P. R. PATIL COLLEGE OF ENGG & TECH– Amravati

Department Of Civil Engineering

Seminar On

“Applications of Geocell in Geotechnical Engg”

Presented By: Guided By:Mr. Raonak.D.Jain Prof. S.S.Saraf B.E (Civil) Final Year Dept ofCivil Engg

Contents Introduction Applications of Geocell Advantages & Disadvantages of Geocell Case Study Conclusions References

IntroductionGeocells are three-dimensional honeycombed cellular structures that form a confinement system when infilled with compacted soil. Extruded from polymeric materials into strips welded together ultrasonically in series, the strips are expanded to form the stiff (and typically textured and perforated) walls of a flexible 3D cellular mattress as shown in Fig. Geocell come under types of Geosynthetics. This type is mainly being used worldwide. Geocell is also known as Cellular Confinement System(CCS) and are widely used in construction for erosion control, soil stabilization on flat ground and steep slopes, channel protection, and structural reinforcement for load support and earth retention.

Fig.Geocell

Applications of GeocellFollowing are some of the applications of geocell:

Erosion Control using Geocell Ground Stabilization using Geocell Retaining Walls using Geocell Slope & Channel Protection using Geocell Reservoirs & Landfills using Geocell Bearing Capacity Improving

Erosion Control:Soil particles are susceptible to being detached and carried away with concentrated runoff streams, forming rills and gullies that grow with time. As in Fig. Geocell effectively holds slope cover materials in place, thus reducing the potential for erosion.  Cell walls check the runoff streams associated with rainfall, keeping the overall system intact. 

Fig. Erosion Control by using Geocell

Ground Stabilization:Geocell serves as load spreader when loads are imposed upon the system. Furthermore, in many instances it is possible to use locally available inexpensive aggregates in multitude stabilization projects such as: Roads, Accesss lanes, Runways, Parking lots,Railroad, track bedding, Bedding for sewer and water pipes.Generally, in stabilization end-use, the aggregate layer spreads the load imposed upon it, thus reducing the pressure exerted on the subgrade below a critical value as seen in Fig.

Fig. Ground Stabilization

Retaining Walls:In order to stabilize very steep slopes, retaining walls are constructed. Geocell serves as both the facia and the reinforcing element. The cells not only hold the soil in place, they also provide drainage throughout the structure. An additional benefit is that the outer cells can be vegetated shown in Fig. Thus giving the wall a pleasing and environmentally compatible look. The size of the expanded Geocell panels increases the effective thickness of the retaining wall.

Fig. Retaining wall using Geocell

Slope & Channel Protection:The three-dimensional lateral confinement of Geocell along with

anchoring techniques ensures the long-term stability of slopes using vegetated topsoil, aggregate or concrete surfacing . The enhanced drainage, frictional forces and cell-soil-plant interaction of Geocell prevents downslope movement and limits the impact of raindrops, channeling and hydraulic shear stresses. Typical applications include: construction cut and fill slopes and stabilization; road and rail embankments; pipeline stabilization and storage facility berms; channel and coastline structures and this could be seen in Fig.

Fig. Slope Protection

Reservoirs & Landfills:Geocell provides membrane liner protection, while creating stable soil, berms and slopes, for non-slip protection and durable impoundment of liquids and waste. Concrete work is efficient and controlled as Geocell functions as ready-made forms; Geocell with concrete forms a flexible slab that accommodates minor subgrade movement and prevents cracking. In medium and low flow-velocities.

Fig. Reservoir using Geocell

Items Virgin SoilSoil

reinforced with single

layer of Geocell

Soil reinforced

with double layer of Geocell

Bearing Capacity

104 KN/m2 193.75 KN/m2 759 KN/m2

Foundation Size 4200 mm x 4200 mm (RCC

isolated footing)

3000 mm x 3000 mm (RCC

isolated footing)

1500 mm x 1500 mm (RCC

isolated footing)

Concrete Volume

5.36 m3 2.99 m3 1.04 m3

Steel 542 Kg 304 Kg 66 Kg

Geocell Cost - Rs. 17,820/- Rs. 9,460/-

Total Cost Rs. 55,616/- Rs. 48,916/- Rs. 18,568/-

Improving Bearing Capacity:Following table shows the improved results of bearing capacity using geocell:

Advantages & Disadvantages of Geocell in Geotechnical Engg:

• Available in a variety of cell sizes, depths, section lengths and facia colours to meet project needs.• Provides durable protection to impervious liners.• Allows significant sub grade deformation without loss of structural integrity.• Easy to transport and install.• High resistance to tensile stresses, tearing, punching, fatigues.• Environmental friendly material.• Lightweight, Low Cost, High Durability.• It is very economical in use compare to other products.• They increase the reliability of structure, life of structure.

Advantages

Disadvantages

• Long-term performance of the particular formulated resin being used to make the geocell must be assured by using proper additives including antioxidants, ultraviolet screeners, and fillers.

• Handling, storage, and installation must be assured by careful quality control and quality assurance.

Case Study: Location “Guwahati,Assam”Project Brief:

A road was to be build for the access of waste field site. The ground water table was upto ground level which resulted in weak roads and a problem to the heavy vehicles.

Fig. Waste field siteChallenge:

The surrounding water was hampering the movement of the garbage dumping trucks. The garbage trucks were increasingly dumping garbage much before the demarcated area, thus triggering a total mismanagement of the landfill and creating financial losses for the project.

Fig. Heavy truck dumping garbage

Solution:Geocell was preferred as a solution for this project. Geocell System provided a permanent flexible form acting as a series of expansion joints adjusting to the shape and grade of the soil. Geocell installation was complete in 3 days time, whereas the total road was completed in less than 40 days.

Fig. Laying Geocell

Conclusions

Geocell have great potential to be used as cost-effective solutions for several engineering problems.

New construction methodologies have also broaden the applications of geocell reinforced soil retaining wall, which include new facing units and that reduces the construction time, costs and allow better aesthetic conditions for the final structure.

Geocell has been used in a number of applications in environmental project.

References• Agostini, R., Cesario, L., Conte, A., Masetti, M., and Papetti, A.: Flexible gabion structures in earth retaining works, Tech. rep., Maccaferri, Bologna Italy, 1987.

• Bathurst, R. and Rajagopal, K.: Large-scale triaxial compression testing of geocell-reinforced granular soils, Geotech. Test. J., 16, 296–303, 1993.

• Burroughs, D., Henson, H. H., and Jiang, S. S.: Full scale geotextile rock barrier wall testing, analysis and prediction, in: Geocell’

• Chen, R. and Chiu, Y.: Model tests of geocell retaining structures, Geotext. Geomembranes, 26, 56–70, 2008.

• Dash, S. K., Rajagopal, K., and Krishnaswamy, N.: Behaviour of geo-cell-reinforced sand beds under strip loading, Can. Geotech. J., 44, 905–916, 2007.

Any Querie

s

?