Frequently Asked Questions

How durable are Tensar geogrids?

The durability of any geogrid is dependent on two main factors; the polymer composition and the environment in which it is placed. Tensar uses high quality virgin polypropylene and HDPE in the manufacture of all geogrids which are recognised as effectively inert to all common in soil degrading mechanisms. Tensar geogrids are manufactured under a strict Quality Control regime and are required to satisfy the durability requirements in independent approval documentation and audited manufacturing procedures.

Please contact Tensar for additional information.

What is the size and weight of a Tensar roll?

Tensar manufactures a wide range of products which are provided in a range of standard roll sizes. The size and weight of these rolls is governed by the grade and type of material.

Can we substitute different types of Tensar products in a project?

The range of Tensar products have been designed for a variety of applications. We will always specify the most appropriate material for your application, having regard to the most economic and serviceable grid layout.  If there are special circumstances, alternative grid layouts using different Tensar grids may be possible. Please contact Tensar before making any substitution.

Why should I use Tensar products when I can find a cheaper alternative?

Clearly, not all products are of the same quality.  Tensar produces independently tested, high quality products, with a long track record of proven performance, based upon extensive research and development. Tensar offers a range of services to support the use of our products and systems in your application.  Designs using Tensar products and systems are based upon the unique characteristics of those products and systems and the use of alternatives should be accompanied by a design suitable for those products and systems.

Can your new TriAx grids save me more money?

TriAx geogrids have been proven through laboratory, full scale testing and global site experience to give cost saving benefits over traditional and other geosynthetic solutions. Tensar can advice on the precise TriAx product and/or system for your site conditions.  For further information please contact Tensar or visit the website, www.tensar-international.com

Do you offer Tensar erosion control products?

Tensar offers a range of erosion control products. The Tensar Group of companies includes an erosion control specialty manufacturer, North American Green (NAG), which manufactures rolled erosion control products.  For further information please contact your local Tensar Representative and your query will be passed through to NAG.

What are the benefits of Tensar product?

Tensar products and systems are designed to optimize, stabilize and/or preserve civil works structures. In general Tensar grids are used in many applications to enhance soil behaviour by providing safe and cost-effective reinforced and stabilised soil structures.  Information is available via the website, www.tensar-international.com , or by contacting your local Tensar Representative.

Where can we find information on Tensar products, systems and services?

Literature is available on the website at www.tensar-international.com, or by contacting your local Tensar Representative.

Can we save costs and still maintain an attractive appearance for our structure?

Yes.  There are many different facings available in Tensar’s Grade Separation Systems and Services which deliver a range of aesthetics. Tensar grade separation systems are designed to deliver savings in cost and time over other methods of construction.  Please contact your local Tensar Representative for specific projects or visit the Tensar website at www.tensar-international.com for general information.

What are the limits and parameters for Tensar reinforced soil in terms of size, angle and finish?

There is a wide scope for Tensar grid reinforced soil structures.  Near vertical single structures over 20m high and much higher stepped structures have been designed and constructed.  However specific design limits can only be determined once the specific conditions of the project and requirements for the application are known.  Please contact your local Tensar representative at an early stage of your project to determine whether Tensar products and systems can be used. We can assist in developing a concept or designing it for construction based on your project needs.

Can I have a price for your Tensar geogrid please?

Our prices vary depending on the nature of your project and the Tensar products and systems to be used.  Please contact Tensar Customer Services for information on product costs

Can you provide a budget estimate for Tensar products and systems?

Budget costs depend on the nature and type of application required for your project.  Tensar offers a free Application Suggestion/Conceptual Design to provide a preliminary cost estimate for Tensar products and systems. This information can be used for preliminary estimation of costs in your project. Please contact your local Tensar Representative for further information.

What is the normal time for receiving Tensar conceptual or detailed designs for grade separation systems?

