摘   要：为探索采用低掺量纤维制备超高延性混凝土（UHDC）的可行性，研究了不同长度（18、24、36 mm）的聚乙烯（PE）纤维对UHDC裂缝分布形式、拉伸应力-应变曲线、拉伸性能指标的影响。结果表明：掺不同长度PE纤维UHDC试件的裂缝宽度均小于0.20 mm，表现出显著的应变硬化和多缝开裂特征；随着PE纤维长度的增加，UHDC试件的峰值应力、极限拉伸应变、应变能均呈先增后减的趋势，初裂应力呈降低趋势；当PE纤维长度为24 mm时，UHDC试件的峰值应力、极限拉伸应变、应变能相对最优，分别为6.58 MPa、5.44%、234.53 kJ/m3。 Abstract: In order to explore the feasibility of preparing ultra-high ductile concrete(UHDC) with low content fiber, the effects of polyethylene(PE) fiber with different lengths(18, 24, 36 mm) on the crack distribution form, tensile stress-strain curve, and tensile properties indicators of UHDC were investigated. The results show that, the crack widths of UHDC specimens mixed with different lengths of PE fiber are less than 0.20 mm, and the UHDC specimens show significant strain hardening and multiple cracking characteristics. With the increase of the length of PE fiber, the peak stress, ultimate tensile strain, and strain energy of UHDC specimens show a tendency of first increasing and then decreasing, and the initial cracking stress shows a tendency of decreasing. When the length of PE fiber is 24 mm, the peak stress, ultimate tensile strain and strain energy of UHDC specimens are relatively optimal, which are 6.58 MPa, 5.44% and 234.53 kJ/m3, respectively.

张媛,曹泽召,王义超,等.低纤维掺量超高延性混凝土的拉伸性能研究[J].混凝土与水泥制品,2025(5):53-57. ZHANG Y,CAO Z Z,WANG Y C,et al.Study on tensile properties of ultra-high ductility concrete with low content fiber[J].China Concrete and Cement Products,2025(5):53-57.

摘   要: 研究了龄期、基体混凝土强度等级、界面粗糙度、界面湿润度、界面剂对改性活性粉末混凝土（MRPC）与普通混凝土（NC）界面黏结性能的影响。结果表明：MRPC-NC试件的劈裂抗拉强度随龄期的增长而增大，劈裂抗拉强度基本在7 d内发展完全；随着基体混凝土强度等级的增大，MRPC-NC试件的劈裂抗拉强度不断提升，但增幅有限；MRPC-NC试件的劈裂抗拉强度随着界面湿润度的增加而增大，其中，湿饱和状态下的界面黏结性能相对最优；不同界面处理方式对MRPC-NC试件劈裂抗拉强度的影响顺序大小为：凿毛+刻槽＞凿毛+涂抹YJ-302＞凿毛+涂抹水泥净浆＞凿毛＞光滑。 Abstract: The effects of age, strength class of matrix concrete, interfacial roughness, interfacial wetness, and interfacial agent on the interfacial adhesive properties of modified reactive powder concrete (MRPC) and normal concrete (NC) were investigated. The results show that the splitting tensile strength of MRPC-NC specimens increases with the growth of age, and the splitting tensile strength basically develops completely within 7 d. The splitting tensile strength of MRPC-NC specimens improves continuously with the increase of matrix concrete strength class, but the increase is limited. The split tensile strength of MRPC-NC specimens increased with the increase of interface wetness, in which the interface adhesion performance in the wet saturated state was relatively optimal. The magnitude of the effect of different interface treatments on the splitting tensile strength of MRPC-NC specimens is in the following order: chiseling+grooving>chiseling+brushing YJ-302>chiseling+brushing cement net mortar>chiseling>smooth.

王欣,徐昊,栾学立,等.改性RPC与NC黏结面劈裂抗拉性能试验研究[J].混凝土与水泥制品,2025(5):58-62. WANG X,XU H,LUAN X L,et al.Experimental study on splitting tensile properties of bonding surface between modified RPC and NC[J].China Concrete and Cement Products,2025(5):58-62.

