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陳   迎

（廣西壯族自治區(qū)港航發(fā)展中心 ，南寧 530029)

摘   要 ：為研究機制砂中石粉摻量對混凝土早期體積穩(wěn)定性的影響 ，測試了不同石粉摻量的不同強度混凝土和易性、早期收縮和抗裂性能、抗壓強度和孔隙結(jié)構(gòu)。結(jié)果表明：摻加適量石粉可有效改善機制砂混凝土拌 合物的保水性 、黏聚性和抗離析性，有利于提高機制砂混凝土的抗裂性能和抗壓強度；摻加過量石粉會增加混 凝土的需水量和早齡期收縮率，降低其抗裂性能和硬化后的強度。對于 C30 機制砂混凝土，石粉摻量可放寬至 20% ;  對于 C50 機制砂混凝土，石粉摻量應(yīng)嚴格控制在 10% 以內(nèi)。混凝土用機制砂中石粉摻量的最佳值應(yīng)結(jié)合工程環(huán)境和實際用途確定，更有利于砂資源貧乏區(qū)域的機制砂混凝土擴大化應(yīng)用。

關(guān)鍵詞：機制砂混凝土 ；石粉摻量 ；體積穩(wěn)定性 ；微觀結(jié)構(gòu)

中圖分類號：TU525            

文獻標志碼：A           

文章編號： 1005- 8249   (2025)  02- 0044- 06 

       DOI:10. 19860/j.cnki.issn1005 - 8249.2025 .02.008

 

CHEN Ying

(Port and Shipping Development Center of Guangxi Zhuang Autonomous Region ,  Nanning 530029 ,  China) 

Abstract：To study the influence of stone powder content on the early shrinkage and cracking performance of manufactured concrete, the working performance, early shrinkage, early cracking, compressive strength, and pore distribution of manufactured sand concrete with different strength and different contents were tested. The test results show that the addition of stone powder is beneficial to improve the water retention, cohesiveness, and anti-segregation performance of manufactured sand concrete but it will increase the amount of water reducing agent and early shrinkage strain of manufactured sand concrete. An appropriate amount of stone powder is beneficial to improve the crack resistance and compressive strength of manufactured sand concrete, but excessive stone powder will lead to the decrease of crack resistance and compressive strength. The stone powder content in manufactured sand can be relaxed to 20% for C30 concrete, and the content of stone powder should be controlled within 10% for the C50 concrete. The optimum value of stone powder content in manufactured sand for concrete should be determined in combination with engineering environment and practical use, which is more conducive to the expansion application of manufactured sand concrete in areas with poor sand resources.

Keywords: manufactured sand concrete; stone powder content; volume stability; microstructure

作者簡介： 陳    迎  (1975—) , 女，碩士研究生， 高級工程師 ，研究方向：混凝土材料。

收稿日期：2024 - 10 - 12