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張興龍

 

（首都醫科大學附屬北京中醫醫院 ，北京 100010)

摘   要 ：為研究高摻量粉煤灰混凝土力學性能，制備了摻 40% 、50% 、60% 、70% 不同比例粉煤灰及鋼纖  維 0. 25% 、0. 50% 、0. 75% 、1% （體積分數） 的混凝土試件，并將其置于模擬環境條件中進行試驗。通過測試  試件的抗壓強度、劈裂抗拉強度 、干燥收縮率及微觀結構，分析高摻量粉煤灰混凝土的力學性能。結果表明： 當粉煤灰摻量在 40%~ 50% 時，混凝土抗壓強度下降最為明顯；當鋼纖維體積分數摻量為 1% 時，劈裂抗拉強度  較未摻鋼纖維混凝土增長 24. 4% ,  抗折強度達到最大值 6. 2 MPa ,  較原始強度提高了29. 2% ;  混凝土的干燥收  縮率隨著粉煤灰摻量的增加呈現出先降低后升高的趨勢， 當摻量增加至 70% 時，收縮率較基準混凝土降低了12. 22% ,  同時混凝土的孔隙率略有回升，約為 8% ;  適當比例的粉煤灰和鋼纖維摻入能夠顯著提升混凝土的抗拉強度、抗折強度，并優化其干燥收縮性能和孔隙結構，增強混凝土的力學性和致密性。

關鍵詞：高摻量 ；粉煤灰 ；混凝土 ；鋼纖維 ；力學性能

中圖分類號：TU528 . 01            

文獻標志碼：A            

文章編號： 1005- 8249  (2025)  02- 0049- 05

DOI:10. 19860/j.cnki.issn1005 - 8249.2025 .02.009

 

ZHANG Xinglong

(Beijing Hospital of Traditional Chinese Medicine ,  Capital Medical University ,  Beijing 100010 ,  China) 

Abstract: To study the mechanical properties of high content fly ash concrete, concrete specimens containing different proportions of fly ash (40%, 50%, 60%, 70%) and steel fibers (volume fractions of 0.25%, 0.50%, 0.75%, 1.00%) were prepared and tested under simulated environmental conditions. Analyze the mechanical properties of high content fly ash concrete by testing the compressive strength, splitting tensile strength, drying shrinkage rate, and microstructure of the specimens. The results show that the compressive strength of concrete decreases most significantly when the fly ash content is between 40% and 50%; When the volume fraction of steel fibers increases from 0% to 1.00%, the increase in splitting tensile strength reaches 24.4%, and the maximum flexural strength reaches 6.2 MPa, an increase of 29.2% compared to the original strength; The drying shrinkage rate of concrete shows a trend of first decreasing and then increasing with the increase of fly ash content. When the content increases to 70%, the shrinkage rate decreases by 12.22% compared to the benchmark concrete, and the porosity of the concrete slightly increases to about 8%. Based on the above results, it can be concluded that the appropriate proportion of fly ash and steel fibers can significantly improve the tensile strength and flexural strength of concrete, optimize its drying shrinkage performance and pore structure, thereby enhancing the mechanical properties and compactness of  concrete.

Key words: high admixture; fly ash; concrete; steel fiber; mechanical properties

作者簡介： 張興龍  (1981 —) ,  男 ，本科 ，工程師 ，研究方向：建筑工程技術。

收稿日期：2024-10- 09