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GENERAL PUBLIC and CONSTRUCTION INDUSTRY PILING and GROUTING ENGINEERING SAFETY NOTICE
The current Construction Industry economic climate is highlighting serious flaws in Western Australia’s Building Regulations and relevant Licensing Legislation.
Western Australia: The only State where there is no legal or professional requirement for individuals or organizations to be licensed, qualified or experienced to conduct piling or ground stabilisation design or construction works. Even though this work supports buildings, structures and deep ground excavations. Sound ridiculous? Anyone can start this type of business tomorrow, call themselves qualified to do the work, fail to provide any engineering certification for what was done and nobody can stop them. Most people are unaware of this fact stating, “How is This Possible?” Don’t believe it? A quick search of the following government website clearly shows no requirement for a contractor or supervisor to be either experienced, qualified or licensed to conduct piling or grouting works in WA.
See: http://www.licencerecognition.gov.au/Pages/LicenceSearch.aspx
Historically the WA piling and soil stabilization sector held the reputation of producing safe quality project successes. This held merit with reputable builders and construction companies and in itself was a form of managing what was considered acceptable. Sadly, in today’s economic climate, that era seems to be at an end. Segments of the building industry now seems focus on price at any cost, deliberately turning a blind eye to poor or even no engineering design, chequered works performance history, the use of unproven/unknown materials, untrained/unqualified installers and no site specific engineering certification, resulting in poor “Fit for Purpose“ outcomes.
The lack of formal project specific engineering design and certification is big concern in WA. Again anyone can pass themselves off as an engineer and “certify” a design, but such a certification is effectively worthless and fraudulent. For Engineering Certification to be effective it must be backed up with Professional Indemnity Insurance. Such insurance only indemnifies a CPEng registered with Engineers Australia who does not do anything negligent. Certified Engineering Certificates must cover two elements:
A certifying “Engineers Certificate” (letter) is the “design performance guarantee”. Issued confirming both design and installation conforms to the relevant Australian Standards, Building Codes and that the installation has been carried out in accordance with the design’s intent, i.e. Fit for Purpose. Both are required to comply with principal contractor’s builder’s building license, public liability and insurance and the design engineer’s professional indemnity insurance. Without purpose issued engineering design and installation certificates an insurance company will not indemnify the insured exposing all to significant financial risk and where death of injury occur due to failure criminal proceedings for negligence are likely applicable. The seriousness of this issue cannot be overstated as any comeback will be borne by the sub-contractor himself exposing all parties to potential financial shortfalls and lack of accountability. Insurances provides industry and the general public peace of mind and helps keep the industry accountable.
The lack of formal design & certification is of grave concern to Engineers Australia (“EA”). We understand EA has undertaken an investigation into this lack of engineering certification on projects and are about to release their recommendations to the relevant Authorities. As members of EA and as certifying design engineers we welcome this news as some in the construction industry have conveniently forgotten that this requirement does impact price.
It’s a fact that some new industry sub-contractors don’t have the ability or capability to provide engineers certification for their works. This is evidenced by the circulation and reliance of non-site, or project specific, “generic” engineers drawings provided by the sub-contractor and passed off as “certification”. This is nothing more than a fraudulent attempt to pass a document off as something it is not. One can only imagine a builder presenting one of these in a Court of Law defending a matter involving structural damage, injury or loss of life. We frequently witness the use of a well know engineering firms generic detail showing an unspecified grout block under a boundary screen wall. The drawing detail was relied upon by the grouting sub-contractor for use on an existing 2.0m high boundary retaining wall that was to have a deep adjoining excavation. How do we know? We were asked to price the same design but we refused.
Another instance occurred when our engineers designed a grout block for a retaining wall @3.8m below ground level. The builder obtained a price from a relatively new contractor who specified @3.2m depth. Site visits and a survey check with the builder quickly established that 3.2m was insufficient and would have resulted in catastrophic structural failure. Luckily this was avoided in this instance. The building industry by ignoring (deliberate or otherwise) these issues will have massive ramifications for the industry if not urgently curtailed. The industry is left exposed to potential catastrophic structural failures and loss of life.
Piling and soil stabilization are specialist works and should only be carried out by reputable recognized experts in the field having years of on-site training and expertise.
Since Foundation Engineering Group developed our technologies some 20 years ago the construction industry has undergone a transformation such that it allows self-inspection and certification outside the remit of local authorities. As a result part of the construction industry itself has driven down the importance of site inspections and certification by engineers to a point where a section of the industry is using these generic engineering drawings and not site-specific engineering design & certification for their projects. This behaviour is undertaken by some of the piling and or grouting sub-contractors without the builders knowledge, though the builders should be aware from the difference in quoted prices they receive that something is not quite right.
