What is an injection record?
An injection record is the account of resin or grout injection carried out on one defect: where the defect is, what was done to it, which product went in and how much, who did the work, when, and what it looked like before and after. In a tunnel the defect is usually a leaking joint, a leaking segment, a wet crack or a gap, located by tunnel drive, ring number and clock position. The record is what the engineer relies on to accept the repair, what the main contractor hands its client, and what anyone checking the work later goes back to. A record written up from memory at the end of a shift, or rebuilt from photos on several phones, is weaker on every one of those counts. The strongest record is captured once, at the defect, by the person doing the work, while they are doing it.
What should a defensible injection record contain?
A defensible injection record answers the questions an engineer or auditor will ask without anyone having to explain it. Where: the tunnel drive, the ring and the clock position, plus the defect type and the engineer's instruction. What: the packers installed, injected and patched. With what: the product, drawn from an identified kit with its batch number, and the litres used. Who and when: the person and company doing the work, and the date the work actually happened, kept separately for each visit. Proof: a before photo and an after photo, each tied to the defect and its time of capture. Acceptance: who validated the work and when, or why it was sent back. History: every change in order, including rework. Each of these is a field in DEFECTED, filled in on the phone at the defect, not a column completed later in an office.
- Location: tunnel drive, ring number, clock position, defect type
- Packers: installed, injected and patched
- Product: the kit it came from, the product, the batch and the litres
- Work sessions: who, which company, which day, and what changed in that visit
- Photos: before and after, with the capture time burned in and the location attached
- Validation: the engineer's decision, name and time, and any send-back comment
How does DEFECTED count packers?
Packers are counted on the defect in three figures: installed, injected and patched. The crew updates the counts as the work goes, and the defect carries the running totals. Each change is also written to a work session, which records the difference that visit made rather than the total, together with the person, their company and the date in the project's timezone at the moment the work was recorded on the phone, not when it later synced. That is what lets daily production be attributed to the day the injection actually happened, even when the phone was out of signal until the next morning. If a defect is reopened, the work after reopening starts a new session, so the original visit stays as it was and the rework shows as its own entry. The engineer sees every work session on the defect before deciding whether to validate it.
How is product traced to a kit and its batch?
Product is drawn from a kit rather than typed in as a free figure. A kit is opened in the app with a photo of its label, the product, the batch number, its size in litres, and who opened it and when. Every draw from it is logged with the litres, the ring, the clock position, the time and the person, against that kit. Litres remaining are never typed in: they are the kit's size minus what has been drawn, worked out the same way on the phone and on the server, so the two cannot disagree. A kit finishes on its own when it reaches zero, or by hand with the leftover recorded as waste. The app warns when a kit is low, and flags a kit whose logged litres differ from its size by more than five percent, so product use can be reconciled against what was opened on site.
The products a project picks from are set in one list. Today it holds acrylic gels, such as Normet TamAcryl 4000 and the MC Injekt GL95 range, and PU resins, such as Normet Tampur and MC Injekt 2111 Flex Exo, each labelled with its class so a new operator does not have to know the brand to log it correctly.
What makes the photos usable as evidence?
A photo is only evidence if it can be tied to a place and a time. In DEFECTED the capture time is taken when the camera returns the image, never when it uploads, and it is burned into the pixels in the project's timezone, so every viewer sees the same time. Each photo is taken from inside the defect it belongs to, as its before or after photo, and is shown with the tunnel, ring, clock position and defect type, rather than collected in a camera roll and matched up later. Done only unlocks once the after photo is attached. Photos are resized on the phone to a size that still shows the defect clearly but uploads quickly on a weak connection, and they wait on the phone, in a queue that retries rather than drops a failed upload, until there is signal to send them. A photo an engineer takes is marked Engineer Picture in the image.
Who confirms the injection worked?
The engineer does, and the record shows it. When a crew marks a defect done, it is awaiting validation, not closed. The engineer sees the before and after photos side by side, the packer counts, the litres of product, every work session and the defect's history on one screen, then validates or sends it back. Sending back needs a comment, for example asking for another round of injection below a packer that is still damp, and that comment goes to the top of the defect for the crew underground. When the defect comes back done it returns to the queue. A validated defect carries the engineer's name and time, and shows whether it passed first time or after rework, so the record says how the repair was accepted as well as that it was.
What about injection pressure?
The tunnel register records counts, product, litres, sessions and photos. It does not log pump pressure on tunnel defects. The cavern workflow built for joint and hose injection does record pressure at the end of each pass; it is described in the cavern joint injection case study.
See it on a live job
On Sydney Metro West Portion 1, packers, product and photos are logged as the work happens rather than reconstructed afterwards. The Portion 1 case study has the figures, and the tunnel defect register page covers the register the injection records sit in. To try it with your own crews, start a 14-day pilot.