The basic principal is that each part of the physical works (and/or each process) is included in one of a number of Lots which are recorded on a Lot Register. All of the testing, inspection, conformance checks and valuation of work completed is referenced back to the Lot which contains the work in question. The records associated with each Lot are compiled and managed as a separable record of completed work.
Why Lot-based Quality Assurance
Lot based quality assurance is structured and flexible. It can be as simple or comprehensive as is appropriate for your project. At its very basic level, you can maintain a list of the sections of your project and use this list to collate records like Tests and Non-Conformances. For more complex project it can be used to record the quantity of work associated with a Lot, generate Progress Claims, track Variations, manage Checklists and ITPs and calculate appropriate numbers of Tests.
Of course, sometimes you have no choice but to adopt Lot based QA due to external factors such as your contracts or legislative requirements. In this situation you need an effective method of complying with your obligations.
What is a Lot
The first step to understanding how Lot based quality assurance (LQA) works is understanding the concept of a Lot.
A Lot is simply a specific, discrete section of the physical work or a process which forms part of the works being constructed. For a small, simple project you may simply break Lots as following:
- Management Plan Approvals
Generally, on larger projects many Lots would make up each of these categories. This may be because a section of work is too big to easily be managed in its entirety, works of a similar type occur at different times or locations, or because of other restrictions imposed on Lot definition by the project specification.
An example of this may be the pavements where a Lot is restricted to a single day's production with a paving machine, of a single type of gravel. Something similar to this is found in the TMR specification for pavements MRTS08:
Where no maximum Lot size is specified for construction is specified in Clause 1.2 of Annexure MRTS08.1, the maximum Lot size shall be equal to the area (in m2) of production of one completed stabilized layer achieved during one work period, provided the material is essentially uniform.
In this case the Lots may be as follows
- Lot #ABCDEF001 – Subbase Ch 10,000 to 11,500 – day 1
- Lot #ABCDEF002 – Subbase Ch 11,500 to 12,750 – day 2
- Lot #ABCDEF003 – Base Ch 10,000 to 11,500 – day 3
- Lot #ABCDEF004 – Base Ch 11,500 to 12,750 – day 4
When Do I Define a Lot?
While lots can be defined before a project commences, this is not recommended as it is impossible to know what will happen during the project that may influence how a lot’s extents may change. It is best practice to create lots immediately prior to commencement of a section of work. If in doubt, check your contract as contracts are quite often very specific about the timing and definition of Lots for particular Work Types.
CivilPro maintains your Lot in the Lot Register, the central reference point for all of the individual elements of work that comprise your project.
Inspection and Recording Results
Each type of Lot (i.e. a pavement, excavation, concrete pour etc.) has particular characteristics which are inspected and tested to ensure that the work complies with the requirements of the contract. Generally, the required standard of work is defined by the Contract Specification or legislated standards. It is also common for contracts to define the elements of the works which must be inspected and tested, and how often this occurs.
Rather than trawl through the contract every time work is undertaken to determine the compliance requirements, an Inspection and Test Plan (ITP) can be authored. This communicates very clearly to the project team and also clients, what will be tested, how and when for each type of work.
This ITP may be simplified further, or reproduced in its entirety as a Checklist which is printed off in hard copy for use as a record that individual items have been inspected on lots containing this type of work.
CivilPro has an ITP creation and management tool which also produces Checklists and determines the appropriate testing for individual Lot Types.
Testing and Recording Results
Tests are often required to verify that elements of work have been completed to a certain standard – such as compaction tests or concrete strength tests. These tests can occur prior to, during or after execution of the works. Testing requirements are generally specified in the contract documents.
It is usual that such tests are taken by a third party to ensure integrity of the results. To record the tests that have been requested and taken, a system of Test Requests and a method for recording Test Results is required.
CivilPro maintains a Test Request Register which provides the capability to record results and generate testing locations randomly. Test Requests are linked back to the relevant Lot.
No matter how good a project team is, sometimes things go wrong, whether it be unexpected rain damaging the presentation of your concrete, a supplier providing substandard product or a process that isn't executed correctly. In these instances, the only thing worse is when it happens again.
Identifying and managing non-conforming processes and products is an essential, and generally contractually required element of a project. The process involves identifying problems, determining an appropriate course of action, getting that action approved and checking to see the actions are implemented.
CivilPro provides a mechanism for recording your non conformances, cross referencing them against Lots, tracking the approval process and ensuring follow through.
Quantities and Payment
Every project has a Payment Schedule. The extent to which contractors are entitled to progress payment for work completed is determined through the percentage of each item in the schedule that has been finished.
It is also not unusual that payment be dependent upon the work meeting certain standards. In order to make claims it is therefore useful to be able to identify the information demonstrating compliance (your Lot records) and associate them with specific element of your construction payment schedule. As each Lot is either complying or not, the contractor can sum the Quantities across complying Lots and use this as the basis for payment.
CivilPro manages the relationships between work completed, payment and compliance. Lots are statused as Conforming, Guaranteed or Work in Progress. Each status can be included in payment claims or not as is appropriate for your project. If you don't need to use Lot assigned Quantities, CivilPro still manages your Progress Claim submissions independent of your Lot records.
Most projects are subject to change during their life cycle. If this change incurs an increase or decrease in costs/payments, then this needs to be tracked.
CivilPro manages variations, their association with quality assurance records and their impact on the Progress Claim process through the Variation module.