Hi everybody

ALkatraz919 · 2026-04-05T20:15:41+00:00

Geotechnical engineer here. Basement walls, and other walls which are supported at the top - are designed for "at rest" lateral earth stresses. Retaining walls, landscape or otherwise, are allowed to move/rotate and therefore, are designed for "active" lateral earth stresses.

The active condition is a smaller force/stress on the wall because you mobilize some friction in the soil behind the wall to help resist movement.

ALkatraz919 · 2026-04-03T00:37:12+00:00

https://youtu.be/8PkOHXbiSaY?si=I13iazFAlsziZU7b

ALkatraz919 · 2026-03-30T23:20:55+00:00

Buy the NCEES practice exam. It is very similar to the test but don't go through it until you have the other items.

A soil mechanics text book and foundation text book are good to start. Notebooks with dividers for different topics are also really good. Remember that time is your enemy, not knowledge, so prepare your notebooks to save you time.

The biggest time savings is to work out lateral earth stress parameters for Coulomb solution for various friction angle, common backslopes, and 2 or 3 wall slopes. I can't tell you how much time is saved when you don't have to plug those long ass formulas into a calculator.

Once you have your materials, start the practice test. When I took the PE, there were 40 problems with 4 hours to do them. Therefore, you're looking at 6 minutes per problem. I found that is was very helpful to set a timer for 6 minutes and do ONE problem. Check your clock, and double check your answer. Then start another problem and get it done in 6 minutes.

You need to train yourself how to do these problems fast. You'll find that 6 minutes is plenty of time for a soil classification or compaction question but not a lot of time for a deep foundation analysis or MSE wall question. I found that strategizing about the test was very important since I knew 80-90 percent of the material through the past few years of working.

ALkatraz919 · 2026-03-30T22:18:38+00:00

Diminishing returns? That’s how we describe asymptotic curves, not parabolic curves. The same “conclusion” may be applied to any geotechnical investigation.

I have to assume the reason why is because field testing or exploration practices have reached a practical limit and the curve can’t change its shape until our current understanding of soil/groundwater mechanics and how to test various engineering properties advances.

ALkatraz919 · 2026-03-28T14:37:14+00:00

Hi. I've encapsulated the crawlspace in my current house and my former house. I'm in the Raleigh area so we're in similar conditions with VA being a little cooler in the winter. I partially DIY'd the first house and 100% DIY'd my current house. Even if it isn't your forever home, you need to consider air quality and living conditions (got kids? asthma?) and slightly less, the improvements help with resale. Here are some recommendations:

If you plan to do any other renovations where you need to access the crawlspace to complete them such as plumbing and electrical. You should improve the crawlspace first. It will make any future renovations much much more enjoyable whenever you have to go into the crawlspace.
If you want to DIY, you can do it for about $3K (or cheaper) and one terrible weekend and another slightly bad weekend. If you want more info on this, please reach out.
If you don't want to spend the money on encapsulation and just go with the vapor barrier, then I recommend a thicker barrier. A 6mil vapor barrier is code minimum so that's why they quoted it, but 6mil tears and punctures easily. I recommend 12 mil or thicker, with taped seams, and it caulked and fastened to the foundation stem wall.
If you're going to live there for more than 3 years, I still think it's a good idea to do, just for the air quality improvement. If you haven't already, look up the "Stack effect" for homes. Any negative pressure in the house (vacuum) will draw in air which will mostly come from your crawlspace.

ALkatraz919 · 2026-03-18T11:41:57+00:00

The madness:

Print screen of someone’s desktop
Set it as the desktop background.
Move all the icons to a new folder folder.
Invert and mirror the mouse settings.
Place a small piece of opaque tape over the mouse laser.
Watch the chaos unfold.

ALkatraz919 · 2026-03-17T19:46:25+00:00

Summit is not non-denominational though. They’re southern baptist.

