Research On The Properties Of Highperformance Cement-based Rapid Repairing Materials

Since China’s reform and opening up, with the constant improvement of the economic level, people has higher requirement to the infrastructure. cement concrete pavement, as a kind of high strength, high durability, good stability, strong bearing capacity of the highway, is widely used in the construction of urban roads and airports. But in recent years due to the increasing traffic volume and the overload phenomenon, the service life of concrete pavement was influenced seriously. Concrete pavement cracking, potholes, missing angle, the stage of fault diseases occur, if the fault was not timely repaired, disease will be increased rapidly, and accelerate the damage of concrete pavement, endangers safety. Ordinary patching material due to the long construction period, poor durability after repair faults can’t meet the requirements, and new type of rapid repairing materials due to the expensive, poor construction flaws, cause it can’t be a wide range of promotion and use, to develop a fast and efficient, low cost, convenient construction of high performance pavement rapid repair materials.Based on rapid hardening sulphoaluminate cement and ordinary Portland cement composite as basic gelling system, with the equivalent substitution method of adding silica fume, slag, lime, fly ash, formed four kind of mineral admixture to composite gel system, adopting three quartz sand particle size grading in proportion as aggregate, by adding an appropriate amount of retarder, early strength agent, water reducing agent and other admixtures, makes a rapid hardening, early strength, good workability, resistance to dry shrinkage, crack resistance, the late strength fail shrinkage of repair mortar, the initial setting time is from 30 min to 40 min, final set time is from 40 min to 50 min, to ensure the enough construction time; more than 2hflexural strength is 7.0MPa and 2h compressive strength more than 30.0MPa, meet the requirement of the fast repair roads, make the traffic open as soon as possible.In the development process of the mortar, the following research work had be done: initial setting time is more than 30 min in mortar and mortar under the premise of 2 h mechanical properties, determined the retarder and the optimum content of early strength agent; is studied through the orthogonal experiment, Silica fume, slag, quick lime, fly ash influence on fluidity of mortar and mechanical properties, according to the test dat a analysis, put forward the optimum content of four kinds of mineral admixtures, and determined the late guarantee mortar strength not shrink dosage of mineral admixtures is the lowest; Silicon ash and lime is studied on the mechanical properties of mortar, the influence of the early expansion and drying shrinkage performance, put forward a more reasonable silicon ash and lime content; Was studied in view of the early stage cracking of mortar, can be dispersed emulsion powder and polypropylene fiber on early repair mortar cracking performance, the influence of confirmed that polypropylene fiber can inhibit the early cracking of mortar, and put forward the optimum content of polypropylene fiber, solve the problem of the early cracking of repair mortar.