will have a significant impact on the current approaches to the design a

Is it a structure or is it earth? We recently conducted a poll in LinkedIn on the perception of structural engineers on earth retaining structures. In this poll almost 50% of the responding “structural” engineers felt comfortable designing any type of an earth retaining structure. Only 5% passed such work to a geotechnical engineer, while 9% voted as being involved in shallow basement walls. 34% voted that they sometimes are involved in designing earth retaining structures: W

Support of Excavation Software – Where We Are and Where We Are Heading I am really excited about presenting at the DFI-CSCE 18th Annual Geotechnical Seminar: State of the Art in Performance Monitoring and Computer Applications in Geotechnical Engineering. Four Points by Sheraton, Meriden, CT This annual geotechnical seminar is presented jointly by DFI and Connecticut Society of Civil Engineers geotechnical committee. We use computers and technology every day in engineering pr

Deep Excavation CEO, Dimitrios Konstantakos, P.E is named as the recipient of the 2018 ASCE Martin S. Kapp Foundation Engineering Award! We want to recognize all Deep Excavation employees as equal recipients of this award. Dimitrios Konstantakos, P.E. We are very excited that this award was due in part to our recent work with HoloDeepEX! Solutions for Geotechnical Engineering Professionals: DeepEX: Deep Excavations Design Software DeepFND: Pile Foundations Design Software Hel

Determine soil parameters when you don't have all the data. Geotechnical uncertainty is a major issue in deep excavation and geotechnical design. Minimizing uncertainty and estimating design soil property presents a major challenge to engineers. Most projects have only SPT test data, and different methods can result in widely varying strength estimates. Reviewers often ask for justification of estimated soil strength parameters, so how does one meet these challenges? In DeepE

2015 International Foundations Congress & Equipment Exposition (IFCEE 2015). We are very excited to support the following two sessions for the 2015 conference! We encourage you to contribute by submitting an abstract. Track E- Earth Retention and Stabilization Session 5 – Working in Dense Urban Environments Earth Retention and Underpinning in Dense Urban Environments Co-Sponsoring Committees: ASCE Earth Retaining Structures Committee Session Leaders: Robert Alperstein, PE, M

2014 has seen considerable improvement in geotechnical construction activities within the United States. Big metropolitan cities, such as New York, Los Angeles, San Francisco, Miami, and Seattle have seen an expansion of luxury residential construction. 2014 also saw the one of the best years for commercial projects since 2009. We expect this trend to continue in 2015, and will put a strain on companies looking for engineering professionals to staff job sites. Infrastructure

Lateral surcharges from railway on temporary retaining walls Discussing earth retaining wall design issues with transportation or railway authorities sometimes feels like talking to a wall. Transportation officials basically have their hands tied by code or design manual, even when the code is taken out of context. An example of such case is the AREMA manual specifications for lateral surcharges on retaining walls. Most times the specifications are taken out of theoretical co

After a series of serious newsletter items we thought of give everyone a small reason to smile. This limited list provides some of the funny geotechnical terms that we have encountered. Have fun :) Abudment: An abutment meets Budweiser (beer) Bed rock: Rock music that you listen when you go to bed Cut-and-cover: Mafia style, cut soil, cover evidence. Excavation: What support, just bring a back hoe? Dirt: What your non geotech spouse calls soil Experience: Repeating the s

The best job in the world is a deep excavation engineer! The best job in the world is a deep excavation engineer. My 2.5 year old son loves Peppa Pig with the biggest muddy puddle in the world. His face fills with happiness when he spells out "Muddy Puddle". A few days ago, I described to him that daddy designs "very big Muddy Puddles". Thus for most kids we have the best job in the world. As deep excavation engineers though, we make the biggest muddy puddles in the world saf

FUNNIEST GEOTECHNICAL & EXCAVATION IMAGES! With 2016 almost over, these are some of the funniest 2016 pictures related to geotechnical, construction, and excavation issues that we found! 1. CATERPILLAR SUBMARINE - PERISCOPE UP! 2. BUILDING FOUNDATIONS ACCORDING TO AASHTO STANDARDS 3. THE NEW LINE OF EXCAVATORS OPERATES UNDER ALL MOISTURE CONDITIONS 4. WRAP AROUND COLUMN STABILIZATION METHOD 5. DO NOT OWN A PLANE IF YOU FIRE YOUR EXCAVATION OPERATOR 6. HOW GEOTECHNICAL ENGINEE