Study On Shrinkage Cracking Effect Mechanism By Curing Technology Of Concrete Structure Wall

In recent years,the cracking of the wall is often encountered in engineering after the early wall formwork is dismantled that affect the quality of the project.In order to avoid the wall cracking caused by unreasonable maintenance way,this paper focuses on discussing the problem of early age shrinkage cracking of concrete structure wall.Systematically studies the influence mechanism of shrinkage cracking problem caused by the early curing of concrete structure wall through engineering investigation,theoretical analysis,field test.At last puts forward a simple,reasonable and effective maintenance technology of concrete structure wall.First,summarize the basic theory of concrete curing,and focus on the analysis of the basic conditions of concrete materials maintenance from the micro level,such as: temperature,humidity and so on.The influence of curing condition on the performance of concrete is analyzed,such as durability,shrinkage,strength and so on.Take the super long concrete structure as an example to study the requirements for the maintenance.In this paper,the theory of thermal stress,restraint and shrinkage cracking of super long concrete structure is discussed.In the end,the basic condition to ensure the quality of concrete is put forward.Secondly,it elaborates the general construction technology of the wall,and the wall maintenance of site conditions were analyzed.At the same time comprehensively summarizes of the existing problems of wall maintenance,such as pine,form removal time,maintenance difficulties and the poor maintenance effect.In addition,combined with the construction site of the wall maintenance conditions and the basic theory of wall maintenance,give a qualitative analysis of problems in wall maintenance,obtains the key to solve the problem.At last put forward two conditions,namely: the earliest release time,the latest release time.Third,in combination with the practical engineering,the field contrast test of wall maintenance is carried out.Research the early temperature and humidity of the concrete wall was measured by the experimental.The effects of different curing conditions to shrinkage cracking of the wall were studied.At last,put forward a more reasonable wall maintenance technology.Fourth,through the experimental simulation of the construction site of the loose wall mold of the wall,the torque of pull screw is measured and compared with the torque of the loose mode on the spot.The earliest release time of the concrete wall is obtained.At the same time,the compressive strength of the test block was measured at different time,Through analysis obtain of the earliest release time corresponding to the concrete strength.At last,put forward the standard of loose template technology which reduces the template constraint so that avoid shrinkage and cracking in the early stage of the wall.At last,influence of temperature and humidity change on shrinkage cracking of wall in consideration of curing process,the crack control suggestions of the concrete structure wall during construction are put forward,So as to guide the engineering practice.