文章信息/Info

Title:

Study on Bending Toughness and Multi-Crack Cracking Mechanism of Nano�睵article and Long-Short Fiber Co-Modified Alkali-Activated Material

文章編號:

1674-3962(2025)12-1120-08

作者:

何小軍; 高承基; 何怡媚; 李黎

1. 陜西省寶雞峽工程局，陜西 寶雞 721001 2. 西北農(nóng)林科技大學(xué)水利與建筑工程學(xué)院，陜西 楊凌 712100

Author(s):

HE Xiaojun;  GAO Chengji;  HE Yimei;  LI Li

1. Baoji Gorge Engineering Bureau, Baoji 721001, China 2. College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China

關(guān)鍵詞:

堿激發(fā)材料; 納米碳酸鈣; PP纖維; 彎曲韌性; 多縫開裂; 混雜效應(yīng)

Keywords:

alkali-activated material;  nano CaCO3;  PP fiber;  bending toughness;  multi�瞔rack opening;  hybrid effect

分類號:

TB332

DOI:

10.7502/j.issn.1674-3962.202503025

文獻(xiàn)標(biāo)志碼:

A

摘要:

為提高灌區(qū)渠道修復(fù)材料的抗變形、抗裂和抗?jié)B性能，研究了納米碳酸鈣與聚丙烯（PP）纖維混雜對堿激發(fā)材料彎曲韌性、裂縫演變及微觀機(jī)理的影響。結(jié)果表明：納米碳酸鈣（質(zhì)量分?jǐn)?shù)為1%）與長�捕蘌P纖維（0.4% 6 mm+0.8% 12 mm，體積分?jǐn)?shù)）混摻可顯著提升彎曲韌性（較對照組提高42.9倍），改性后堿激發(fā)材料達(dá)到荷載峰值后荷載下降速率減緩，載荷達(dá)峰值前呈現(xiàn)撓曲硬化行為。裂縫演變和SEM微觀分析表明，納米碳酸鈣通過增強(qiáng)纖維�不�體界面化學(xué)粘結(jié)與物理摩擦，結(jié)合纖維橋聯(lián)與拔出機(jī)制，顯著延長裂縫擴(kuò)展路徑、增加了裂縫數(shù)量，提高能量耗散，從而改善彎曲韌性�；祀s效應(yīng)分析顯示，纖維因子為387��10且納米碳酸鈣摻量為1%時，正混雜效應(yīng)最顯著（S=0.596），驗證了多尺度協(xié)同增韌機(jī)制的有效性。

Abstract:

To enhance the deformation, crack resistance and impermeability of channel repair materials in irrigation districts, the hybridization effects of nano CaCO3 and polypropylene (PP) fibers on the flexural toughness, crack evolution and micro�瞞echanism of alkali�瞐ctivated material were investigated. The results show that the hybridization of 1wt% nano CaCO3 and 0.4vol% 6 mm+0.8vol% 12 mm long-short PP fibers can significantly improve the flexural toughness (42.9 times higher than the control group). The post-peak load drop rate is slowed down, and the flexural hardening behavior is present before the peak. Crack evolution and SEM microstructure analysis indicate that nano CaCO3 significantly extends the crack propagation path, increases the number of cracks, and enhances energy dissipation by strengthening the chemical bonding and physical friction at the fiber-matrix interface, and combining the fiber bridging and pull-out mechanism, thereby improving the flexural toughness. The hybrid effect analysis shows that when the fibro factor is 387��10 and the nano CaCO3 dosage is 1wt%, the positive hybrid effect is the most significant (S=0.596), verifying the effectiveness of the multi-scale synergistic toughening mechanism.