Experimental Study On Green Concrete Based On Whole Solid Waste Materials

With great attention were paid on the environment issue by our government recently,environmental and sustainable development has become the investigative focus of every industrial field.A large amount of sand aggregate are needed as the raw material of concrete for making building construction during the rapid development of urbanization.While excessive exploitation of these sand aggregate has ruined our harmonious living environment due to the fact that sand aggregate belongs to the limited natural resource.In addition,cement is a high energy consumption product which is needed for making concrete.Each ton of cement produced will release 0.5-1ton of carbon dioxide.Huge carbon emissions make our living environment under great pressure.Therefore,this thesis developed the study of environmental concrete which was full use of solid waste material from two aspects.One is the cementing material,the other one is aggregate.As a result of this study process,this thesis provided the strong technology support for making environmental and sustainable concrete by taking advantage of alkali to excite cement material,recycled aggregate and TBM gravel aggregate.The main works and the conclusions are as following:First of all,this thesis began with the investigation and study on the activating agent of slag-based cementing material.The study selected the sulphoaluminate cement-anhydrite,petroleum coke slag and carbide slag anhydrite to investigate the content and the activating effects.The research demonstrated a fact that petroleum coke slag is a better slag activating material than sulphoaluminate cement-anhydrite and carbide slag anhydrite.The cementing material compressive strength will reach 33 MPa when the content of petroleum coke slag is 17%.It analyzed main mineral of cement which is known as the alkali activating agent material through XRD and SEM tests.The research shows that the main products are two water gypsum,calcium vanadium and silicic acid gel etc..Based on the activating agent investigating result,this thesis pointed out that slag flyash-petroleum coke slag-cementing material system investigate plan.This thesis focused on the flyash content and maintenance system's influence to the cement material compressive strength development rule.It turns out to be the case that the more the amount of flyash content is,the lower the compressive strength of cementing material is.When the water binder ratio is 0.5and the flyash content is 50%,the 28 d compressive strength is about 20 MPa.It is about50% of that without flyash.The lower the water binder ratio is,the bigger the compressive strength of cementing material is.When the water binder ratio is 0.3,the3 d,7d and 28 d compressive strength of cementing material with common 50% flyash added in it separately are 20 MPa,45MPa and 50 MPa.The higher the steam temperature and the longer the steam time are,the greater the compressive strength of the cementing material is.When the content of flyash is 50%,the compressive strength of steam cured at 80 ? for 2h and 4H was 10 MPa and 17 Mpa respectively.At last,this thesis developed the research of solid waste environmental concrete by taking advantage of slag-flyash-petroleum coke slag cementing material,recycled aggregate ? and TBM gravel.The research shows that the compressive strength of concrete will increase accordingly when the cementing material consumption is increased.When the consumption of each cubic meter recycled aggregate ?concrete is500 kg,the 7d compressive strength is 10 MPa,the 28 d compressive strength is 18 MPa.Its' function will apparently increase when the TBM gravel is used as aggregate.Compared with recycled aggregate?,when the 28 d compressive strength is certain,the loss rate of freeze-thaw quality is close to 0.This thesis is aim to provide technology support for the spread and application process of low strength grade floor,countryside road and solid waste concrete productions.