Experimental Study On The Early Strength Of Non-steam Curing Concrete

Now,along with the social development and the urbanization level of deepening,China’s demographic dividend gradually disappear,labor shortages.In recent years,our country began to pay more and more attention to the present situation of the low efficiency of high energy consumption construction industry,sum up experience,to carry out the national conditions,follow the European and American developed country,gradually building industrialization in China.Prefabricated prefabricated is the core and foundation,building industrial prefabricated prefabricated production at present stage,is still using the old casting production process,namely the prefabricated production is completed,with the method of the steam curing,fast to form removal strength member.But facing the increasingly serious environmental problem in our country,steam curing method also brings disadvantages.First of all,this study developed an early strength type poly carboxylic acid was synthesized high efficiency water reducing agent PC-Z,water reducing rate is 30 % ~ 35 %,the water reducing agent against sulfate aluminate cement and Portland cement has good adaptability,and compared with common water reducing agent,has an obvious effect of early strength.Use this early strength type efficient jianshuiji PC poly carboxylic acid,Z can be configured out of the water cement ratio 0.32 under low water cement ratio of concrete,at the same time of improving concrete strength grade,early strength also increased significantly.Then,this study discusses,in the early strength poly carboxylic acid type high efficiency water reducing agent under the action of PC-Z,gelled material,mineral admixture of precast concrete from steam raises a gender can influence.Get the combination of the best results for the standard curing temperatures: use 5% sulphur aluminate cement and double mixing mineral powder,15 % 10 % amount of fly ash to replace cement,can rise to ensure strength,improve the workability,the action of saving cement.In the condition of low temperature andmineral powder and fly ash can affect concrete early strength,so choose 10% ~ 15% ultrafine mineral powder amount to replace cement,can effectively improve the early strength of concrete.Finally,this study to shandong dry yuan ze fu technology co.,LTD.,the actual production for the project example,the law,with the combination of experiment can developed in summer(high temperature),age season(temperature)and winter(low temperature)three seasonal temperatures,get free precast concrete pipe,can make 16 h from pipe concrete strength is greater than 22.5 MPa,satisfies the requirement of practical production.Finally,this research institute developed economy analysis,pipe concrete are calculated this product the overall price,lower than ordinary steam curing of concrete.If the research results will be used in practical engineering of precast concrete,can be in the case of without steam curing,improve the early strength of concrete,to speed up the mold flow,saving the cost of materials and the enterprise operating costs,and reduce the energy consumption and reduce environmental pollution,economic benefit and environmental benefit is remarkable.