TYPES OF CONCRETE Cùng với bê tông thông thường tổng hợp thô, xây dựng cũng được sử dụng loại bê tông khác nhau từ đặc thù về cơ cấu, thành phần và tài sản. Có những hạt mịn bê tông, bê tông có độ bền cao, bê tông, sửa đổi polymer phụ gia và chất xơ bê tông cốt thép, bê tông cho các mục đích đặc biệt - hydrotechnical, độ bền cao, chịu nhiệt, phải đối mặt và bê tông để bảo vệ bức xạ hạt nhân trong chương | CHAPTER 8 TYPES OF CONCRETE L. Dvorkin and Along with ordinary coarse aggregate concrete in construction are also used types of concrete which differ from their structural peculiarities composition and properties. There are considered fine-grained concrete high-strength concrete concrete modified by polymer admixtures and fiber reinforced concrete concrete for special purposes - hydrotechnical high-strength heat-resistant facing and concrete for nuclear radiation protection in the given chapter. Fine-grained concrete Maximum coarseness of the aggregate in fine-grained concrete is 10 mm. Sand concrete that does not contain coarse aggregate is prevalent type of the concrete. Y. Bagenov suggested dependence of sand concrete strength as empirical formula R A W AR c - 7 Where A is a coefficient for high quality materials A medium quality - and low quality - Va is volume of entrained air C W -contents of cement and water kg m3 Rc -strength of cement MPa. Numerous experimental data shows that there are a lot of factors besides cement-water ratio C W cement strength and aggregate quality such as placeability of fresh concrete hardening conditions presence and quantity of admixtures etc. which make influence on fine grained concrete strength. Quality of the aggregate for fine grained concrete make much more influence on its basic properties than those for conventional heavy concrete. According to data replacement coarse sand for fine sand in concrete can reduce strength for and sometimes in times. Concrete placeability parameter defines sand - cement ratio at given watercement ratio Fig. . .
