Holdfast Training Services Trial Blog

Things are progressing in the usual manner so I’m going to summarise a few of points of interest from over the last week or so. In no particular order.

1. I’ve inherited a Cadet this week. He is an exchange student, currently at the University of North Dakota studying Construction Management. He was essentially dumped in my lap late last week as the Lieutenant who is supposed to be looking after him is out this week. Since I am the only military guy in the office at the moment I went to the airport to pick him up and he is ‘reporting’ to me. Since it was pretty much out of the blue I’ve just been trying to get him inducted, fam’d up on the vehicle fleet, online and then sending him off to the Gym!

2. The slides below were presented at a recent talk to the USACE by the Designer of Record (DOR) for one of the projects here. It is a risk assessment tool. I thought I’d stick it up out of interest for everyone to see as it’s something a little different to what I usually see.

Excerpt from DOR presentation. Step 1.

Excerpt from DOR presentation. Stage 2

Excerpt from DOR presentation. Stage 2

Excerpt from DOR presentation. Stage 3

3.  There have been a few developments at the Central Utility Plant (CUP).  I had an RFI come through about a column mounted Jib crane, which took me by surprise for a few reasons, not least because I didn’t know what a column mounted jib crane was.  A quick Google search sorted that out.  The next issue; there is nothing in the specs about the crane at all, or anywhere else, other than a note on the contract drawings giving direction about minimum hook heights, weight capacities, conformance to CMAA-70 and a requirement to swing 180 degrees.  A cut from the drawing is below:

Excerpt from contract drawings.

Now, Damo has probably noticed that the crane appears to be mounted into the Web of the column; more on this later. Specifically the RFI that I got was to accept a proposed off the shelf solution. It contained some product data and drawings etc and requested that the RFI be sufficient for acceptance without a formal submission. I had a few reservations about this, I had also noticed that the crane appeared to be mounted in the web of the column. And that it appears to be over nothing, even when cross referenced with other drawings. I sent a question to the client asking what the intent of the crane is but have thus far heard nothing. Nobody here seems to know what its for either.

The designer reviewed the RFI and had no issue with the actions that the crane would impose on the column but I still had misgivings, specifically with regards to how the Contractor was intending to mount the crane (welded plate I guess) and maintain the 180 degree reach. I therefore asked for a formal submission with the connection details articulated more clearly than a manufacturers drawing which, in my opinion, won’t work as required. I spoke with the Contracting Officer’s Representative about this because the designer will be able to charge to look through the submission because it will be out-with the originally agreed submission requirements.

4.  Specialized (sic) Engineering are the QC sub-contractor that conduct tests such as concrete slump, soil compaction, weld integrity and the like.  For my structure they are required to come and check bolt tension, weld and plumb of the building.  The most interesting thing, for me, of the last Specialized visit was the apparatus used to test the plumb.  The Bazooka bob is an enclosed steel tube with a string tied at one end and measured increments at the other.  It extends out and attaches to the steel magnetically.  It is 10’-5” with increments of measurement of 1/8^th of an inch at the base.  A measurement of 2/8” at this distance represents the 1/500 allowable deviation from vertical so if the string falls outside of this you know that the column is deficient.  Simples.  All the measurements taken on site were within tolerance.

5. The cooling towers (a mechanical feature which will eventually sit in the CUP) submission is being bounced around from Principal Contractor to USACE to Client to USACE to…   The proposed towers (by the Principal Contractor (PC) were submitted a while ago and returned as deficient with c. 21 comments.   The PC re-submitted the same towers with, what I consider, rebuffs to the client comments. I was in a meeting yesterday where the client essentially ‘kicked off’ at the situation questioning why it was that clearly erroneous submissions were being sent in, especially since the crux of the issue is that the cooling towers proposed are so far away from the Basis of Design (BOD). Again the PC had an answer along the lines of “we can ask for a variance to the BOD,” to which the client pretty much said “provide what we ******* ask for in the specs.” Fair enough – it was a heated meeting.   This is interesting, not just because of how stubborn the PC is being but also because the cooling towers in the BOD are anchored to the steel building at 12’ centres. The PC preferred towers are anchored to the building at 14’ centres. You can no doubt guess at what spacing the steel frame has been erected, snapped, decked and welded.

