FIELD: building, particularly for concreting cast-in-place and precast reinforced concrete structures along with concrete curing temperature regulation.
SUBSTANCE: method involves laying and compacting concrete mix under continuous concrete mix curing temperature control; heating central concrete layers with heating reinforcement when outer concrete layers are in elasto-plastic state. Heating reinforcement is spaced a distance "a" from surface. The heating is carried out simultaneously with surface heat-shielding. Distance "a" is determined as a=δeq(tav-ts)/(ts-ta), m, where δeq - thickness of conditional equivalent concrete layer corresponding to surface thermal resistance, Rs, m; tav - time-average concrete temperature calculated by estimated time of heating directly in heating area, deg; ts - time-average temperature at concrete surface calculated by estimated heating time, deg; δeq is determined as δeq=Rs·λ·F, m, where Rs is heat resistance of rigging with form Rr including thermal resistance Ra of heat transfer from rigging to ambient air, h·deg/kcal; Rs=Rr+Ra=(δr/( λr·F))+(1/(α·F)), h·deg/kcal, where δr is thickness of rigging, m; λr is rigging heat conductivity factor kcal/(m·h·deg), α is rigging surface heat-transfer coefficient kcal/(m2·h·deg), λ is concrete(reinforced concrete) heat conductivity kcal/(m·h·deg); F=1m2 - rigging surface area for thermal resistance calculation, m2. Amount of heat Q used to heat part of member to be heated having length (height) of 1.0 m and cross-sectional width of 1.0 m is determined from Q=(tav-ts)(m+(τ·λ·F/a), where m is constant equal to 60-180 kcal/deg and τ is calculated heating time, hours. The heating reinforcement is heating wires or pipes adapted for hot water circulation.
EFFECT: reduced temperature stresses and prevention of crack formation during structure concreting, as well as possibility to regulate curing temperature.
4 cl, 1 ex, 4 dwg
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Authors
Dates
2006-04-10—Published
2004-08-19—Filed