摘   要：研究了冬季低温环境下，标准养护、组合养护、室外养护对超高性能混凝土（UHPC）力学性能的影响，并从微观角度分析了影响机理。结果表明：在冬季低温环境下，不同养护方式对UHPC试件3~90 d抗折强度和3~28 d抗压强度的影响顺序大小均为：标准养护＞组合养护＞室外养护，对90 d抗压强度的影响顺序大小为：标准养护＞组合养护≈室外养护；组合养护、室外养护UHPC试件的90 d抗折强度分别可达标准养护UHPC试件的89.2%、67.9%，90 d抗压强度分别可达82.7%、84.3%；与标准养护相比，室外养护UHPC试件基体内部结构较为疏松；低温环境减缓了水泥的水化进程，抑制了掺合料的火山灰活性，增大了UHPC试件基体内部孔隙率。 Abstract: The effects of standard curing, combined curing, and outdoor curing on the mechanical properties of ultra-high performance concrete(UHPC) were investigated under the low-temperature environment in winter, and the influence mechanism was analyzed from the microscopic perspective. The results show that, under the low-temperature environment in winter, the orders of effects of different curing methods on the 3~90 d flexural strength and 3~28 d compressive strength of UHPC specimens are as follows: standard curing ＞ combined curing ＞ outdoor curing, and the order of effects of different curing methods on the 90 d compressive strength of UHPC specimens is as follows: standard curing ＞ combined curing ≈ outdoor curing. The 90 d flexural strength of UHPC specimens under combined curing and outdoor curing can reach 89.2% and 67.9% of that of UHPC specimens under standard curing, and the 90 d compressive strength can reach 82.7% and 84.3%, respectively. Compared to standard curing, UHPC specimens under outdoor curing have a loose internal structure. The low-temperature environment slows down the hydration process of cement, hinders the volcanic ash activity of admixtures, and increases the internal porosity of UHPC specimen matrix. 

韩炜,王常春,范文成,等.冬期低温养护对UHPC力学性能的影响及机理分析[J].混凝土与水泥制品,2025(5):63-67. HAN W,WANG C C,FAN W C,et al.Study and mechanism analysis of the effect of low-temperature curing in winter on the mechanical properties of UHPC[J].China Concrete and Cement Products,2025(5):63-67.

摘   要：研究了碎浆和磨浆工艺参数、磨盘尺寸和形式、浆板类型对磨浆效果的影响。结果表明：适当延长碎浆搅拌时间、提高磨机功率、降低出浆流量、提高回流流量或降低入口压力，可在一定程度上改善磨浆效果；增大磨盘直径会降低磨浆效果；与弧向磨纹倾向相比，直向磨纹倾向对改善磨浆效果更有利；实际生产中，可在合理调整碎浆和磨浆工艺参数的基础上，优选磨盘、浆板类型，实现纸浆、纤维参数的稳定控制，从而使磨浆效果最大化。 Abstract: The effects of pulping and grinding process parameters, grinding disk size and form, and pulp board type on the refining effect were studied. The results show that appropriately extending the mixing time of pulping, increasing the mill power, reducing the pulping extraction flow rate, increasing the reflux flow rate, or reducing the inlet pressure can improve the refining effect to a certain extent. Increasing the diameter of the grinding disk will reduce the refining effect. Compared with the arc-shaped grinding pattern, the vertical-shaped grinding pattern is more beneficial for improving the refining effect. In actual production, based on the reasonable adjustment of pulping and grinding process parameters, the types of grinding disk and pulp board can be optimized to achieve stable control of pulp and fiber parameters, thereby maximizing the refining effect.

冯宏坚.纤维水泥板生产中纸浆和纤维参数的影响因素研究[J].混凝土与水泥制品,2025(5):68-71. FENG H J.Study on the influencing factors of pulp and fiber parameters in the production of fiber cement board[J].China Concrete and Cement Products,2025(5):68-71.