Those who have been in the construction industry for some time will recall seeing design engineers notes attached to drawings showing piling or grout injection. Those notes were intended to guide the builder to use recognized specialist contractors to ensure industry standards were maintained. They looked something like this:
Example 1 (Part A)
Specialist Contractor
“Piling/grouting to be designed and certified by the specialist contractors design engineer. Engineering certification is to include the piling/grouting design and installation outcomes. Design and certification is to be provided to this office for review and approval a minimum of 7 days before commencement of the works.”
The following is a list of recognized specialist contractors:
Example 1 (Part B)
Materials – Piling (Part a)
“All materials are to be in accordance with the relevant Australian Standards. No second hand material’s are to be used. Steel mill certificates are to be provided where appropriate. NDT is to be carried out as per specifications. Pile testing as per specifications. Pile testing to be submitted for approval prior to finalizing works”
Materials – Microfine Grout Injection (Part b)
“ The proposed grout material specifications are to be submitted to this office for approval prior to the commencement of works. Only microfine cement grout with the following minimum specifications to be used:
There are typically two main applications for microfine grout injection:
1. Soil Stabilisation, such as for stabilising/upgrading an existing structure foundation (underpinning).
2. Soil Retention, where immediate or adjoining area excavation is required to build an additional structure.
Some sub-contractors are working to grout depths and/or cubic volumes and/or water to cement ratios that are insufficient to support the actual loads.
In application 1, it is almost impossible to determine that the works have been carried out correctly without exploratory drill or probe testing, other than to wait and see if further settlement occurs. Unless full flow & time monitoring and further exploratory testing is carried out some sub-contractors find it’s easy to “cheat”. Substandard performance is unlikely to be detected any time soon after works. Catastrophic structural failure is unlikely as is the threat of serious personal injury or loss of life. Accurate monitoring and recording of the installation process is thereby a critical component as it confirms correct injection volumes and placement of grout has occurred. The same checks cannot be used for the following application as the load requirements and final construction outcomes are vastly different and require a somewhat different approach.
As with application 1, application 2 may or may not have an existing structure applying a surcharge load on the ground at a specific Mpa. There is likely to be additional horizontal and overturning forces that will come into play when excavation occurs on either side of the grouted soil. These combined forces create a potentially dangerous environment where inadequate engineering, installation methods, or inferior products are used and potential for structural failure is imminent.
Catastrophic failure can result in complete building loss and loss of life. Collapse can occur with virtually no warning, it just happens and it’s terrifying. The scenario of an existing structure atop of grouted excavation and that structure has people inside and or construction workers are at base of excavation, constructing new foundations and catastrophic and failure occurs, serious injury or fatality may be significant. If you have stood alongside a deep excavation grout wall and looked up at a large structure standing on top then you will automatically appreciate the magnitude of concern.
Most people are stunned to learn that whilst there is an Australian Standard for Piling, AS2159-2009, there is no Australian Standard for Microfine Grout Soil Injection. And therein lies another problem. An Australian Standard is intended to set the benchmark for works to be carried out. To hold individuals accountable for what they do. No Standard invites unscrupulous contractors to cut corners, reducing both safety and quality.
Another way to ensure compliance with Industry and Australian Standards is to ensure the nominated business is certified to ISO9001 that will ensure that QA controls systems and processes are in place making individuals and the company accountable for all they do.
It appears that some structural engineers and construction industry businesses have dropped the ball when it comes to ensuring works are done in accordance with Australian Standards using specialised products and to what the industry considers Industry Acceptable Practice. West Australia’s Piling and Ground Stabilisation Industry must also shoulder some responsibility as up until this point we have not been proactive in exposing bad practices and products to the engineering and construction industry through fear of being labelled a sulking competitor. That is no longer the case.
We’ve had recent dialogue with industry competitors that we consider reputed and confirm the industry is united, having a similar opinion. And all are now determined to help the construction industry and relevant Regulatory Authorities eradicate these life threatening and compromising practices. If you are not already aware of the problems within the industry I encourage you to contact any of your preferred established/reputed company and discuss the matter. I have had dialogue with them all and can confirm my concerns are those of our industry at large.
We are hopeful the relevant Authorities, Industry Associations and the construction industry itself become pro-active in assessing and implementing new policy and safe work practices.
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