混凝土 土木工程材料PPT幻灯片.ppt

土木工程材料
第5章
主讲: 徐清
混凝土
Neville . (UK) wrote in “Properties of Concrete”
Concrete and steel are the monly used structural materials. They plement one another, and pete with one another so that structures of a similar type and function can be built in either of the materials . And yet, the engineer often knows less about the concrete of which the structure is made than about the steel.
……
These facts must be borne in mind by the designer, as careful and intricate design can be easily vitiated if the properties of the actual concrete differ from those assumed in the design calculations. Structural design is only as good as the materials used.
From the above it must not be concluded that making good concrete is difficult.
……
‘Bad’ concrete – often a substance of unsuitable consistency, hardening into a bed, non-homogeneous mass – is made simply by mixing cement, aggregate and water.
Surprisingly, the ingredients of a good concrete are exactly the same, and it is only the ‘know-how’, backed up by understanding, that is responsible for the difference.
混凝土的分类
凡由胶凝材料、粗细骨料、水按适当的比例配合、拌合制成混合物,经一定时间后硬化而成的人造石材,叫做混凝土
重混凝土
普通混凝土
轻混凝土
按表观密度
普通混凝土
高强混凝土
超高强混凝土
按强度等级
混凝土
泵送混凝土
喷射混凝土
真空脱水混凝土
碾压混凝土
压力灌浆混凝土
太阳能养护混凝土
按施工工艺
防水混凝土
耐热混凝土
耐酸混凝土
纤维混凝土
聚合物混凝土
按功能或材料
混凝土
混凝土作为一种建筑材料
优点
.


4. 与钢筋有牢固的粘结力
。
缺点
,属于一种脆性材料。
。
,从而延长了施工期。