Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Chemical Treatment of Soil.
#1
Chemical Treatment of Soil.

Treating the soil beneath the building and around the foundations with a soil insecticide is a preventive measure. The purpose of the treatment is to create a chemical barrier between the ground from where termites come and woodwork or other cellulosic materials in the buildings. The following chemicals conforming to relevant Indian Standard in water emulsion are effective when applied uniformly over the area to be treated.

Chemical Chlorpyrifos 20 EC
Relevant Indian Standard IS 8944
Concentration by Weight,percent(active Ingredient) 1.0

Chemical - Lindane 20 EC
Relevant Indian Standard - IS 632
Concentration by Weight,percent(active Ingredient) -1.0

A: Treatment for Masonry Foundations

The bottom surface and the sides (up to a height of about 300 mm) of the excavation made from masonry foundations and basements shall be treated with the chemical at the rate of 5 lt/m2 surface area.

[Image: termite1.jpg]

B: Treatment for Masonry Foundations.

After the masonry foundations and the retaining wall of the basements come up, the backfill in immediate contact with the foundation structure shall be treated at the rate of 7.5 l/m2 of the vertical surface of the sub-structure for each side. If water is used for ramming the earth fill, the chemical treatment shall be carried out after the ramming operation is done by rodding the earth at 150 mm centres close to parallel to the wall surface and spraying the chemical emulsion at the above dosage.

[Image: termite2.jpg]

C: Treatment at Junction of the Wall and the Floor

Special care shall be taken to establish continuity of the vertical chemical barrier on inner wall surface from ground level (where it had stopped with the treatment described in 7.2.2) up to the level of the filled earth surface. To achieve this, a small channel 30 mm x 30 mm shall be made at all the junctions of wall and columns with the floor (before laying the sub-grade) the rod holes made in the channel up to the ground level 150 mm apart and the iron rod moved backward and forward to break up the earth and chemical emulsion poured along the wall at the rate of 7.5 l/m2 of vertical wall or column surface so as to soak the soil right to the bottom. The soil should be tamped back into place after the operation.

[Image: termite3.jpg]

D: Treatment of Top Surface of Plinth Filling.

The top surface of the consolidated earth within plinth walls shall be treated with chemical emulsion at the rate of 5 l/m2 of the surface before the sand bed or sub-grade is laid. If the filled earth has been well rammed and the surface does not allow the emulsion to seep through, holes up to 50 to 75 mm deep at 150 mm centres both ways maybe made with 12 mm diameter mild steel rod on the surface to facilitate saturation of the soil with the chemical emulsion.


E: Treatment of Soil Along External Perimeter of Building

After the building is complete, the earth along the external perimeter of the building should be rodded at intervals of 150 mm and to a depth of 300 mm. The rods should be moved backward and forward parallel to the wall to break up the earth and chemical emulsion poured along the wall at the rate of 7.5 l/m2 of vertical surfaces. After the treatment, the earth should be tamped back into place. Should the earth outside the building be graded on completion of building, this treatment should be carried out on completion of such grading.


F: Treatment of Soil Under Apron Along External Perimeter of Building

Top surface of the consolidated earth over which the apron is to be laid shall be treated with chemical emulsion at the rate of 5 l/m2 of the surface before the apron is laid. If consolidated earth does not allow emulsion to seep through, holes up to 50 to 75 mm deep at 150 mm centres both ways may be made with 12 mm diameter mild steel rod on the surface to facilitate saturation of the soil with the chemical emulsion.


G: Treatment for RCC Foundations and Basement

In the case of RCC foundations, the concrete is dense being a 1:2:4 (cement: fine aggregates: coarse aggregates, by volume) mix or richer, the termites are unable to penetrate it, it is therefore, unnecessary to start the treatment from the bottom of excavations. The treatment shall start at a depth of 500 mm below the ground level except when such ground level is raised or lowered by filling or cutting after the foundations have been cast. In such cases, the depth of 500 mm shall be determined from the new soil level resulting from the filling or cutting mentioned above, and soil in immediate contact with the vertical surfaces of RCC foundations shall be treated at the rate of 7.5 I/SQM. The other details shall be as laid down in.

[Image: termite7.jpg]
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)