The new building material Ultra-high-performance concrete that never cracks has a promising application future
Ultra-high performance concrete (UHPC) is a new type of cementitious composite material developed in the last thirty years, which has ultra-high mechanical properties and durability, as well as good toughness, adhesive properties and impact and fatigue resistance.In recent years, with the continuous maturity of UHPC preparation technology, the superiority of its performance has been gradually recognized by the public, and UHPC has become a research hotspot in the field of concrete, which is widely used in structure, decoration, reinforcement, quick repair, paving and joint filling.
 | Ultra-high performance concrete, in the international are the kind of compressive strength of 150MPA or more, and has a super high toughness, ultra-long durability of cementitious composite materials collectively. Among them, more representative of the ultra-high performance concrete materials for the activated powder concrete RPC, early proposed by the French scholars in 1993, mainly by the silica fume, cement, water reducer, fine aggregate and steel fibers and other materials, in accordance with the principle of the greater compactness of the construction, which can make the material internal defects (pores and micro-cracks) reduced to less. It is the most innovative cementitious engineering material of the last three decades, and a major leap forward in engineering material performance.
As a kind of special engineering material with ultra-high strength, toughness and high durability, UHPC has good application prospects in the fields of national defense engineering, marine engineering, nuclear industry, special security and protection engineering, and municipal engineering. Tests have proved that its flexural strength is three times that of ordinary C50 concrete, shrinkage is reduced by 50%, and it remains intact after 700 freeze-thaw cycles, which is known as the concrete that "never cracks". |
UHPC has very low permeability to gases and liquids in a non-cracked state; in a high strain and micro-cracked state, the permeability of UHPC can also be kept at a very low level, and the micro-cracks also have a good self-healing ability, so the UHPC structure has a high durability potential, which has been proved by 15 years of exposure tests in harsh environments to date.The durability and weathering performance of UHPC is far beyond that of The durability and weatherability of UHPC far exceeds that of other structural engineering materials (steel, aluminum, plastics, etc.).