發(fā)布時間：2018-03-04 03:16

  本文選題：聚羧酸系減水劑　切入點：消泡劑　出處：《南昌航空大學(xué)》2014年碩士論文　論文類型：學(xué)位論文

【摘要】：聚羧酸系減水劑具有摻量低、減水率高、保坍性能強等優(yōu)點，在商品混凝土生產(chǎn)中得到廣泛應(yīng)用。然而將聚羧酸系減水劑單獨與混凝土拌合時，經(jīng)常會出現(xiàn)與水泥適應(yīng)性不好的現(xiàn)象，導(dǎo)致混凝土拌合物和易性差、坍落度損失大等問題，難以滿足施工要求。因此，聚羧酸系減水劑一般需要與其他外加劑復(fù)配使用。 本文通過試驗，對聚羧酸系減水劑和其他外加劑的復(fù)配對混凝土性能的影響進行了較為系統(tǒng)的研究，并得出相應(yīng)結(jié)論。主要有： （1）聚羧酸系減水劑和不同的緩凝劑復(fù)配對混凝土拌合物凝結(jié)時間、坍落度及損失、混凝土抗壓強度的影響。隨著檸檬酸鈉摻量的增大，混凝土拌合物的凝結(jié)時間延長、混凝土抗壓強度降低，葡萄糖酸鈉摻量的增大也可以延長混凝土拌合物的凝結(jié)時間，但對混凝土28d強度影響不大。二者對混凝土均有輔助塑化作用和保坍作用。 （2）聚羧酸系減水劑和不同的引氣劑復(fù)配以及改變引氣方式對混凝土含氣量及損失、抗壓強度和抗氯離子滲透性能的影響。隨著德固賽或三萜皂甙摻量的增加，混凝土的抗壓強度降低，含氣量增大，但氣泡易聚合后逸出。與德固賽相比，三萜皂甙引氣效果更顯著。改變引氣方式后，混凝土含氣量經(jīng)時損失減小，氣泡較穩(wěn)定；德固賽摻量為0.01‰~0.04‰、三萜皂甙為0.06‰~0.10‰時，混凝土的抗氯離子滲透性能有所提高。 （3）聚羧酸系減水劑和外加劑優(yōu)化配比。通過四種復(fù)配組合的對比分析，可以得出德固賽、葡萄糖酸鈉、竹本油脂和聚羧酸系減水劑復(fù)配后與水泥適應(yīng)性較好，混凝土各方面性能最優(yōu)，且德固賽的最佳摻量為0.03‰，，葡萄糖酸鈉的最佳摻量為0.06%。 本文研究成果可以為混凝土外加劑配比設(shè)計提供參考。
[Abstract]:Polycarboxylic acid superplasticizer has been widely used in the production of commercial concrete because of its advantages of low content, high water reducing rate and strong collapsibility. However, when the polycarboxylate water reducer is mixed with concrete alone, The poor adaptability to cement often leads to poor mixing and ease of concrete, large slump loss and so on, so it is difficult to meet the construction requirements. Therefore, polycarboxylic acid series water reducers usually need to be combined with other admixtures. In this paper, the effects of polycarboxylic acid superplasticizer and other admixtures on concrete properties are studied systematically, and the corresponding conclusions are drawn. 1) the effects of polycarboxylic acid series water reducer and different retarder on the setting time, slump and loss of concrete mixture, and the compressive strength of concrete. With the increase of sodium citrate content, the setting time of concrete mixture is prolonged. The compressive strength of concrete decreases, and the increase of sodium gluconate content can also prolong the setting time of concrete mixture, but it has little effect on the strength of concrete for 28 days. Both of them have auxiliary plasticizing and collapsing effect on concrete. 2) the effects of polycarboxylic acid superplasticizer and different air entraining agent on the air content and loss, compressive strength and chloride ion permeability of concrete by changing the way of air entraining, with the increase of Degusai or triterpenoid saponins, The compressive strength of concrete decreases, the gas content increases, but the bubble is easily polymerized and escapes. Compared with Degusai, triterpenoid saponins are more effective in entraining air. After changing the way of entraining, the loss of air content in concrete decreases and the bubble is more stable. When the dosage of Degusai was 0.01 鈥

本文編號：1563893