Construction of Flyover At NanaVarchha on Varchha Road in Surat.Owner:
Surat Municipal CorporationContractor:
Rajkamal Infrastructures Pvt. Ltd.Consultant :
S N Bhobhe & Associates Pvt. Ltd.
3760 SqmWall Height:
TechGrid knitted & PVC coated polyester Geogrids with Tensile Strength Of 40 to 250 KN/mFacing:
Discrete Panel FaciaDesign Methodology:
BS 8006: 1995 (Static Condition) FHWA-NHI-00-043 (Seismic Condition)TFIIL’s scope of work:
Detail designs & drawings, supply of Geogrids, Moulds for Discrete Panels, Nonwoven Geotextile & Supervision of construction
Surat Municipal Corporation awarded the work of construction of Flyover at NanaVarchha on Varchha Road in Surat to M/s Rajkamal Infrastructures Pvt. Ltd. TechFab India Industries Ltd was awarded with the project for providing the detail designs and drawings for the Flyover with RS Wall. The Project consisted of RS Wall on Surat Left Side (146m) & Surat Right Wall (155m) and Kamrej Left Side (179m) & Kamrej Right Wall (180.5m) and their abutments. TechFab India Industries Ltd provided the detailed designs and drawings for the project.
After a careful evaluation of the project requirements and the existing site conditions a geogrid reinforced soil wall with discrete panel fascia was considered as the feasible solution.
TechGrid knitted and PVC coated polyester geogrids, manufactured by TechFab (India) Industries Ltd at their state of the art ISO 9001: 2000 certified plant in Silvassa, were used as the soil reinforcement. TechGrid geogrids are manufactured from select grades of high tenacity, high molecular weight polyester yarns using an advanced weft insertion warp knitting process and coated with a specially formulated PVC plastic. The high performance characteristics of these world class geogrids enabled the walls as high as 9m, to be designed safely and economically.
Properties considered in the design of the RS Wall are shown in Table-1.
The fascia type used was a discrete panel type of size 1.48m x 1.48m x 0.18m. Due to the shape and size of the panel it was able to absorb differential settlement of magnitude significantly higher than other panel types.
The borehole and foundation soil test report showed very low friction angle and high cohesion. So in designing the RS wall it was considered that after excavation of 2.25m foundation depth the foundation soil was again excavated for 500 mm depth and replaced with compacted fill according the approved quality. Therefore the Total depth of excavation at the site was taken as 2.75 m from existing service road level. Also, the unsuitable soils were removed and replaced with compacted fill of approved quality where it is required.
The design of the walls was carried out using the BS 8006: 1995 for Static Condition & FHWA-NHI-00-043 for Seismic Condition, which comprised checks for external, internal and global stability under static and seismic conditions.
Construction of the wall was carried out under the supervision of TechFab India Industries Ltd’s supervision.
TechFab India Industries Ltd.
711/712, Embassy Centre,
Nariman Point, Mumbai – 400021
022- 2287 6218