The Study Of Natural Cinder Preparation And Properties Of Lightweight Aggregate Concrete

With modern civil engineering structure increasingly towards the direction of large-span,overloading,tall,especially for large span bridge needs,ordinary concrete are the major,the worse performance of heat preservation and heat insulation faults,make its application in the field of engineering in some limitations.Compared with normal concrete,lightweight aggregate concrete has light weight,good vibration resistance,crack resistance,fire resistance,good,and many other advantages,partial structure with lightweight aggregateconcrete in construction instead of the normal aggregate concrete has the very important value.Our country is a country with many volcanoes,the cinder storage of the parts is bigger,the natural cinder of lightweight aggregate concrete is a good raw material.In cinder rich reserves of area with its light weight aggregate concrete used for practical engineering,can save a lot of energy for our country,and can meet the requirements of building energy efficiency and reduce the structure weight,can achieve the goal of green environmental protection.But at the moment,the whole light cinder of lightweight aggregate concrete study is less,this paper makes the full light of lightweight aggregate cinder concrete system research,the main conclusions are as follows:(1)By changing the different dosage of single grain grade cinder aggregate volume to change the packing density of the aggregate and sand ratio,and test the work of the new mix of cinder concrete performance and mechanical properties of the hardened concrete.Research shows that: when the maximum nominal size of 16 mm single grain cinder with the nominal maximum particle size of the aggregate level of 10 mm of single grain grade cinder two graded aggregate volume ratio of 7:3 always concrete compressive strength is the highest;Cinder and volcanic sand coarse aggregate 7:6 for fine aggregate volume,the sand rate was 46%,cinder lightweight aggregate concrete with best workability and mechanical properties.(2)Using four different preparation of lightweight aggregate concrete mixing process,by comparing the workability,strength and shrinkage of concrete performance,the micro structure of the research on the concrete mixing process.Research shows that: the net paste wrapped stone mixing technology can significantly improve the strength of concrete;Contrast prewetting and not wet mixing process,prewetting mixing ratio not prewetting mixing intensity is high,the fresh concrete slump little slump loss,1h.(3)By confecting ratio and strength grade of lightweight aggregate concrete and alllight cinder haydite lightweight aggregate concrete,the cinder lightweight aggregate concrete with ordinary difference of the performance of the haydite lightweight aggregate concrete.Research shows that:choose the same strength grade,with lightweight aggregate concrete mixture ratio of cinder and haydite lightweight aggregate concrete,two types of aggregate 7d,28 d compressive strength is;Cinder frost resistance,permeability resistance of lightweight aggregate concrete are worse than haydite lightweight aggregate concrete;Electric flux haydite lightweight aggregate concrete is far less than the volcano slag lightweight aggregate concrete;Early haydite lightweight aggregate concrete and ordinary aggregate concrete as contracts,while the early volcano slag lightweight aggregate concrete expansion.(4)test with different water/cement ratio,different levels of prewetting cinder preparation of concrete,and a set of general haydite aggregate doing parallel experiment were compared.Research has shown that early shrinkage haydite lightweight aggregate concrete is bigger,the opposite of lightweight aggregate concrete and cinder,early expansion;Water-binder ratio decreases,and the compressive strength increases,the early shrinkage increases;Not prewetting mixing cinder aggregate fresh concrete early wet bilge,larger prewetting fresh concrete mixing of cinder aggregate early wet bilge is small;Use volcanic sand instead of river sand of ordinary concrete can significantly reduce the early shrinkage of concrete,the expansion of the early.