I think that you may be referring to the Scope 6.1 (Part A General Requirements).
The requirements for continuous inspection vs periodic...Hmm, I'm not sure that I have ever seen that spelled out in D1.1, I usually find those requirements in the job specifications and the EOR assigns responsibilities to the inspectors.
I agree with John, you won't find any defining or assigning of work as to Continuous vs Periodic Inspections within D1.1.
There are some things of interest in AISC especially the Seismic Design Manual (Appendix Q5.1.). Also in many other training and reference books. But not D1.1.
The chart or information generally included on the Structural General Notes comes from IBC Table 1704.1 I believe (don't have it here at the moment). They will generally have inspections criteria in the Job Specifications as well.
Have a Great Day, Brent
D1.1: All welds shall be inspected.
I don't have my book in front of me, but I believe it is clause 6.9 in D1.1:2010.
That begs the question: what edition of D1.1 is imposed by the contract, PO, drawings, building code, etc.?
Al
Correct, it's the same as far back as 2002 edition:
6.9 Visual Inspection
All welds shall be visually inspected and shall be
acceptable if the criteria of Table 6.1 are satisfied.
I agree. But the question was as to a distinction and code defining of Periodic vs Continuous. Which defining D1.1 does not make.
I know that therein is the basis for quite a discussion. It is one that many of us find inadequate when classifying inspections into these two categories. Mainly because we agree that on a job of any size, Periodic means on the site and making rounds all the time anyway. How is that any different from Continuous?
But, according to IBC 1704 Table 1704.1 there is a difference. It all sounds like a bunch of symantics to me. The question will actually still be a matter of how much the customer/engineer/Building Official Having Jurisdiction/etc wants to spend and thus how much time you will get to be there.
There are certain parts of the job that we can easily justify having at least one inspector on site continuously. But, there are other parts that the customer will get to say how often he wants us checking up on the quality of the project.
Another part of this equation that bothers me is that because the specs almost always specify field TPI inspections many erectors don't have an actual in house/field inspector on site. They relegate all QC/QA to us. This should not be. Since it is, we could press the issue of needing more time since the contractor is not doing his job properly.
But, the OP's question still was as to a D1.1 distinction of what work was classified Continuous and what was classified Periodic. To which I still feel John is correct, there is none. Only that all welds will be visually inspected.
Have a Great Day, Brent
OK, you may periodically inspect 100% of your welds or you may continuously inspect 100% of your welds! I fail to really see the difference?
>OK, you may periodically inspect 100% of your welds or you may continuously inspect 100% of your welds! I fail to really see >the difference?
This^^ is true.....but.....
The difference is in the ownership of the welds that were placed.
The TPI doesn't have to inspect every weld if his contract specifies periodic vs continuous.
"Symantics".... as Brent said, and there is a difference, but D1.1 doesn't spell all of that out...it has some mealy words in Clauses 1.4 & 6.1 about the Owner and EOR assigning responsibilies for those inspections on his/their behalf.
John, I am not real familiar with D1.1, in fact until a couple of years ago, I had never used it as a working standard. I am on a very steep learning curve and have had some very hard lessons taught to me on this standard. Clause 1.4 does state "shall" which according to 1.3 something, is then left to the engineer to change or is more or less mandatory for contract inspection? 6.1.2.1 states:
6.1.2.1 Contractor’s Inspection. This type of inspection and test shall be performed as necessary prior to
assembly, during assembly, during welding, and after
welding to ensure that materials and workmanship meet
the requirements of the contract documents. Fabrication/erection inspection and testing shall be the responsibilities of the Contractor unless otherwise provided in the
contract documents.
That sounds like 100% continuous to me?
You're right but this the owner of the weld---"contractor"(whomever is placing the welds) must inspect 100% of their welds, this we agree on and D1.1 is clear about. But if a third party inspector(usually hired by the owner of the project) is contracted to perform inspection, they have a contract and agree on periodic vs continuous.
ie. Take for instance a job going through my shop. I'm responsible to inspect 100% of our welds per D1.1.
