CASES

 

 

Project 01
Jobsite: Condominium garage in the Northern part of São Paulo area.
Problem: Leaks into expansion joints and cold joints. See the example.
History: For 8 years, several waterproofing attempts have been made, including the total change of asphalt membrane placed during the construction and further application of neoprene and cementitious materials to the upper joints. Without achieving satisfactory results, because leaks returned after some time, AFFA Químicos Ltda. was hired for solving problem.
Solution: The application team suspected that leaks were not totally due asphalt membrane failures, but they could also be originated at the expansion joints and/or building sidewall.

One of joint ends pass under the garden, in a perpendicular way to the building’s external wall. The joint also starts and ends at the external wall.
The injection of Inject Plus MAX Gel showed that the suspicion was right, once the gel showed up mainly at the sidewalls, indicating the leak path and sealing it for good.

Project 02
Place: effluent treatment tank of petrochemical plants.
Problem: Groundwater mixed with oil leaks, which hindered the tank coating with vinyl ester resin. Therefore, the work has not been completed.
History: For 6 months, several applications of resins and crystals have been made to the surface, with a certain degree of success. At the top of the tank, water entered with low pressure; at this point, the crystals have sealed the leakage. However, at the bottom and at the end of sidewalls, the leakage pressure extruded the sealing resin layer and oil stains appeared, and hindered the coating application.
Solution: Due the presence of oil, the chosen product should have two essential properties:

• High adherence to oiled substrate.
• Ability to extrude the oil from the concrete.

The product chosen was Inject Plus PWG Gel, due its elastomeric additives, has high capacity for cleaning and adhering to the contaminated substrate. The technique used was the “Curtain Injection”, creating a “skirting” of waterproof gel between the tank wall and the ground, always injecting the internal side of the tank. The bottom has dried ,and the vinyl ester coating was applied without problems.


Project 03
Place: Office building in the Northern São Paulo area, with slab built with pre-stressed concrete plates.
Problems: Leaks on the 20th floor, on the beams sides and joints with the columns located at the floor center.
History: The alternatives tested over several years have not showed satisfactory results; the installation of roof gutters, application of neoprene sealers etc. have always provided the same result: the leakage return after some months.
Solution: AFFA Químicos Ltda.’s engineers assessed the structure and concluded that 80% of the leakage causes were due water entering through the external building sides and at the columns joints with the pre-stressed concrete slabs. Therefore, a waterproofing solution with traditional methods would not have been 100% effective. The leak in the middle of the office hall was caused by the same source, and the water ran through tension’s distribution channels of pre-stressed concrete plates. The product injected from the bottom to the top, Inject MAX Gel, showed that the initial appraisal was correct. It was possible to see the gel going out of the columns top and on the terrace, and thus sealing the leakage source.
 

Project 04
Place: Textile industry in Bom Retiro, São Paulo area.
Problem: Leaks over machineries at several points of the main room.
History: The building has been renovated not long ago, and a traditional treatment would be expensive and little practical, because the terrace was covered with grass and there was a large area to be treated.
Solution: The chemical injection treatment with Gel Inject MAX once again was efficient. In this case, the gel also searched for the leakage sources and showed that not all of them originated from the upper area, but also from the joints of the upper slabs with the sidewalls, i.e., at the points where a surface waterproofing would not reach to cover.