Use of Polymeric Strip for the construction of Reinforced Soil Wall



Reinforced Soil wall with concrete facing panels and geogrid as reinforcement are well-known systems used in India and abroad for the construction of retaining walls, abutments, and wing walls. The polymeric strip was introduced as a replacement for the metallic strip reinforcement in the early 1960s, which represented evolution and a significant advantage for both cost-effectiveness and performance over the metallic strip.

Polymeric strip-reinforced Soil walls are recommended in the construction of RSW in case of poor subsoil conditions, chemically aggressive environment, or in warm climates, where steel could represent an issue. The general behavior of the reinforced soil wall structure depends on the interaction between the soil reinforcing elements and the surrounding soil, which is linked to the properties of the materials used and the construction methods adopted. As an alternative to traditional systems, high adherence polymeric soil reinforcing strips have been introduced in order to increase the design life of the wall even in highly aggressive environments, reduce the overall project costs and provide design flexibility. 

RSW with polymeric strips are popular structures all over the world but relatively recently getting popular in India. We would like to share a similar case study as follows 

REINFORCED SOIL WALL FOR BRIDGE APPROACH AND RECONSTRUCTION OF ROB 39A AT GONDAL RAILWAY PORTION, GUJARAT

Products used: TECHSTRAP POLYMERIC STRIP
Quantity supplied: 72473 M
Year of construction: NOV 2019 - OCT 2020

Problem: Project scope included reconstruction of ROB in the prime area of Gondal. Old ROB was aligned in skew and there was no other alignment possible for approaches due to city congestion. For ROB, the maximum wall height was approximately 11m and for such height, RCC walls would not only be costlier but also difficult to construct. Due to various reasons such as the limited right of the roadway; to minimize the land acquisition, poor founding soil conditions, aesthetics, economic considerations & ease of construction, etc., the Consultant suggested constructing Reinforced Soil Walls (RSW) for the approach of ROB

Solution: After going through the soil investigation report and site visit, the consultant proposed construction RSW with polymeric strip as this system can reduce project cost and environmental impact compared with traditional methods.
RS walls with Polymeric Strip have many advantages compared with conventional solutions. Some of these are:



Simple and rapid construction procedures and do not require large equipment 
Need less space in front of the structure for construction operations 
Has flexibility and capability to absorb deformation due to poor subsoil conditions in the foundations. ·
 Deep foundations are not required. 
Cost-effective and aesthetically pleasing. 

What is TechStrap Polymeric Strip? 
TechStrap Polymeric Strips are geosynthetic strips (polymeric strips/straps with a flat webbing like structure) specifically engineered for the reinforcement of soils and other fills for the construction of reinforced soil or mechanically stabilized earth structures. TechStrap Polymeric strips comprise a core of closely packed and tensioned high tenacity polyester filament yarn tendons encased in a tough and flexible sheath of linear low-density polyethylene. The Polyester filament yarns used in Strips are of high tenacity, high molecular weight, and low carboxyl end groups, ensure high tensile strength and stiffness, low creep, and excellent durability. The LLDPE sheath on the strip provides a tough, flexible, and textured covering to the polyester tendons imparting dimensional stability, protection to the tendons from weathering and mechanical damage, and developing excellent frictional interaction with fill. The Polymeric strip with high long-term design strength and stiffness and excellent bond strength is ideal for the reinforcement of soils and other fills for the construction of reinforced soil structures.

The proposed standard cross-section drawing for variable height is as given below:

Based on the height of RSW, the strength of the Polymeric strip and length of reinforcement of the polymeric strip may vary. The project was successfully completed in October 2020.




                    Erection of RCC Panel in progress           Installation of Techstrap polymeric strip in progress 


                                                  Completed RSW with TechStrap Polymeric Strip

About Techstrap polymeric Strip 


TechStrap Polymeric Strips are manufactured from high-quality materials using state-of-the-art machinery. The manufacturing facility is ISO 9001:2015 certified and the product range is CE certified.

Our in-house laboratories have the latest equipment and accessories for testing the polymeric strips in accordance with ASTM and ISO standards. We have a stringent quality control program for testing both incoming materials and finished products on a regular basis. 

TechStrap Polymeric Strips have undergone a comprehensive series of third-party performance testing at TRI/Environmental Inc., USA, BTTG, U.K., BICS U.K, world-renowned independent accredited laboratories. 

The performance of TechStrap Polymeric Strips has been demonstrated through the successful completion of a large number of reinforced soil structures in India. The end-users of TechStrap Polymeric Strips include the National Highways Authority of India, State PWD's, Municipal Corporations, and Northern Railways, etc.

Please Contact for further details :

Namrata Bichewar (Design Engineer) 

Manish Barot 
Head of Technical Sales and Business
Development, 

TechFab (India) Industries Ltd.
phone  : 91- 22-2287 6224 / 6225
e-mail : info@techfabindia.com
website: - www.techfabindia.com

 

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