Research On Construction Technology Of Super High-Rise Pumping Concrete

With the increase of building height and the development of super high-rise pumped concrete construction technology,"Technical regulations of concrete pumping construction" has been unable to meet the actual construction’s requirements.Under the premise of meet the pumping rules in the concrete work,there are still a lot of blocking pipe problem.The reason mainly has the following: Firstly,the pumpability of concrete is not strong and mixture ratio is not standard;The second,the pumping pressure calculation formula of regulation is not applicable to high strength and high fluidity concrete;The last,construction control key points and matters needing attention of regulation is also imperfect.Therefore,in order to solve the above problem,this paper is based on the situation of blocking pipe in a super-high project,with reference to the project of concrete solutions,by adding a new material of graphite powder and changing the dosage proportion to formulate the C60 concrete with good pumpability,in order to reduce blocking pipe.The slump test,pressure bleeding experiment,and the compressive strength experiment it is concluded that the new material of graphite powder has improve the pumpability of concrete.When the ratio of fly ash is15%~20%,the ratio of graphite powder is 5%~10%,the workability of concrete is better,with good availability of pumps.And compared with the super-tall projects,the pumpability of concrete has better and save the cost 1.435 yuan/m3,when the proportion of fly ash is 15%,the proportion of graphite powder is 5% and the proportion of zeolite powder is 20%.And with a large number of literature and actual engineering plan is sorted out and induced,this paper has summarized and supplemented the relevant formula and requirements of pumping equipment type selection,has listed the different pumping pressure calculative method and analyzed their advantages,disadvantages and suitable conditions.The paper has also found out the formula which are suitable for the practical engineering,and putted forward the research direction of pumping pressure calculation should be considered in the two aspects of the inertia effect and yield stress of concrete.At last,the relevant technical requirements of construction control points and precautions were sorted out,which was supplemented and perfected for the "Technical regulations of concrete pumping construction",and also provided reference and reference for the similar project construction.