Ferrocement Tank Design.pdf

Ordinary Portland Cement (O.P.C.), Portland Puzolona Cement (P.P.C.), and High-early-strength Cement can be used.
Sand: Medium coarse sand with grading, free from chemical pollution and silt contents within 3% of volume.
Wire Mesh: Hexagonal, square welded, and woven square mesh can be used, with woven square mesh preferred for water tanks.
Chemical Admixtures: Pore-sealing compound and plasticizer can be added to mortar.

Design and Construction

Tank dimensions: 12m3 and 15m3 units with diameter of 2.5m, height of 2.5m and 3.11m, and wall thickness of 30mm.
Reinforcement: 6mm skeletal steel rods sandwiched between two layers of 12.5mm square woven wire mesh.
Construction: Can be carried out by unskilled labor in four days, with excellent water tightness.

Casting of Roof for Tanks

Ferrocement roofs can be precast in one piece or 4-6 pieces, with jointing method same as for wall segments.
Two types of joints between wall and roof can be adopted.

Do's and Don'ts for Ferrocement Tanks

Use best quality materials, avoid loose pockets or honey-combed areas, and cure tanks for minimum 10 days.
Clean tank from inside at least twice a year, keep top of tank clean, and construct tank at higher point for proper drainage.
Avoid using corrected steel or mesh, old stocks of cement, and chemically polluted water.
Do not paint drinking water tank without confirmation of specifications laid down by Indian Standard Specifications 158 (I.S.–158).

Reinforcement Cage for Roof of Ferrocement Water Tanks

Wire mesh reinforcement with 1 layer of 22G×½”×½” G.I. woven mesh on inside and outside surfaces.
Rise of roof dome varies with tank diameter, ranging from 10cm to 18cm.