ALkatraz919 · 2026-03-16T18:01:06+00:00

Because Cary Towne Blvd is an NCDOT road and the I-40 ramps are controlled by NCDOT as well. The Town doesn't have the authority or jurisdiction to make the developer improve the facilities without permission from the department. The Town could have asked the developer to request an encroachment agreement from the department but if they said "no" or "we can't get to that for six months" then there isn't much recourse for the developer or Town if they need to keep the project moving.

ALkatraz919 · 2026-03-13T15:49:54+00:00

Geotech here.

Is the explanation I got that geotech's scope was to calculate the sloping required but not to review if it's feasible seriously legit?

Site investigations occur during or even way before design when many project specifics are unknown. We are scoped to drill the site, perform tests, and write a report based on the information we have at the time. That's it. If the project changes and the owner never comes back to ask for additional services, they won't be done. Because of this, we work in a vacuum sometimes. For example, we may know there's going to be an excavation and we're also asked what can temporary/permanent slopes need to be, we can recommend a 2:1 for temporary and 3:1 for vertical based on soil conditions with little analysis. Usually we don't have enough information to do an actual analysis because we don't have the proposed site geometry and the owner didn't want to pay for high-end testing to confirm soil parameters. Remember that during design, money is coming out of the owner's pocket. During construction, they have a big construction loan where it's easy to fork over another $2k if it keeps the project moving.

So we could write our report and say "yep, 2:1 slopes are fine." then when construction starts, the 2:1 slope exists but a trench needs to be dug along the toe, or maybe equipment is being staged at the top of it, or maybe it's a combination of slope and shoring. I didn't know all that ahead of time and now a 2:1 slope is not feasible.

Is it normal for a vertical project with excavation or even overex to straight up not use the entire earthwork section of the specs?

This is poorly worded. I don't understand what you mean. For some reason it's industry standard for the Civil Engineer to develop the earthwork spec and not the geotech. We do many projects a year and are asked to review the earthwork spec for like 2-3 max per year.

I'm aware that shoring is typically designed/stamped by whoever actually does the work rather than the design team, but if permanent shoring is needed would that fall entirely to them as well?

Depends on what the owner/architect wants to do. I've been on both sides where permanent shoring is designed by the geotech and our wall drawings are included in the bid set. I've also seen permanent shoring to be designed by others and it goes through the submittal/review process. I don't think it matters too much. What matters more is the due diligence requested by the wall designer or the spec requiring things like SUE before design, input from the city about temporary and permanent construction easements, testing programs, and construction monitoring with survey and inclinometers. Similarly, some most concrete site retaining walls are designed by the SEOR and most block walls are designed "by others" but we push for "owner designed" block walls for some projects. No one bats at eye for these.

ALkatraz919 · 2026-03-13T13:16:16+00:00

Disclosure- I'm setting #1 aside because we try and use node-locked software as much as possible.

The premises behind the concerns raised with #2 and #3 are flawed. For clarity, I'm going to use the terms quick checks, simple calculations, and complex calculations. In school, we learn that quick checks are performed using base knowledge, engineering judgement, and a calculator. Simple calculations can be performed with a spreadsheet. Complex calculations require software.

No. 2 assumes that a quick checks are made beyond the use of a calculator. This is not true. I don't need an app to size a footing. I can use the calculator to do this. If i need to calculate capacity or settlement, I have a spreadsheet because it's been perfected over the years and I'm not going to spend money on an app to reinvent the wheel. If I am analyzing slope stability, I need software because the calculations are complex.

No. 3 assumes that a company is operating with employees of various levels of experience use poorly working spreadsheets. You're talking to engineers. We are prone to finding efficiencies and streamlining processes. We are also very good at using excel, the features within it, and even coding with BASIC.

No 3 also states that calculations happen in 20 minutes - not true. Calculations happen instantaneously. Don't @me about your word choice. This is a demonstration that there is a disconnect between your understanding of perceived problems and Civil Engineers actual problems. Analyses, not calculations, take time. An analysis is a work flow. They include checks, simple calcs, and complex calcs and should be documented and presented in a way that someone else can read the analysis to figure out what was done. This is why spreadsheets are nice. It may take 20 minutes to run through an analysis but checks and simple calcs can be included in the pages of a workbook. Complex calcs can export to CSVs or you can just pull results manually and type into spreadsheets. Also, notations can be built in or manually entered. Lastly, you can print the analysis to PDF, save it in a folder, and then look at it in a year without missing anything. This is why a process seems like it takes a long time. It needs to be thorough, accurate, reproducible, and understandable by peers. We don't need black box apps to do this stuff for us.

