原位化学发泡轻集料混凝土的制备与性能表征

The preparation and characterization of the lightweight aggregate concrete by situ chemical foaming

以粗、细膨胀珍珠岩分别为轻集料和发泡剂载体,H_2O_2(浓度30%)为化学发泡剂,明胶为稳泡剂,制备原位发泡轻集料混凝土试样,并对其性能进行了表征。当发泡剂掺量为5.6%时,轻集料混凝土试样的体积密度和抗压强度均随着稳泡剂明胶掺量的增加而增大,当稳泡剂掺量为1.5%时,可制得体积密度为700 kg/m^3的轻混凝土试样,该试样的28 d抗压强度达到9.9 MPa;而稳泡剂掺量为1.0%的试样28 d抗压强度仅为3.4 MPa。另外,发泡剂掺量为5.6%的轻集料混凝土试样导热系数为不发泡试样的1/2。

The lightweight aggregate concrete （LAC） specimens were prepared using the method of chemical foaming in situ. In the foaming process,the expanded perlites were used as lightweight aggregate（coarse） and foaming agent carrier（fine） respectively,the H202 （30%） was used as foaming agent （.FA）, and the gelatin was used as foam stabilizer （FS）. The properties of the resulting LAC specimens were characterized systemically. After chemical foaming in situ,it was found that both the bulk density and 28 d compressive strength（CS） of the resulting LAC specimens were increased with the increase of adding amount of FS. For the resulting LAC specimen with FA amount of 5.6% and FS amount of 1.5%,it had the bulk density of 700kg/m3 and 28 d CS of 9.9 MPa,while the specimen with FS amount of 1.0% only had the 28 d CS of 3A MPa. As compared with LAC specimen without foaming, the thermal conducing coefficient was deceased one time for that of the resulting LAC specimen with FS of 5.6%.