Tensar will provide a free Conceptual Design, typically within 5 working days of receipt of required information.  Proposals for Design & Supply projects can typically be provided within 7 – 10 working days of receiving required information.  Design and drawings for a Design and Supply contract will normally be completed within 2 – 4 weeks of contract execution and the required design information.  Please inform your local Tensar Representative of specific time constraints and we will endeavour to accommodate your requirements.

What is the normal time for receiving Tensar Application Suggestions or Designs.

Tensar will provide a free Application Suggestion, which is a not for construction application concept, within 7 days of receipt of the required information from you.  Tender submissions for Design & Supply projects can be provided within 7 – 10 days of receiving the required information.  Design and drawings for a Design & Supply contract will normally be completed within 2 – 4 weeks of receipt of order and the required design brief.

We received a Tensar design and supply proposal/quotation some time ago and would like to place an order in the near future. What do I need to do?

The main concern is to ensure that there are no changes to the project which might impact our original design.  We would require current project information in the form of an updated plans and specifications. After reviewing this information we would either confirm that the original design is still applicable or provide a revised design.  We will notify you of any cost implications associated with redesign or price increases associated with time lag and requote if necessary.  Please contact your local Tensar Representative to discuss the project and notify any changes that may have been made to the original design brief.

Can someone come on site to show us how to install the Tensar products and systems?

Yes.  A site visit at the start of construction is offered as part of Tensar’s standard Design & Supply service, but can be extended to other projects in which Tensar products and systems are used.  The purpose of this visit is to describe and demonstrate the techniques required to correctly install Tensar products in your project.  We strongly recommend that all contracting personnel involved in installation are present for our construction sequence demonstration including the system designer and QA/QC personnel. Please contact your local Tensar Representative to arrange a site visit.  Construction Sequences for the various Tensar structures are also available on the website at www.tensar-international.com

Are there any installation guidelines for Tensar products and systems

Tensar provides a range of practical information and guidance for the safe handling, storage and installation of Tensar products and systems. These are called installation guides.  Please visit the Tensar website www.tensar-international.com, and download the relevant installation guide. Alternatively please contact your Local Tensar Representative and they will send the appropriate sequence.

Should Tensar geogrid be pre-tensioned during construction of the wall?

The ‘slack’ should be taken out of the grid as presented in system specific installation guidelines.  Please visit the Tensar website at www.tensar-international.com to download the information.

Can you provide a design certificate?

In some countries a Design Certificate is required, particularly in infrastructure projects.  In these instances Tensar can sign the certificate. Please contact your local Tensar Representative.

Do you overlap the grid?

Yes, but only typically in stabilization applications.  The amount of overlap depends on the conditions but is generally between 300mm and 900mm.

Can you provide a sealed detail design drawing?

In some countries, particularly North America, regulations require a sealed design from a licensed professional engineer. Tensar is licensed in a number of jurisdictions. Please contact your local Tensar Representative.

If there was a road accident or fire and the face is damaged, is that OK?

Normally this causes face damage only and a remediation program may be required to repair the damage.  Structurally the primary geogrids in the mechanically stabilized earth mass are carrying the loads. Please contact your local Tensar Representative to discuss the situation

How do I repair my damaged geogrid?

Repair techniques vary considerably depending on the nature of the application and damaged caused.  For further details on the maintenance and repairs to damaged of Tensar modular block faced retaining walls, refer to IB/TW maintain. Please contact your local Tensar Representative to discuss the nature of the damage.

Do you provide construction phase services?

Yes.  Tensar provides support for sales of our products and systems.  Tensar representatives can provide information and advice before the start of construction on installation techniques and will be available for consultation regarding practical issues impacting on installation and performance of Tensar products and systems during construction.

Can you issue an as built drawing?

This is possible, but as Tensar is not involved in supervision and inspection of construction works we cannot verify that construction complies with our detailed design. We can however provide a final set of drawings incorporating change orders or revisions, or revise the status of the contract drawings to “as-built” on the written and signed assurance of the contractor that the construction has been carried out accurately and correctly.

Can you certify that we have built the wall in accordance with your design drawings?

