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 Introduction:- Keystone is a mechanical stabilized earth wall MSEW which used to retain soil from one side, it's less cost than concrete walls. Material  1-Keystone Blocks 2-Fiberglass Pins 3-Geo-grids 4- Back-filling Material 5-Concrete pad  Different type of Geogrid:  TT045 can carry load till 45KN/m. TT060 can carry load till. 60KN/m. TT090 can carry load till 90KN/m.  TT120 can carry load till 120KN/m.  TT160 can carry load till. 160KN/m. Method Statement  1) Place HDPE Geogrids on top of the compacted soil. HDPE Geogrids are installed from the front on top of the fiber glass pins (which penetrates the grid) and from to back, Geogrids are fixed horizontally using a steel bars.  2) Lay down the precast concrete units on top of a PC foundation at a level that is a Minimum of 5% from the wall height and reach 10% (buried height) to prevent any lateral movement .  3) Put the layers of Geotextile.  4) Backfilling using fine gravel behind the wall for a distance of 50 cm, max size o

Bolt grades Bolt Grade 4.6 4.8 5.6 5.8 6.8 8.8 10.9 Fy t/cm2 2.4 3.2 3.0 4.0 4.8 6.4 9 Fu t/cm2 4.0 4.0 5.0 5.0 6.0 8.0 10.0   Ordinary Bolts High strength bolts *Revit have two grades:   grade 1    Fu 5t/cm2, grade2 Fu 6t/cm2 e1= end distance                                                                                                        e2= edge distance                                                                                              s= spacing