6. Another BOD issue; I am lead LEED representative at the moment whilst the actual lead LEED lady is on maternity leave. (LEED is essentially the same as BREAM). I have split responsibilities with another guy from the office who is also here temporarily. I reviewed my section (recycled content and regional materials) and had a scan through the rest of the submittal before passing the it to the other guy. I noticed that the PC had made a comment that they were making no effort to submit the 3^rd party VOC certification required by the specs for Environmental Air Quality because the material suggested in the BOD didn’t come with it as a matter of course. I gather that they got this information from speaking to the manufacturer named in the BOD. I advised him to ‘E code’ (re-show) the submission and request the PC to send of material to a 3^rd party lab for testing and certification. What interested me about this was that the material and manufacturer named in the BOD wasn’t compliant with the specs as a matter of course. I am waiting out to see if the PC gets back to me on this issue or if they will just send the material off for testing. The cooling towers issue hints at the former.

7. Another area of contention has been due to backfilling activities (and I mean to echo Guz’s sentiments about good and bad engineers, but also add in ‘Lucky’) For me the issue started when I spotted a sub contractor backfilling some utilities into fairly wet excavations. What didn’t help was that there was water ponding in the weld pits and there was no effort to remove it prior to backfilling. To me this seemed ‘a bit weird’ as a gut reaction although admittedly I wasn’t clued in on the method of backfilling in the specs. I made a call to the PC and said I think the water should be pumped out of the weld pits as a minimum, prior to backfilling, and went to lunch. When I got back from lunch someone from the mechanical team came up and shook my hand for a ‘good catch.’ Apparently what I had witnessed was out of spec (shock) but also another in a long line of deficient practices with respect to the placement of utilities. Whilst I was at lunch the civils project engineer went to have a look at the site, taking along with him 2 other QA reps and some of the mechanical team. The PC superintendent noticed the collection of people and called his QA team . The PC was requested to prove that they had been backfilling properly to which one of their team jumped into the excavation and promptly sank in soil, which was presumably not within 3% of the optimum moisture content called for in the spec. This is an ongoing issue which could well form the basis of a TMR but the point I make here is to echo something I am sure I have heard around PEW but I cant attribute it to anyone in particular; if something doesn’t look right, it probably isn’t. I was fortunate to be passing by the activity when it happened or it mightn’t have been noticed.

In other news:  This.

Firstly – Nice job Guz, Swimmer and Fat-Bloke.

The Coffee CUP is nearing completion of sequence 1 / 4 structurally.  In the main things have progressed smoothly, with the odd schnell evacuation due to the recent thunderstorms.  Minor glitches include the incorrect placement of anchor rod bolts which attach the baseplates of the columns to the rc pad foundations.  This was a quick fix with the erroneous bolts cut down to the profile of the bottom of the base plate (essentially so the base plate was resting on top of the cut down bolts) and new HILTI bolts epoxied into newly drilled holes in the correct location.

Sketch of Baseplate anchor rod correction

The washers used at the base plate location also need replacing with larger ones so that they entirely cover the drilled holes in the base plate.  This will allow any uplift forces to be properly distributed to the baseplate through the entirety of the washer.

A more serious problem arose at the placement of a double bolted connection.  A double bolted connection is essentially a shared connection between two beams on opposite sides of a single column.  This is a fairly common connection type however the method of erection is supposed to be controlled for safety reasons.  This is stated by the Occupational Safety and Health Administration (OSHA) para 1926.756 and also in the USACE HQ document EM385-1-1 at OSHA and EM385-1-1 (Cl 27 E)

Erection in a manner contrary to these documents is essentially illegal so in order to prevent the issue correct erection methods are stipulated in the contract documentation (spec) and checked for in the steel erection plan submittal which is required by the government before work can start.  In cases where shared connections exist there are three standard ways of staying compliant with the regulations.  These are sketched (crudely) below but are 1.  Cut outs in the end plate. 2.  Staggered end plates. 3.  Welded or bolted shop or field attached seats.  These methods are designed to either support the first beam directly or by allowing the minimum single snug type nut and bolt to remain in place whilst the second beam is flown into position.  This removes the risk of the first beam slipping its connection and falling during the process.