No. Tensar does not offer construction supervision services, is not present during the whole construction process and will normally visit the site infrequently, or at your request. We are therefore not in a position to say whether or not the construction is in accordance with our design.

Do you maintain professional indemnity (PI)/ errors and omissions (E&O) insurance?

Yes.  We consider PI/ E&O insurance to be an important part of our business management approach and an appropriate financial protection for Tensar and our customers in the unlikely event of an error or omission.  PI/ E&O is purchased annually and responds to claims made during the period of the policy.  We are committed to maintaining our PI/ E&O insurance with reputable international insurers.

What is the difference between an Application Suggestion/Conceptual Design and detailed design?

An Application Suggestion/Conceptual Design is a preliminary concept whose purpose is to demonstrate whether and how a Tensar product or system could be used to satisfy the project need.  It is generally based on incomplete or assumed information and is therefore not intended for construction.  Tensar can undertake a detailed design involving Tensar products and systems. A detailed design provided by Tensar is intended for construction and is based upon clearly defined information provided by you or your consulting engineer, which is contained in a design report/Design Brief.  In the US the detailed design will be sealed by a professional engineer.

Can Tensar design a sound barrier?

Yes.  We are sometimes asked to design to a geometric configuration which has been acoustically designed by others. Tensar would require this information, including key plan/section drawings and Site Investigation information. Please contact your local Tensar Representative to discuss the necessary data, soil parameters and other information requirements.

Can we further optimize the Tensar wall design you have provided?

Possibly as this depends on a number of factors.  See 4.4.  The wall design is based on information provided by you to Tensar as summarized in the design report/Design Brief.  The design has been developed by the Tensar design team as the most efficient and cost effective design applying design parameters contained in the design report incorporating Tensar products and systems. Contact your local Tensar Representative to discuss options for optimization considering cost, constructability and other factors.

Can we change the soil parameters?

Yes. Tensar is not responsible for establishing soil parameters and relies on information provided by you or your consulting engineer. This information is contained in the design report which sets out the advice you or your consulting engineer have provided. The design report/Design Brief forms the basis for Tensar design of a structure incorporating our products and systems. If the soil parameters on which the design is based have changed a new design report, incorporating these changes, is required and a new Tensar design will be provided to you.  This may involve additional costs for substantial changes.

Will the design be further optimized by changing the soil parameters?

It may be possible to further optimize the Tensar design by providing improved soil parameters to our design team or by use of higher quality fill material.  Prior to providing Tensar with changed soil parameters, we strongly recommend that you validate these by testing or review and confirmation from your geotechnical engineer This may involve additional costs for substantial changes.

Can Tensar confirm Tensar material properties and factors used in design?

Tensar can provide our Quality Assurance, Quality Control testing of material to demonstrate that it complies with our detailed design. All material properties used in design are subject to local regulatory requirements.  The values provided depend on the particular application and design method.  Please contact your local Tensar Representative for further information or visit the Tensar website:  www.tensar-international.com

Can Tensar design a traffic barrier?

In North America Tensar is sometimes required to design traffic barriers as part of design and supply contracts for Tensar grade separation systems. However, in most other countries traffic barrier design is not part of Tensar detailed design and should be designed by an independent engineer.  Contact your local Tensar Representative for further information.

How can we demonstrate the economic benefit of the Tensar products and systems?

Comparisons of the total costs of alternative approaches will demonstrate economic benefits.  Please contact your local Tensar Representative to discuss how this might be done.

Can you design a working platform for safe access of heavy plant?

Yes.   We can usually design a working platform using Tensar products and systems. We require you to provide information for our design report including the soil parameters and the loading cases.  Please contact your local Tensar Representative to discuss the project further.

Can you design a retaining wall?

Yes.  Tensar has developed a number of grade separation systems for reinforced soil walls with different facings.  Please contact your local Tensar Representative to discuss the possibilities or visit the Tensar website at:  www.tensar-international.com

Can you design a vegetated reinforced soil slope?

