| Northwest dry cold area, large temperature difference, cold, strong radiation, drying, salt corrosion, wind and sand storms, and other bad environment and climate makes concrete structure in moisture, freeze-thaw circulation, temperature, salt corrosion, erosion and other natural factors under, accumulate over a long period, in the concrete structure easily produced cracks, erosion and other diseases. At this stage, the development of building materials industry is generally not high. Also material quality and function of materials on the market are not up to the standard, not defects is a variety of hazards, also the entire project usually cases have bearing force is too large, the construction project engineering service life is generally too short, repair costs soared, resulting in a serious waste of resources. So, taking the opportunity of starting point, in order to achieve the improvement of traditional mortar,mortar mixed with polymers can in the shortest period of time will be the building surface crack repair intact, this point to further improve the types of technical means, to safeguard,with further development can well be this technology applied to the engineering construction.In northwest dry cold area mortar construction process analysis, the selection of the three polymers: emulsified asphalt, Cr latex and acrylic emulsion as doped polymer into mortar as the dominant component, combined with dry cold area characteristics, on the selected polymer material role were rational analysis and discussion. The main object of study in the following: to add three kinds of polymer mortar, the construction effect of mortar were analyzed; the mechanical effect of hardened mortar were comparative analysis.From the final research results, compared with the ordinary mortar, polymer modified mortar has a slight decrease in flexural strength and compressive strength, and with the increase of the amount of polymer emulsion increased, the strength of the first increase and then decrease, the optimal dosage is about 15%;The mixing of polymer emulsion and admixture can also get good internal bore structure and high mechanical strength in the condition of Northwest China. This indicates that the modified mortar is more suitable for the construction of complex conditions than ordinary mortar. When the water cement ratio is fixed, the water cement ratio decreases gradually, but the initial setting time and the final setting time can be reduced and then increased, but it is not accelerated by the increasing of the ratio of polymer content. The mortar compressive strength was greatly improved by the addition of chloride latex, and the relative mortar was increased by 2.7% compared with that of 28 d. The blending of acrylic latex to the flexural strength of mortar increased significantly.When the content of 28 d was 20%, the flexural strength of the polymer was the biggest,which was 3.6% higher than that of the mortar. 90 d, the compressive strength of the mortar was increased by 9%. The relationship between the ratio of the polymer modified mortar and the age of the mortar is inversely proportional to the pressure. The age is to increase thepolymer modified sand decreases, mainly due to the compressive strength of mortar is more than the same period in the same time to increase the strength of the same period. The bond strength of mortar is proportional to the content of content, and the increase of the content of the mortar increases with the increase of the bond strength. The influence of the bond strength was the most obvious one is the 90 d, the bond strength increased by 20%. But the adhesive strength of the polymer modified mortar decreased with the age of the same age. The main reason is that the amount of acrylic acid is too much. The effect of the polymer film is not promoted by the amount of the polymer film, but also slows the hydration process of cement.Through the test data can calculate the best curing environment and the maintenance condition of the matching mechanism analysis. |
PDF Full Text Request