3 methods of fabricating for double connections

On site the majority of the shared connections are staggered (pic 2) to allow for this method of erection, however some have neither a cut out in the end plate or staggered base plates.  When asked exactly how he had placed the beams the subbie admitted that he had removed the nut which had been placed after the first beam had been flown in and one of his lads had stuck his spud wrench through one of the other bolt holes.  Highly naughty.  We chatted about the situation for a while and figured that there must have been some sort of detailing error because it made no sense to not stagger the connection plates, and even less to not detail a factory fitted seat.  Since he was the sub contractor I am not supposed to give him direction, unless it is an imminent safety issue, so I had to speak with my counterpart at the Principal Contractor in order to resolve the issue.

I went back to the office and was able to corner the resident steel expert who pointed me to the US American Welding Society document D1.1.  This thrilling tome has within its many many pages a calculation for the strength of a fillet weld which is basically a function of the area of the weld and the grade of steel of the rod that is used during welding, with a factor of safety thrown in.  I was able to assess from the field drawings what the heaviest beam would be in the whole construction and based my calculations on this.  I proposed a 1” x ¼ “ fillet weld which could be applied in the field to the first beam that was flown in.  This would be more than sufficient to hold the beam in place whilst the nut was removed in order to fly in the second beam.  Obviously my proposal was only a recommendation and the actual design would need to come from the Principal Contractor.  I highlighted this to them and requested that they submit an RFI for the field solution so that an audit trail would exist.

My proposal was questioned with an air of refusal by my counterpart who said that she had spoken to her manager who didn’t see the problem.  A quick scan through the necessary paperwork, including EM385, the Specs and the Steel Erection Plan and a face to face with some relevant paragraphs printed out highlighted the government’s position.  The issue remains unresolved as we wait for the RFI but the last I heard the Health and Safety guy had waded in and written a deficiency.  This takes the issue in a more ‘formal’ direction which I had been trying to avoid.

Incidentally – I tried to find a similar clause in CDM but didn’t get on so well.  Does anybody else know if there is one / where it is?

In other news – my wife and I went on a road trip to Niagara falls. Wetter than an otters pocket.

I also navigated one of the more arduous ‘trails’ in typical local attire fuelled by suitable amounts of coffee.

Standard US hiking Garb

Work continues on site at a fairly decent pace and there is much focus on the project interfaces especially now that the Notice to Proceed (NTP) has been given to the third project on the site.  There is talk at present about the selected construction methods for the project I am working on with regards to the erection of the structural steelwork.  This will form a part of the central atrium and will ultimately be the architectural feature of the whole building.  At present the proposal is that as the steel columns are placed they will be tied from the outside of the building until the relevant roof truss section is placed and the element of the frame becomes self supporting.  However due to delays on the adjacent project and subsequent efforts to make up the time they now require the space where the ties were supposed to go.  This means that either 1.  The ‘ties on the outside’ idea will now have to become a ‘struts on the inside’ idea to accommodate work on the façade of the adjacent project. 2.  Shift work.  This is still very much a work in progress.

Away from the structural steel side of life a recent check on one of the columns revealed that the lap length was insufficient.  Initially this was spotted by comparison to the contract drawings, which have a little table showing the required lengths based on steel type (60,000psi or 75,000psi) and diameter.  This makes QC fairly easy.  The specified length was 63” however only 54” was measured.  The root cause of the issue was a sequencing error on the part of the contractor.

The column in question was a central column which had tie in to two elevated two way slabs at differing levels and the RC beam which forms a part of the monolithic frame of the building.  This means lots of steel.  The general idea can be seen in the diagram below – which is a general detail with the column rebar drawn in red for clarity.  DEFINITELY NTS!

As you can see the lap measurement is intended to be from the base of the lower slab.  Because of the ATFP requirements and the amount of steel required in the beams my suggested sequence would be to place the steel cage for the column and construct the beam through it.  In this case however the steel for the beam was placed, and then poured with starter bars left protruding for the column cage to tie in with.  This reduced length is obviously insufficient and outwith the specification.

