低热硅酸盐水泥道路混凝土性能的研究

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外文翻译--低热硅酸盐水泥混凝土的抗裂性能

外文翻译Anti-Crack Performance of Low-HeatPortland Cement ConcreteAbstract: The properties of low-heat Portland cement concrete(LHC) were studied in detail. The experimental results show that the LHC concrete has characteristics of a higher physical mechanical behavior, deformation and durability. Compared with moderate-heat Portland cement(MHC), the average hydration heat of LHC concrete is reduced by about 17.5%. Under same mixing proportion, the adiabatic temperature rise of LHC concrete was reduced by 2 ℃-3℃,and the limits tension of LHC concrete was increased by 10×10-6-15×10-6than that of MHC. Moreover, it is indicated that LHC concrete has a better anti-crack behavior than MHC concrete. Key words: low-heat portland cement; mass concrete; high crack resistance; moderate-heat portland cement1 IntroductionThe investigation on crack of mass concrete is a hot problem to which attention has been paid for a long time. The cracks of the concrete are formed by multi-factors, but they are mainly caused by thermal displacements in mass concrete[1-3]. So the key technology on mass concrete is how to reduce thermal displacements and enhance the crack resistance of concrete.As well known, the hydration heat of bonding materials is the main reason that results in the temperature difference between outside and inside of mass concrete[4,5]. In order to reduce the inner temperature of hydroelectric concrete, several methods have been proposed in mix proportion design. These include using moderate-heat portland cement (MHC), reducing the content of cement, and increasing the Portland cement (OPC), MHC has advantages such as low heat of hydration, high growth rate of long-term strength, etc[6,7]. So it is more reasonable to use MHC in application of mass concrete.Low-heat portland cement (LHC), namely highbelite cement is currently attracting a great deal of interest worldwide. This is largely due to its lower energy consumption and CO2 emission in manufacture than conventional Portland cements.LHC has a lot of noticeable properties, such as low heat of hydration excellent durability, etc, so the further study continues to be important[8-10]. The long-term strength of C2S can approach to or even exceed that of C3S[11]. In addition, C2S has a series of characteristics superior to C3S. These include the low content of CaO, low hydration heat, good toughness, compact hydration products, excellent resistances to chemical corrosion, little dry shrinkage, etc[12,13].For hydroelectric concrete , the design requirements have some characteristics, such as long design age, low design strength, low hydration temperature rise, and low temperature gradient[14]. All these requirements agree with the characteristics of LHC. Furthermore, LHC has a high hydration activity at later ages, the effect of which can improve the inner micro-crack. Based on above-mentioned analyses, the properties of low-heat Portland cement concrete were studied in detail in this paper. Compared with the moderate-heat Portland cement (MHC) concrete, the anti-crack behavior of LHC concrete was analyzed.2 ExperimentalMHC was produced in Gezhouba Holding Company Cement Plant, China; and LHC was produced in Hunan Shimen Special Cement Co. Ltd., China. The chemical compositions and mineral compositions of cement are listed in Table 1 and Table 2 respectively, and the physical and mechanical properties of cement are listed in Table 3.In spite of a little difference in chemical compositions, there is an obvious dissimilarity between the mineral component of LHC and that of MHC because of the different burning schedule. The C3S (Alite) content of MHC is higher than that of LHC, and the C2S (Belite) content of LHC is higher than that of MHC. Alite is formed at temperatures of about 1 450 ℃, while Belite is formed at around 1 200 ℃. Therefore, LHC can be manufactured at lower kiln temperatures than MHC. And the amount of energy theoretically required to manufacture LHC is lower than that of MHC.Belite hydrates comparatively slowly, and the early compressive strengths of pastes, mortars, and concretes containing LHC are generally lower as a result. The long-term strength and durability of concrete made from LHC can potentially exceed those of MHC. The results from Table 3 show that the early strength of LHC pastes is lower than that of MHC pastes, and that the strength growth rate of LHC is higher than that of MHC.The hydration heat of bonding materials was tested. Class I fly ash of bonding materials came from Shandong Zhouxian Power Plant, China. The experimental results shown in Table 4 indicate that the hydration heat of LHC is much lower than that of MHC. The 1-day, 3-day and 7-day hydration heat of LHC without fly ash is 143 kJ/kg, 205 kJ/kg, 227 kJ/kg, respectively. The 1-day, 3-day and 7-day hydration heat of MHC without fly ash is 179 kJ/kg, 239 kJ/kg, 278 kJ/kg, respectively. Compared with MHC, the average hydration heat of LHC concrete is reduced by about 17.5%. Obviously, low hydration is of advantage to abate the pressure to temperature control, and to reduce the crack probability due to the temperature gradients. The adiabatic temperature of LHC concrete and MHC concrete was tested. As a result, the adiabatic temperature rise of LHC concrete is lower