When freshly poured concrete is exposed to freezing temperatures before it has set, the water within the concrete can freeze. This expansion disrupts the setting process, delays chemical reactions necessary for hardening, and increases the volume of pores within the hardened concrete, which weakens its overall structure. If the concrete manages to reach an appreciable strength before it freezes, the damage can be somewhat mitigated.

To counteract the negative impacts of cold weather, ensuring an adequate temperature of the concrete during and after placement is key. This is often achieved by using warm mixing water, heated aggregates, and modifying the mix with Type III cement or accelerators. This can also be done by insulating the concrete from the cold with thermal barriers, or actively heating the space around the concrete using methods like exhaust steam or jacket-like steel forms with circulating hot water.

Monitoring the concrete temperature with thermometers or thermocouples is essential, especially in strategic locations prone to rapid cooling, such as corners and exposed surfaces. Adjustments to insulation and heating may be necessary based on ongoing temperature assessments to accommodate sudden drops in ambient temperature.

Bölümden 10:

article

Now Playing

10.12 : Cold Weather Concreting

Elasticity, Creep, and Shrinkage in Concrete

31 Görüntüleme Sayısı

article

10.1 : Elasticity in Concrete

Elasticity, Creep, and Shrinkage in Concrete

50 Görüntüleme Sayısı

article

10.2 : Dynamic Modulus of Elasticity of Concrete

Elasticity, Creep, and Shrinkage in Concrete

159 Görüntüleme Sayısı

article

10.3 : Creep in Concrete

Elasticity, Creep, and Shrinkage in Concrete

54 Görüntüleme Sayısı

article

10.4 : Factors Affecting Creep

Elasticity, Creep, and Shrinkage in Concrete

70 Görüntüleme Sayısı

article

10.5 : Effects of Creep

Elasticity, Creep, and Shrinkage in Concrete

56 Görüntüleme Sayısı

article

10.6 : Shrinkage in Concrete

Elasticity, Creep, and Shrinkage in Concrete

43 Görüntüleme Sayısı

article

10.7 : Drying Shrinkage

Elasticity, Creep, and Shrinkage in Concrete

39 Görüntüleme Sayısı

article

10.8 : Carbonation Shrinkage

Elasticity, Creep, and Shrinkage in Concrete

78 Görüntüleme Sayısı

article

10.9 : Types of Non-structural Cracks in Concrete

Elasticity, Creep, and Shrinkage in Concrete

77 Görüntüleme Sayısı

article

10.10 : Mass Concreting

Elasticity, Creep, and Shrinkage in Concrete

35 Görüntüleme Sayısı

article

10.11 : Hot Weather Concreting

Elasticity, Creep, and Shrinkage in Concrete

40 Görüntüleme Sayısı

JoVE Logo

Gizlilik

Kullanım Şartları

İlkeler

Araştırma

Eğitim

JoVE Hakkında

Telif Hakkı © 2020 MyJove Corporation. Tüm hakları saklıdır