【摘要】：本文采用中國石油集團工程技術研究院研制的UWB-Ⅱ型抗分散劑,通過對不同配合比下水下不分散混凝土的抗分散性、流動性、水陸強度比等性能的試驗研究,分析抗分散劑、粉煤灰、用水量、砂率對水下不分散混凝土性能的影響,并配制出C35水下不分散混凝土的最優(yōu)配合比。 本文首先介紹了水下不分散混凝土的發(fā)展歷史和研究概況,對水下不分散混凝土的應用技術做了簡要的概括。然后依據(jù)《水下不分散混凝土試驗規(guī)程》,運用正交試驗研究混凝土抗分散劑、粉煤灰、水膠比以及砂率對水下不分散混凝土的流動性、抗分散性、立方體抗壓強度的影響,并經(jīng)過合理的調整,找到比較合理的配合比。 本文采用“四因素三水平”的正交試驗法,以抗分散劑、粉煤灰、水膠比、砂率為本試驗的四個因素,并以四因素三個水平組成的試驗組進行試驗。主要結論如下： 混凝土抗分散劑能保證混凝土在水中澆筑不泌水、不離析,在一定摻量范圍內(nèi)能夠顯著提高水下混凝土的強度,但對混凝土的流動性有不利影響,其流動性隨著抗分散劑摻量的增加而減小。采用中國石油集團工程技術研究院研制的UWB-Ⅱ型抗分散劑時,2.5%摻量的混凝土抗分散劑比較合理。 混凝土的水膠比是影響水下不分散混凝土流動性和強度的一個重要因素,本試驗中,水膠比為0.38時混凝土強度達到最大值,且此時水下不分散混凝土的流動性滿足要求；隨著水膠比的增大,混凝土的流動性雖然有所提高,但其強度降低的更為明顯,所以在滿足混凝土流動性的前提下,取最優(yōu)水膠比為0.38。 粉煤灰能提高水下不分散混凝土的流動性并減少混凝土拌合物流動性的經(jīng)時損失。粉煤灰還能提高水下抗分散混凝土后期強度,在20%～30%時,粉煤灰的作用效果最明顯。
[Abstract]:In this paper, UWB- type II anti-dispersing agent developed by China Petroleum Group Engineering and Technology Research Institute is used to analyze the anti-dispersing agent through the experimental study on the anti-dispersion, mobility and water-land strength ratio of non-dispersed concrete under different mix ratios. The effects of fly ash, water consumption and sand ratio on the properties of underwater non-dispersed concrete are studied, and the optimal mix proportion of C35 underwater non-dispersed concrete is prepared. In this paper, the development history and research situation of underwater non-dispersion concrete are introduced, and the application technology of underwater non-dispersion concrete is briefly summarized. Then, according to the underwater non-dispersible concrete test code, the effects of concrete anti-dispersing agent, fly ash, water-binder ratio and sand ratio on the mobility, dispersion resistance and cube compressive strength of underwater non-dispersed concrete are studied by orthogonal test. And after reasonable adjustment, find a more reasonable mix ratio. In this paper, the orthogonal test method of "four factors and three levels" is used to take the anti-dispersing agent, fly ash, water-binder ratio and sand rate as the four factors of this experiment, and the experimental group composed of four factors and three levels is used to carry out the test. The main conclusions are as follows: the anti-dispersing agent of concrete can ensure that the concrete does not secrete and do not separate in the water, and can significantly improve the strength of underwater concrete in a certain range of content, but has a negative effect on the mobility of concrete. The mobility decreases with the increase of the content of anti-dispersing agent. When the UWB- type II anti-dispersing agent developed by China Petroleum Group Engineering and Technology Research Institute is used, the 2.5% content of concrete anti-dispersing agent is more reasonable. The water-binder ratio of concrete is an important factor affecting the mobility and strength of underwater non-dispersed concrete. In this experiment, when the water-binder ratio is 0.38, the strength of concrete reaches the maximum, and the mobility of underwater non-dispersed concrete meets the requirements. With the increase of water-binder ratio, although the mobility of concrete increases, but its strength decreases more obviously, so under the premise of satisfying the mobility of concrete, the optimal water-binder ratio is 0.38. Fly ash can improve the mobility of underwater non-dispersed concrete and reduce the time loss of concrete mixture. Fly ash can also improve the later strength of underwater anti-dispersion concrete, and the effect of fly ash is the most obvious when it is 20% 鈮，

本文編號：2478950