On the construction of concrete temperature and cracks1. the causes of the cracks8 C% e5 P" y6 F6 K) J; q
Cracks in concrete are a variety of reasons, mainly temperature and humidity changes, brittle and uneven concrete, as well as the structure is irrational, failure of raw materials (such as alkali-aggregate reaction), template deformation, and so on the basis of differential settlement.
6 G. V8 ^9 T& B! i5 h4 ` The concrete to harden off a large number of cement during the hydration heat, the internal temperature rising on the surface caused by tensile stress. Late in the cooling process, due to coagulation on the basis of or be bound by the old, will emerge in the concrete tensile stress." r$ Z7 {& F3 R1 i( H( F
论混凝土的施工温度与结构裂缝" W$ b/ p* Y# F& {# ?! d! S
1.裂缝的原因1 b' w8 X1 e j: g& j
混凝土中产生裂缝有多种原因,主要是温度和湿度的变化,混凝土的脆性和不均匀性,以及结构不合理,原材料不合格(如碱骨料反应),模板变形,基础不均匀沉降等。9 x$ G- k) E J% F5 l
混凝土硬化期间水泥放出大量水化热,内部温度不断上升,在表面引起拉应力。后期在降温过程中,由于受到基础或老混凝上的约束,又会在混凝土内部出现拉应力。
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