than that of MHC concrete and the different value ranges from 2 ℃to 3 ℃in general.After adding fly ash, all specimens show a lower hydration heat, and it decreases with increasing fly ash content. For MHC with 30% fly ash, the 1 d, 3 d, 7d accumulative hydration heat is reduced by 14.5%, 20.5%, 21.9%, respectively; and for LHC with 30% fly ash, the 1 d, 3 d, 7 d accumulative hydration heat is reduced by 21.7%, 26.3%, 23.3%, respectively. Obviously, the effect of fly ash on the hydration heat of LHC is more than that of MHC. It is well known that the fly ash activation could be activated by Ca(OH)2. LHC has a lower content of C3S and a higher content of C2S than MHC, so the Ca(OH)2, namely the exciter content in hydration products of LHC pastes is lower. Decreasing the hydration activation of fly ash reduces the hydration heat of bonding materials.3 Results and DiscussionIn this experiment, ZB-1A type retarding superplasticizer and DH9 air-entraining agent were used. The dosage of ZB-1 was 0.7% by the weight of the blending, and the dosage of DH9 was adjusted to give an air-containing of 4.5% to 6.0%. The parameters that affected the dosage included the composition and the fineness of thecement used, and whether the fly ash was used. Four gradations of aggregate were used, 120 mm-80 mm: 80 mm-40 mm: 40 mm-20 mm: 20 mm-5 mm=30:30:20:20.The term water-to-cementitious was used instead of water-to-cement, and the water-to-cementitious ratio was maintained at 0.50 for all the blending. The slump of concrete was maintained at about 40 mm, and the air content was maintained at about 5.0% in the experimental. After being demoulded, all the specimens were in a standard curing chamber. The mix proportion parameter of concrete is listed in Table 5.3.1 Physical and mechanical propertiesThe physical and mechanical properties include strength, elastic modulus, limits tension, and so on. The results of strength shown in Table 6 indicate the early strength (7 d curing ages) of LHC (odd samples) concrete increases slowly. The ratio between 7 d compressive strength and 28 d compressive strength of LHC concrete is about 0.4, while for MHC concrete the ratio is about 0.6. Compared with MHC concrete, the growth rate of strength of LHC concrete becomes faster after 7 d curing ages. The compressive strength for 28 d, 90 d, 180 d curing ages of LHC concrete containing 20% of fly ash is 30.2 MPa, 43.8 MPa, 48.5 MPa, respectively, while that of MHC concrete containing 20% of fly ash is 28.3 MPa, 35.6 MPa, 39.8 MPa, respectively. The content of C2S in LHC is higher than that in MHC, which results in the above-mentioned difference.Table 6 shows that the strength growth rate of concrete made with fly ash blended cements is higher than that of blank specimens; the more the dosage of fly ash, the higher the growth rate. Fly ash has a glassy nature, which can react with Ca(OH)2. Since Ca(OH)2 is a hydration product of cement, the reaction between fly ash and Ca(OH)2, called “secondary hydration”, will happen at latish ages. The magnitude of Ca(OH)2 is affected by some factors, such as the water-to-cementitious,the dosage of cement.The elastic modulus and the limits tension of concrete are given in Table 7. Under same mixing proportion, the elastic modulus of LHC concrete is approximately equal to that of MHC; the 28-day limits tension of LHC concrete is increased by 10×10-6 to 15 ×10-6 than that of MHC, and the 90-day limits tension of LHC concrete is increased by 12×10-6 than that of MHC concrete. The above results show that the use of LHC improves the limits tension of concrete. Increasing the limits tension of concrete will be benefit to the crack resistance of concrete.3.2 Deformation characteristicsDeformation characteristics of concrete include drying shrinkage, autogenous deformation, creep, etc. The drying shrinkage of concrete is shown in Fig.1. The drying shrinkage increases with age. At early ages a up to 90 days, all the LHCconcrete specimens show a lower drying shrinkage; and it decreases with increasing the fly ash content. When containing 30% of fly ash, the drying shrinkage of LHC concrete is 363 ×10-6 at 90 days, while for MHC concrete the value is 408×10-6. As a result, the volume stability of LHC concrete is better than that of MHC concrete in drying environment.Experiment results of autogenous deformation of concrete are given in Fig.2. There is an obvious difference between the development of autogenous deformation of LHC concrete and that of MHC concrete. The autogenous deformation of LHC concrete has an expansive tendency. At early ages up to 14 days, the autogenous deformation of pure LHC samples increases with age, and the 14-day value reaches a peak of 20×10-6. The autogenous deformation of pure LHC samples decreases with age at 14 days to 90 days, and the 90-day value is 10×10-6. After adding 30% of fly ash, the autogenous deformation of LHC concrete increases with age, and the 90-day value is 61×10-6. The autogenous deformation of MHC concrete has a tendency to shrink, especially without fly ash.3.3. DurabilityThe durability of concrete is evaluated by antipenetrability grade and frost-resistant level. Under the pressure of 1.2 MPa, the permeability height of pure LHC samples is 3.1 cm, while that of pure MHC samples is 2.0 cm. The test dataindicate that the LHC concrete has an excellent