Yes.   Tensar has developed a number of grade separation systems for reinforced soil steep slopes with different facings.  Please contact your local Tensar Representative to discuss the possibilities or visit the Tensar website at:  www.tensar-international.com

What options can Tensar provide to stabilize roadways over poor soil?

Tensar has worked successfully in the construction of roads over low strength soils for many years.  The inclusion of Tensar stabilization grids in the granular layers of pavements can enable efficient construction in very difficult ground conditions.  For examples of this application please visit the Tensar website www.tensar-international.com.  For further information and discussion please contact your local Tensar Representative.

What is the benefit of using Tensar geogrid in road sub base?

The inclusion of Tensar stabilization grids in the granular layers of a road construction can either reduce the amount of granular material required by up to 40% or extend the life of the pavement significantly.  Please contact your local Tensar Representative to discuss specific projects

Can you review my project and propose Tensar products and systems for use?

Yes. Early involvement with your design team will enable us to explore potential cost and time saving opportunities in your project  Please contact your local Tensar Representative to arrange a visit to discuss specific projects.

Can I reduce stone thickness in roadways by use of Tensar geogrids?

Yes. Typically our Application Suggestion/Conceptual Design can illustrate savings from reduced use of materials such as stone, asphalt or other pavement materials.  The design needs to be based on project specific parameters and expected performance levels

What information do I need to provide you with so that you can help me compare the difference of a Tensartech wall and a reinforced concrete wall?

Each project is different. Typical information required includes soil characteristics, wall geometry, specific loading conditions and location. Please contact your local Tensar Representative to discuss the actual project and the information required to produce a Conceptual Design

Can I use a geo textile in place of a geogrid?

No, not if the design is based on the use of a geogrid.

We have sourced some granular fill on the site for the retaining wall. Is it OK to use it?

The geotechnical properties of the fill material used in reinforced soil structures are critical in the design, cannot be verified by visual inspection and should be determined from testing for complete accuracy.  The properties of fill products can be highly variable dependent on source.  Geotechnical engineers familiar with the fill materials in question and their variability may be able to provide approximate parameters or advice on a suitable testing program.

We are having some problems with the construction. Can somebody come and give us some advice?

Yes, a Tensar representative can visit the site to provide information and advice relating to the correct installation of Tensar product and systems, if necessary.  Obviously we would first need to clarify the nature of your construction problems.   This does not extend to inspection and certification or to any form of supervision. Please contact your local Tensar Representative to discuss your problem.

Do you supervise installation?

No.  Tensar does not offer supervision services, and does not undertake to direct or control the workforce and use of construction equipment during construction of any works involving Tensar products and systems.

Is it possible to have foundation or other structural elements within the stabilized earth mass?

This is possible provided that the wall can be designed to accommodate the foundation element types and locations relative to the facing elements. This should be considered as early as possible within the overall design. The construction sequence, methods of installation and the effects on the wall facing should also be carefully considered. If you have engaged Tensar to carry out design, you should provide Tensar’s design team with information regarding the proposed foundation design and construction sequence and installation method.

We have decided that we want to build the wall 3m higher. Can we just use the same grid layout?

No. In all structures the design is specific to the actual dimensions and soil parameters provided and therefore any changes in geometry require a new design assessment.  Please contact your Tensar design team with your revised design requirements..

Can I leave the geogrid exposed to sunlight or will it degrade due to UV exposure?

This depends on the time period involved and the geographical location of the project.  All Tensar geogrid has UV degradation inhibitors and can typically remain exposed for short periods of time during construction, But all polymers degrade with extended exposure to UV and Tensar offers alternative products specifically designed to resist long term degradation from UV, heat and moisture..  Please contact your local Tensar Representative for further information about your project.

Will you visit site on a regular basis to inspect progress of our works?

No. Tensar does not offer supervision nor inspection services.  A Tensar representative will provide installation advice at the start of the work and can visit the site, upon your request, to comment on practical aspects of installing Tensar products or systems during construction.