Hi Michael,

Assuming you are already an inspector, the first order of business would be to verify your certifications currently held to determine if we have a need for someone with your qualifications.  Secondly, membership in IUOE Local 12 is mandatory, so we would need to know if you are currently in Local 12, or would be willing to join Local 12.  Assuming you are a member or are willing to join, we would then speak with our Dispatch who would provide you with contact information for Local 12 so that you can get on the out of work list which would allow us the opportunity to request an inspector with the qualifications that we need.

Hope this helps, and thank you for asking!

Hi Mario,

Yes, if you are referring to asphalt binder chemical extraction, we use Trichloroethylene. Twining is capable of running chemical asphalt binder extractions following ASTIM D 2172, Method A and B.

We are not aware of any Standard test method utilizing thermal imaging cameras to confirm grout and reinforcing steel installation in a CMU wall.  However, Ground Penetrating Radar (GPR), is a non-destructive method that can be used to verify that cells are grouted and also to verify placement of reinforcing steel.

Hi Rabindra,

Please submit your resume on our website and someone will be in contact with you.

Hi Ed,

To better respond to to your question, I would need more information, and to review the Mix Design and Aggregate properties.  This could be a very a project specific answer. By reviewing these, I may be able to come up with a more complete answer. However, here is a list of parameters that can affect the Dry Strength of your mix:

• Aggregate Gradation: mixes with finer aggregates (higher passing sieve #4) show lower strength
• Asphalt Binder Content: higher asphalt content lowers the strength
• Coarse Aggregate Crushed Particles: more crushed surface aggregates will increase the strength
• Fine Aggregate Crushed Particles: more crushed surface aggregates will increase the strength
• Use of Natural Sand: usually use of natural sand will reduce the dry strength.

Please note that many other parameters are involved in determining the properties of each mix, and above mentioned factors may not necessarily change the mix properties as expected. Some try and error would be required to come of with the correct resolution. Please feel free to contact me to discuss this matter further.

Best,
Amir Ghavibazoon, PhD
Pavement Engineer
aghavibazoo@twininginc.com 

We would like to discuss this in more detail with you in order to provide a helpful response.

Please contact Esmeralda Martinez at 562.272.7231 ext 144 or emartinez@radcoinc.com.

As with almost all questions related to materials testing and inspection, the answer to this question will depend on the authority having jurisdiction over the project.  Per 1704.2.5 of the 2013 California Building Code (CBC) special inspection of structural load-bearing members and assemblies at the fabricator is required.  However, per the exception in 1704.2.5.1 if the fabricator is approved by the building official this requirement is waived.  Each jurisdiction has their own procedure/policy for approval of fabricators so you should verify with the jurisdiction and with your contractor if the fabricators that will be utilized for your project are approved.  In addition, should complete joint penetration welds be performed at the fabricator these will still need to be independently ultrasonically tested as the exception is only for inspection and does not also apply to any testing required.  Please also note that this exception is not present in Chapter 17A which governs DSA and OSHPD projects.

Gravel and geosynthetic products are very expensive and large amounts are often needed to stabilize particularly soft soil.  Additionally, overexcavation and export of these soft and usually wet soil needs to be performed and this material generally needs to be disposed as it is not usually fill material.  In many cases, cement-treating the soft soils is a more practical and economic approach to stabilization.  If the area is relatively large, cement-treatment of the upper approximately 10 to 15 inches of soil will likely be less costly than overexcavating and placing geosynthetic products and layers of gravel.  This approach has been adopted frequently for troublesome roadway subgrades.  In addition to stabilizing the roadway subgrade, the cement treatment also provides structural support characteristics that can be calculated and accommodated in the design.  There a few specialty contractors that perform cement treatment and they are usually willing to provide free estimates so that you can judge whether your site is appropriate for this approach.

Cold In-Place Recycling (CIR) can be simply applied to neighborhoods as long as the CIR train can move around and can exit the project location. In this manner, the only locations that have proved difficult for CIR trains are cul-de-sacs and driveways. Also, CIR train cannot cover the top of the “T” intersections on the roadways, unless small cold planer are be utilized

To best answer this question, we would need to know the intended application of the base material.  Assuming that it will be used for a base course material below a Portland cement concrete pavement (hence the concern for sulfate), table 19.3.1.1 of  ACI 318 prescribes the necessary water-cement ratio and compressive strength to mitigate the potential for damage of the concrete due to the presence of sulfates.

I would welcome the opportunity to discuss this with you further and provide you with a more tailored answer to your specific situation. I have provided my contact information below, and look forward to hearing from you.

Paul Soltis
Vice President, Geotechnical Engineering
PSoltis@twininginc.com
562.426.3355 (office)