The error was immediately highlighted to the Principal and sub- contractor who were informed that they couldn’t close up the formwork and must put a hold on the following day’s pour.  This obviously meant knock on delays to follow on slab pours.  The only way forwards that I could see was to strip out the pour and start again, at huge cost in time and money or to lengthen the bars by welding, couplers or some other suitable method.  I spoke with one of the other Project Engineer on site who checked the measurement and agreed that the error was too far out and we discussed a way forwards to try to minimize the delay.  We looked at the lap length specified and he suggested looking to the Codes for a way out – specifically ACI318-11 which is the US version of the BS EN1992:1-1:2004.  I broke out into somewhat of a cold sweat at the suggestion and was just about to propose ironing certain parts of my anatomy as an alternative but when he started to take me through the codes and to the relevant section on ‘splices’ I noticed that the code seemed somewhat user friendly – it even has a commentary section.

Excerpt from ACI 318

There is still the whole Eurocode-esque requirement to flick back and forth between referenced clauses, however in the e-version of the document these references are hyperlinked, so switching back and forth between clauses is somewhat less of a naus than the frantic wheel scrolling endured on the design exercises.  Anyway – the calculation for the splice length is quite simple, just 1.3 x the calculated development length because this sort of splice is a Class ‘B’.  In true Code style though, the development length calculation was almost an impenetrable mash of greek symbols.

The commentary provided useful direction and actually most of the factors are taken as 1. So it can be seen that the development length is actually a product of Fy, Fc and bar diameter.   In this case though I knew what the actual length was; I knew what strength steel we had and the bar diameter and so I adjusted the strength of the concrete until the calculated length matched the measured.  This solution was acceptable, just about,  based on restrictions in the design code about the acceptable strengths of concrete that could be used.  It was calculated that a 10,000 psi instead of the 60,000 specified concrete would suffice.   The proposal was obviously sent to the designer for their approval, which came back fairly promptly to proceed with the higher strength concrete.  In the end the pour was only delayed by around two days, and now there are some super strength columns in the structure so everyone was fairly happy.

In other news we have a birds nest in our garden which has become the focus of some evening entertainment.  So far the attrition rate of the chicks is around 50%.  We are not sure if the two that we found lying dead on our patio were pushed by the other two, or if they just fell but at present king of the ring is a fairly brutal affair.  Also, me and Danielle went to the tallest waterfall in Maryland.

This weeks thrilling instalment follows on (inadvertently) the theme set by Guz and Olly.  Apparently.

I have just completed my transition week, which now sees me as a Project Engineer out of an Area Office (a more familiar construct for those who have been / are in the US) working on two projects and also minor obligation back to the PM and PrM Office running the contract I have set up.  As will be usual for most I had to undergo a site safety induction, ran by the principle contractor of the site on which I will be spending most time.  With reference to mine and Henry’s last comments; the brief was actually fairly impressive and many of the standards that are in place are similar to those I experienced in the UK, with a few exceptions (so far – The rickety ladder of doom, no requirement for banksmen for reversing vehicles, gloves optional unless doing specific tasks)

Site itself is fairly dynamic and its not unusual for it to be almost unrecognisable from one visit to the next, particularly with concrete pours; movement of fill material from one area to the next to facilitate access; creation of new haul roads etc.  This will only become more disorienting with the award of, now, two new jobs on what is already a complicated and congested site.  An area that I am tracking is the interface between two projects, one of which is responsible for the placement of services and utilities in an area which falls within the new project’s Limit of Disturbance (LOD – AKA a boundary).  This is an interesting issue because there was a change order submitted to accelerate the placement of the utilities months ago, however this was cancelled when the schedule for the new work was reviewed and it was seen that no work was going to take place until after the utilities were originally scheduled to be placed anyway.  So, a requirement was included in the contract for the two Principle Contractors to de-conflict activities where there were pinch points in LODs.  There are now mutterings however that the principle contractor on the new job (who is apparently very savvy when it comes to working with the government) is expected to submit claims to the government due to a change in site conditions, which precludes him from going into an area that he doesn’t intend to go into anyway.  Good!