But a TPI, hired by the owner, may be only doing periodic inspection. He may drop by our shop and look at a few pieces one day and then I may never see this guy again(unless there are issues that pop up later) for the remainder of the time that job is going through my shop.
Then again, if he has continous inspection, he camps out on my doorstep and watches every piece travel through our shop from receiving to loading the truck for shipment to the jobsite.
And to many of the rest of us...Just try getting authorized to spend that much time on their job and taking sssooo much of their money.
MONEY...That is the bottom line. Notice the majority of my post supportted the position of really needing to be there and at least being able to justify what they term continuously in order to properly carry out periodic inspections. But both the erector who is trying to hide things and make time on the job and the customer who sees us as a code stipulated necessary evil money pit will do all in their power to see that you are only there 1/2 as much, or even less, than most of us would like to be.
I actually love it when a larger crew will have to have me there continuously while they do moment connections, which they will all acknowledge as being Continuous, but they only put one man on the welding of the moments so I have lots of time to watch everything they are doing; fit up, tacking, pre-heat, welding, etc. And I don't mean just at the moments, though they get extra attention since there is only one guy doing them. I can keep up with the whole job. Actually, once the erector gets used to that, they love it. They don't have to worry about leaving some area for me to see at my next periodic. I'm there, have seen it, already signed off on it, just keep going. And if they have any questions, I'm right there. Only hold up is if we need an RFI to cover something because it is out of my scope to make a call.
John beat me there... and in regard to that, it also depends upon rather it is a shop TPI job or a field TPI job. Then it will also have to take into account if the fabricator is a Pre-Approved shop.
Have a Great Day, Brent
John, Brent - thanks for that! I think I see your argument now and also my mistaken interpretation!
OOHH, I don't think I would totally call it a mistaken interpretation. It all depends upon who is interpreting it and who is taking who's money and how much of it.
But, the customer will usually win...the project loses for lack of totally complete inspections with contractors who we know love to bend, if not totally break, the rules. And, we then are in an hazardous situation trying to make sure we have covered ourselves as well as the public from both contractors and customers who don't really care.
Have a Great Day, Brent
Brent, I was referring to the difference between contractor inspection requirements and TPI inspection requirements as pointed out by John, which I had mixed up! But thanks for your confidence!
I suppose I am in an enviable position were money has little part in the inspection process. All our AWS D1.1 parts are 100% continuously inspected both by the client and the contractor. This seem's to be the norm in my particular field at the moment although I can imagine this is not the case in most situations?
46.00 it's all good...I was hoping to explain my view well enough in typed words that it all made sense to someone reading it.
continuous = tpi is full time stationed at fabrication or erection site
periodic = tpi visit is as per request or on-call basis required for particular inspection
this arrangement is normally as per agreement between contractor and the owner
I believe you may need to reference IBC and AISC documents for those terms.
If you’re serious about the quality of your products, pre-shipment inspections can help you achieve the quality levels you’re looking for. To do the inspection, an inspector will go to your factory in China once your order is about 80% completed.
By SWN1158 
Date 09-13-2019 10:34
Edited 09-13-2019 18:45
The original post is over two thousand days old, but in looking through the responses, it doesn’t look like the question regarding periodic and continuous inspection was clearly answered. I believe this is in reference to Chapter N of the AISC Specification for Structural Buildings, which was added to the manual in 2010. This chapter includes six tables (N5.4-1 thru N5.4-3) that list inspection tasks prior to welding, during welding, and after welding, and inspection tasks (N5-6.1 thru N5-6.3) prior to bolting, during bolting, and after bolting, and they indicate which inspection tasks are "O" observed on a random basis, and "P" performed for each welded joint or member, and for each bolted connection. These are applicable when AISC requirements are specified in the contract documents.
