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38 NOVEMBER 2017 MATERIALS PERFORMANCE NACE INTERNATIONAL: VOL. 56, NO. 11 above the bridge deck by small wood blocks. The anodes were kept covered with electrolyte solution at all times. Figure 5 shows the compart mentalized ponding frames and one of the dc generators used in the experiment. The frame in the back- ground contains the electrolyte, resin, and anodes. Electrical contact was made with the top layer of the rein- forcing steel in the treatment area through 6 x 25 x 200 mm (0.25 x 1 x 8 inch) mild steel studs which were arc welded to the rebars. The rebars were exposed by coring along the berm side of the treatment area. Direct current power leads were C L A S S I C attached to the rebar contact studs and to vertical studs that were welded to the titanium anodes in each compartment. Electrical power was supplied by two trailer mounted, gaso- line drive, dc generators. A schematic of the experimental technique is shown in Figure 6. Treatment Conditions. Each 3.7 m 2 (40 ft 2 ) area was served by 2 dc generators, one generator supplying power to a 1.9 m 2 (20 ft 2 ) area. In all cases, effort was made to maintain genera- tor output at the maximum rates capacity of 120 volts. In prac- tice the voltage generally fluctuated between 10 0 and 120 volts. Areas 1 and 2 (Figure 3) were treated for 12 hours, while Areas 3, 4, and 5 were treated for 24 hours. The ion exchange resin was omitted in the treatment of Area 4. This resulted in a noticeable odor of free chlorine above the electrolyte ponds during the treatment period. The temperature of the electrolyte ponds was measured during treatment. In addition, temperature of the concrete deck was measured by use of thermocouples inserted into small holes drilled into the concrete. Effort was made to moni- tor pavement tempera ture just above a rebar and about 38 mm (1-1/2 inches) below the concrete surface, midway between rebars. Full time monitoring of the experiments was carried out throughout the treatment. Data were obtained on applied cur- rent and voltage, and on slab and electrolyte temperature, as a function of treatment time. Following completion of the electrochemical treatment, the electrolyte/resin solution was pumped off and 75 mm (3 inch) core samples were taken from the treated area. The resin was FIGURE 7 — Potential scan of treatment area 24 hours after final treatment (negative values). FIGURE 8 — Potential scan of bridge deck treatment area 1 week after final treatment. FIGURE 9 — Potential scan of bridge deck treatment area 1 month after treatment.