On a more real time issue, myself and another Project Engineer inspected a deficiency yesterday on a basement structural RC beam.  It is still propped and not fully load bearing yet however there is a large crack running pretty much the length of the beam (c.3.5m) which varies from around 300mm wide in places to c. 50mm and is deep enough to expose the reinforcement.  (For Damo’s amusement I have attached a Sketch)

There is significant bowing to one side of the beam which seems to indicate that the formwork has failed which has allowed concrete to pour onto the floor below and caused the deformation of the beam.  The deficiency has been highlighted to the designer for inspection and comment.  I expect that there will be a requirement to chip away the majority of the side of the beam where the deficiency is and either replace the concrete around the existing pour as is, or epoxy some steel dowels (form savers or similar) and replace the concrete.  There may be some practicality issues with this solution as the beam is obviously supposed to be flush with the floor slab.

Other ‘interesting things’ I have seen:

1. Mixing of red dye into concrete surrounding some electrical utilities so that any future workers will be able to identify what they are potentially about to dig through.  I thought this was ingenious – is it common practice: have I just completely shown myself up?!
2. The way that schedule changes affect the engineering of a job. The basement slab has not yet been poured due to weather delays and a desire to get out of the ground.  Therefore the basement walls (essentially now cantilevered) have been extended in order to resist the moment imposed due to the active lateral earth pressure
3. The utility of a road traffic sign (presumed stolen) as part of some pretty sketchy looking formwork. It was only a pour below knee level or so, and was not structural.
4. An excavator, almost excavating under itself as it sat atop some fill material, which was clearly exhibiting signs of face slippage. I highlighted this to the Engineer I was with (Geotechnical background) but he didn’t seem bothered.  Apparently if the Operator were to ‘feel it going’ he would simply put his bucket down to the ground.  ‘They’re pretty quick off the mark with those buckets.’ Good to know.
5. Slump testing concrete at point of arrival and point of placement. There was a bit of pushback when this was spotted in the specification from the designer, however they would not budge.  Personally I can see the utility for pumped pours where some slump is gained after pumping.  For one, any sub-standard batches are caught before the pumping begins, for two, any batches that are close to the limit (4”-8” in this case) at delivery can be verified at placement and the requirement to return a batch ‘just to be on the safe side’  is mitigated.  This is important where timing is critical, especially on larger pours, when the formation of cold joints in the slab is a potential issue. (seen before on the site)
6. Construction sequence affecting design – whereby holes have been left in the first floor slab to allow for stores to be lowered into the basement at a later date when the basement slab is eventually poured.  This has meant additional reinforcement requirements at the corners and the placement of form savers to allow rebar to be placed across the void at a later date (screwed in) to allow continuity.  Also – similar gap exists adjacent where the tower crane currently sits.

I also attended a webinar event ran by the NCE titled ‘Building the Age of Resilience.’  It pretty much took the form of plugging the following product (which I have never heard of) : www.globalcalculator.org

From what I can gather this tool enables the user to postulate future global scenarios of energy requirements, industrial output, global consumption of meat, fuels and goods etc and simulate the effects on global temperature.  This video https://www.youtube.com/watch?v=2_6flonHN0o is a brief tutorial on how to use the tool but it’s fairly self-explanatory.  From what I can gather unless you are the CEO of a company trying to assess some strategic direction, or the Prime Minister then it’s really just an interest thing, but it is actually, sadly, quite interesting!  I guess if you are trying to assess the future impact of a single project you could potentially (at the concept stage) adjust a single ‘lever’ and see if the economic impact to the project is worth the engineering effort?  Perhaps.

Contract Stuff

Last week I intimated that there was a potential issue pushing a new contract through the procurement process in time before the base contract to which it would be attached expires.  At the start of the week we got confirmation that the course of action we pursued was OK with the KOR and I received verification that I could have the funds fairly quickly, which was good.  My week then spiralled down into deep, dark, depressing realms of frustration, repeated work and government bureaucracy.

To relate everything I have been required to do will induce eye-stabbing levels of boredom in the reader, and no doubt some level of confusion.  I will therefore ‘paraphrase’ and highlight key points.

One of the many hoops I have to jump through along the procurement process is an Independent Government Estimate (IGE) which is essentially a method of making sure that the contractor isn’t ripping us off.  This is a fairly important part of being responsible for spending tax dollars on behalf of the taxpayer.   Using the Scope of Work I produced I was able to attribute a level of staffing that would be required to fulfill the  requirements of the scope and, using pre-negotiated rates from the base contract, attach a cost.  In parallel to this I sent a Request for Proposal (RFP) to the Contractor who did the same.