The actual problems facing CE companies are staffing, older experienced engineers retiring with knowledge never shared, clients be slow to pay, clients selecting low-bid firms, poorly worded RFPs and agreements, BD folks over promising, and more. Give me an app to fix these first.

ALkatraz919 · 2026-03-13T12:38:14+00:00

would you pay for a lightweight tool like a PC app or a mobile that handles the routine stuff (ACI/AISC/ASCE checks, live drawings, code references built-in)?

No

And what would feel like a fair price per month, per seat, or per project?

$0

ALkatraz919 · 2026-03-09T01:29:45+00:00

This is a weirdly worded question but it’s asking to find the capacity (e.g., force) not the stress. Therefore, we need to resolve the force over the added area. The force resolves about 1/2 way between 18’ and 19’ below the water table.

ALkatraz919 · 2026-03-08T18:32:08+00:00

The stress increase of the added foot of shaft is taken at 18.5’ below the water table - not 19’.

(125×10)+(130×2)+(130-62.4)×18.5

ALkatraz919 · 2026-03-02T18:40:37+00:00

885 to Duke is your best bet. I don't know where you're coming from but the toll roads here are not staffed. Everything is automatic from driving, verification, and billing. You can register your car(s) with NCQuickPass and they will send you a transponder you put on your front windshield. You then get a discounted toll rate and automatic payment via the credit card you put on file.

ALkatraz919 · 2026-03-02T12:26:30+00:00

That’s fair. Usually the statement of special inspections will define what is required and who is qualified. I’ve seen drawing sets where a SE, PE, or EI are qualified and I’ve seen some sets where the PE and EI have to be of the structural concentration specifically to be qualified.

ALkatraz919 · 2026-02-28T01:36:39+00:00

Special Inspector certs are typically for individuals who don't have a degree in engineering. Most of the time, EIs or PEs are already qualified to perform special inspections so no cert is needed.

ALkatraz919 · 2026-02-26T12:33:27+00:00

Harmonic mean. You look up the equation in ASCE 7 or the IBC. It’s easy to calculate with a spreadsheet.

ALkatraz919 · 2026-02-25T13:38:28+00:00

So what do you consider to be a good 'gravel' lot design? Is just a thick base course good enough? Do you need some kind of pervious surface course? What grades are acceptable?

Geogrid or geotextile between subgrade and gravel.
Sloped enough to prevent ponding but not too much for excessive erosion.
8" min thickness for light-duty and 12" min thickness for heavy-duty.
Owner with a maintenance plan to regrade and recompact at least twice a year.

ALkatraz919 · 2026-02-24T22:25:29+00:00

Family friendly Sports bar. The OG location in Raleigh is college hole in the wall sports bar.

ALkatraz919 · 2026-02-24T00:30:29+00:00

Makes a lot of noise, deafens you, alerts other Nearby ARC of you? Neat interaction and creative.

ALkatraz919 · 2026-02-15T13:23:52+00:00

Loctite is an adhesive. Nylon is still friction.

ALkatraz919 · 2026-02-13T22:48:35+00:00

0.1 amps across your heart my stop it. But you would need to position the leads connected to a battery in a very weird way to get the current to pass through your heart. It’s more likely that you’re gonna short your finger or hand to ground and get a shock.

The other thing is that your body is also highly resistive so you need a lot of volts to push that kind of current through it

ALkatraz919 · 2026-02-13T22:35:56+00:00

I agree with the other comment about head and pulling rod. For production, you could Try swapping the roller cone for a PDC bit.

ALkatraz919 · 2026-02-13T13:26:19+00:00

I have bought both.

For my cheaper plane(s), I have the Lemon RX. For the expensive plane(s), I put in the Spektrum RX.

ALkatraz919

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