I think Joe is on point. AWS D1.1 is not a stand lone code; it is actually rather low of the totem pole. There is a hierarchy to the codes that are applicable to building construction. The state building statue is at the top. It references a building code which in the case of steel construction references the AISC Steel Construction Manual and Code of Standard Practice. That in turn references AWS D1.1.
In my case, in the past, the state building statue references two editions of AWS D1.1. It references AWS D1.1:1988 for ASD and D1.1:2000 for LRFD. The state statue gives the Engineer the authority to invoke a more recent edition of AWS D1.1 when he determines is appropriate.
The building code may include mandatory inspections of specific weld types; such as multiple pass fillet welds larger than 5/16 inch and CJP groove welds loaded in tension, etc. In many cases it is a third party that performs the mandated verification inspections. The extent of the verification inspections and the duties of the verification inspector are defined by the Statement of Work completed by the Engineer as part of the permitting process. In other words, the building official having jurisdiction has a say in the extent the verification inspection. The building official is responsible to verify the Statement of Special Inspections include all the mandated inspections as well as any additional inspections he feels is needed to ensure a safe structure.
It isn’t the verification inspector that determines the extent of the inspections required. If and when there is a question in that regard, the verification inspector and Engineer should discuss the details and the extent of verification inspection required. I would not be surprised if the extent of the verification inspections changed if it was demonstrated the contractor did not have a functional quality control program in place.
As a rule, I ask for a copy of the contractor’s quality control manual and verify whether or not the contractor has implemented it. It is usually relatively easy to determine if the contractor has a functional QC program. If the QC program is not functional, it is not unusual for the Engineer to ramp up the verification inspection performed by the TPI. In other words, the TPI may be directed to assume some of the duties the contractor should be providing. Again, it is the Engineer that dictates the level of verification required to ensure the requirements of the design drawings are met.
It is important for the verification inspector to understand the extent of the services he is to provide. And since it is common for the situation to be fluid, i.e., it can change day to day, it should come as no surprise that the level of inspection can change.
The importance of a well written report cannot be overstated. Over the years I have heard a number of inspectors make the claim the Engineer did not support them when the inspector reported non-compliances. I can understand why in some of the cases. The reports were incomplete and did not provide the level to detail needed to make a good engineering decision.
A report that includes a statement that the weld was rejected due to unacceptable undercut does not tell the Engineer which member or fitting exhibited undercut or how deep or long the undercut was. The Engineer is not going to jump into his car and drive across town or across the state to see how serious the situation is. He more than likely will side with the contractor because there is insufficient information. The Engineer will assume the contractor’s QC accepted the weld and it is a simple disagreement between inspectors, in other words there is nothing to be concerned with. In a similar manner, a statement that the weld profile is unacceptable is insufficient information for the Engineer to make a reasonable decision on whether the weld needs to be repaired or if it is “good enough” for the application. The situation could be very different if the report included a narrative, dimensions, and photographs of the welds that are in question.
As the inspector, it is important to CYA. I always include the basis of my inspection, i.e., the name and project number of the structure, the extent of the inspection is as per the Statement of Special Inspections dated CYZ, the drawings used were bba, rev. Q, stamped "Approved for Construction" dated ccddee, the design based on ASD, the applicable structural welding code was D1.X:20XX, etc. The first page of my report lists all the back ground information. It is the second page that lists the actual member inspected with a listing of the offending fittings. Any member listed by the report as noncompliant lists the specific fitting that is noncompliant and the nature of the "defect." I also include a photograph of the "defect" in the report and where possible, I include a ruler in the photo to provide a sense of scale. The details included in the report vary from project to project, but there is basic information that should always be included. A check list or preprinted format will mitigate the chance of the inspector forgetting to collect certain bits of information.
Do not under estimate the influence of a well written report. It is the product each of us "sells" to the client.
Best regards - Al
I love this forum, I always learn so much.