When I received the proposal back from the Contractor I had to wait before I could open it because I still had to get sign off on the IGE; to open the proposal prior to this would be illegal.  Office policy dictates that if my IGE and the Contractor Proposal are within 10% of each other I can combine the next stages of the acquisition process into one.  Fortunately, when I was able to open the proposal, the bottom lines read within 6% of each other.  This meant that I could accept the proposal, no questions asked – as long as I could justify and explain the minor discrepancies in a document called the POM/PNM (this document goes against every JSP101 principle and is judged by weight, not content).  On the face of it I could quite easily justify the discrepancies, however when I dug into the weeds I found that the pricing strategies used by myself and the Contractor were wildly different.  The overall level of effort was essentially the same, except it was allocated to different task lines.  This was a bad thing as it meant that the acquisition would have to go through a negotiation stage, which we don’t have time for.  Fortunately, one of the experienced contract officers here recommended that I simply conduct a “scope clarification conference” with the contractor*.

At this juncture it is important to note that negotiating with the contractor without first sending a copy of the Pre-negotiated Objective Memorandum (POM) through the District office is against official policy, however if you call and clarify the scope with him and he sends you an entirely new proposal. Well, that’s fine. Happily the scope was a lot clearer to the Contractor after we had negotiated had our scope clarification conference and I received a second proposal, for a similar amount but broken down in a similar way to the IGE.

Now, the other aspect of this is deciding what pot to pay for the services from.  In order to put the scope together I had canvassed opinion around the stakeholders in the various offices as to what level of effort they would require for the period of performance so that I could write a suitable SOW to meet their requirements.  However when I called a Purchase Request and Commitment (PR&C) meeting to discuss the issue of paying there was a huge reluctance to stump up the cash!  Issues varied from just not having budgeted for what was requested (then I’ll adjust the SOW and you’ll lose your scheduler) to suddenly realising the costs involved are too high to justify.  Fortunately for me there was an adult in the room who was able to bat away some of the niff naff poor drills excuses and so the meeting was actually really useful, and there was resolution on who was paying for what…as long as I adjusted the SOW, IGE and POM/PNM…

Lessons –

1. The importance of an absolutely watertight scope from the outset, written in consultation with the key stakeholders.
2. The importance of lining your funding sources up. Always figure out who is going to pay and then hold them accountable.
3. The importance of not leaving anything contractual to the last minute, and then trying to rush task orders through to buy more time to deal with them.
4. The sheer amount of interpretation that goes on with regards to rules and policy. This is where the area managers earn their crust and put their head on the block.

Health and Safety Stuff

I echo Henrys sentiments with regards to Health and Safety.  I have been on site twice now (not bad in 2 months) and have been assigned some more site based responsibilities.  I will retain responsibility for the contract I am setting up, including running it once it’s/ if it gets through, but I am also shortly to be a Project Engineer on 2 projects.

In outline I am working on a site that is home to (currently) three large scale construction projects; all part of the same programme in all but funding; at various stages of construction (from 0 – 30% project completion; 0 – 90% structural completion).  I will be working on one that is around 7% complete (out of the ground and having cast in place concrete pours on level 2 presently) and one multi level parking structure that was awarded to the principle contractor around 2 weeks ago.  This is due to break ground in c. July.

On my walk around I noticed that the method of access to the second floor slab of one structure was by a wooden ladder, no handrails, which seems to have been erected by a class 2 chippy.  There was no method of holding on, other than to hold the rungs, and no tie down at the top or bottom! Good.  The edge protection, whilst similar in height to UK spec was also knocked up by the same chippy.  There has been a recent revision by the Department of Labor (sic) and Occupational Safety & Health Administration (OSHA) which has placed more stringent measures to site working practices.  This might well be a blog in itself.

Chartered Engineer – Professional Engineer Stuff

I have been chatting to the US engineers out here to get a flavour of their ‘route to chartership.’  I won’t go into details for fear of this tome getting even more tomier, but the interesting comparison to draw between the US and UK is that US Professional Engineers (PEs) are pretty much ten a penny out here, compared to the UK, where I gather a Chartered Engineer is rather a rare beast?

And also,

Myself, Danielle, Henry and Jo enjoyed Intercourse immensely.  I would highly recommend it to anybody who visits.

Pun intended.

The sports model.