Experimental Satudy Of HTRB600 High-strenth Steel High Temperature Mechanical Properties

With the advent of science and technology,Concrete structure design code in China also in further revision,specification for design of concrete structures(GB50010-2010)revision,listed the high strength steel,promoted the engineering applications of high strength steel.Many scholars also carried out the study of the properties and application of high strength steel.This paper takes HTRB600 high strength steel bar as the research object,the experiences in different temperatures and after the different temperatures study of mechanical performance,the main contents are as follows:1、The mechanical properties under different temperatureThis paper choose HTRB600 of jiangsu shagang group co.,LTD.Produces high strength hot rolled with crescent ribbed bars(25 mm)diameter as the parent metal processed into a total of 9 set of standard parts Including 1 normal group,the rest 8groups of high temperature heating,temperature,respectively 150℃,225℃,300℃,400℃,500℃,600℃,700℃ and 800℃.The conclusions are as follows:(1)With the increase of temperature,HTRB600 the yield strength of high strength steel in high temperature ultimate strength elastic modulus reduction of elongation and mechanical properties such as ultimate strain change rule About 400 ultimate strength decrease,ultra-high temperature after 600,ultimate strength sharply lower;About 300 significantly lower yield strength;Reduction of area with rise before the rise of temperature,the peak in 500.With the increase of temperature elongation increase,more than 500,elongation increased rapidly.(2)HTRB600 under the high temperature ultimate strength of high strength steel Mechanical properties such as yield strength and elastic modulus degenerate rule and other low level of ordinary steel and the degradation law of HRBF500 steel,with the rising of temperature is reduced,but the reduction value is large;HTRB600under high temperature,high strength reinforced elongation increased with the rising of temperature,similar to ordinary steel cold rolled steel and cold drawn steel bar,differ with HRBF500 steel change rule.2、Mechanics performance after different temperaturesThe length of 450 mm,16 mm diameter,a total of 18 group of reinforcement,heating temperature 150℃,250℃,400℃,550℃,700℃and 400℃ respectively;cooling in three ways :natural cooling、swamp cooling and furnace cooling,different heating and cooling temperature on the mechanical behavior of steel.(1)After different high temperatures and different cooling effect,HTRB600high-strength steel yield strength,ultimate strength,elastic modulus and elongation mechanical performance parameters are changed,the change rule by the experience of the influence of temperature and cooling temperature effect is relatively low(550℃and below),the reinforcement mechanics performance change is not obvious;Temperature effect is relatively high(above 625℃),the reinforcement mechanics index change is larger When the temperature is higher(700℃,800℃and 850℃),the different cooling methods on steel had a greater influence on the mechanical properties,which adopts the immersion cooling method and the other two cooling way is large.(2)High temperature are obtained by least square method after cooling HTRB600 high-strength steel yield strength than ultimate strength elastic modulus and elongation ratio under different heating temperatures and different cooling ways of expression of the performance parameters.