performance in anti-penetrability, as well as MHC concrete. The permeability of concrete increases somewhat with addition of fly ash. At the end of the 250 freezing and thawing cycling, there is a little difference in both mass and resonant frequency. Both LHC concrete and MHC concrete show an excellent frost-resistant behavior. The results of this work confirm that LHC concrete systems have an adequate anti-penetrability and frost-resistance to adapting design requirement.3.4 Analysis of crack resistanceIn order to control the crack phenomena, it is important to accurately evaluate the anti-crack behavior.As well known, concrete is a kind of typical brittle materials, and its brittleness is associated with the anti-crack behavior[15]. The brittleness is measured by the ratio of tension strength to compressive strength. With the increase of the ratio, concrete has a less brittleness, better crack resistance and toughness. It is indicated from the experiment results shown in Table 6 that the ratio of LHC concrete at all stages of hydration is higher than that of MHC concrete, which shows that LHC concrete has a better anti-crack behavior.In the crack control and design of hydroelectric mass concrete, the original evaluation of crack resistance behavior of concrete is using the utmost tensile strength which is shown in the following expression of Eq.1.σ=εP E (1)where, εP is the limits tension of concrete, and E is the elastic modulus of tension, which is assumed to be equal to the elastic modulus of compression[16].It is indicated from the calculation results shown in Table 8 that the utmost tensile strength of LHC concrete at all stages of hydration is higher than that of MHC cncrete.The research on materials crack resistance which is the basis for esign, construction and the choice of raw materials, has been popular in today’s world. Through a great deal of research, it is widely thought that concrete with a better crack resistance has a higher tension strength and limits tension, lower elastic odulus and adiabatic temperature rise and better volume stability[17,18].Based on above-mentioned results, the LHC concrete has a higher tension strength and limits tension, lower elastic modulus and adiabatic temperature rise, and lower drying shrinkage than MHC concrete. Compared with MHC concrete, the autogenous deformation of LHC concrete has an expansive tendency. Although the early strength of LHC concrete is lower than that of MHC concrete, its later strength has approached to or even exceed that of MHC concrete.4 Conclusionsa) The early compressive strength (7 d curing ages) of LHC is lower, but its later strength (28 d, 90 d curing ages) has approached to or even exceed that of MHC.b) Compared with MHC, the average hydration heat of LHC concrete is reduced by about 17.5%.c) Under the same mixing proportion, the elastic modulus of LHC concrete is approximately equal to that of MHC, and the limits tension of LHC concrete is increased by 10×10-6-15×10-6 than that of MHC.d) The drying shrinkage of LHC concrete is obviously smaller than that of MHC concrete, and the autogenous deformation of LHC concrete has a tendency to expand.e ) The LHC concrete has a better anti-penetrability and frost resistance, as well as the MHC concrete.f) At all stages of hydration, the anti-crack strength of LHC concrete is higher than that of MHC concrete, and the former has a higher ratio of tension strength to compressive strength.References[1] C X Yu, Z Kong. Research on the Causes of Cracks in Mass Concrete and Control Measures [J]. Low Temperature Architecture Technology (China), 2005 (5): 112-113 [2] A A Almusallam, M Maslehuddin. Effect of Mix Proportions on Plastic Shrinkage Cracking of Concrete in Hot Environments[J].Construction and Building Materials, 1998 (12): 353-358[3] Xu Jing’an, An Zhiwen. Countermeasure of Temperature Crack of Mass Concrete[J]. Journal of Hebie Institute of Architectural Engineering, 2005,23(3):36-40[4] Peng Weibing, Ren Aizhu. Effects and Evaluation on Cracking of Concrete Incorporating Supplementary Cementitious Materials[J]. Concrete (China), 2005 (6): 50-64[5] Xiao Reimin, Zhang Xiong. Effect of Binder on Drying Shrinkage of Concrete [J].China Concrete and Cement Products, 2002 (5): 11-13[6] Ye Qing, Chen Xin. Research on the Expansive Mechanism of Moderate Heat Portland Cement with Slight Expansion [J].Journal of the Chinese Ceramic Society, 2000, 128 (4):335-347[7] Shi Xun. Application of Slight Expansion Cement on Concrete of Stage II Works of the Three Gorges Project [J]. Cement (China). 2002 (5): 12-14[8] Nagaokas, Mizukosui M. Property of Concrete Using Beliterich Cement and Ternary Blended Cement [J]. Journal of the Society of Materials Science, Japan, 1994, 43 (491): 488-492[9] Ge Juncai. Technology Progress of Cement and Concrete [M]. Beijing: China Building Material Industry Press , 1993:275-276[10] Metha P K. Investigation on Energy-saving Cement[J]. World Cement Technology, 1980, 1(3): 166-177[11] Taylor. Cement Chemistry[M]. London: Academic Press, 1990:142-152[12] Sui Tongba, Liu Kezhong. A Study on Properties of High Belite Cement [J]. Journal of the Chinese Ceramic Society, 1999, 127 (4): 488-492[13] Yang Nanru, Zhong Baixi. Study on Active -C2S[C]. Symposium onCement,1983:180-185[14] Yang Huanquan, Li Wenwei. Research and Application of Hydroelectric Concrete[M]. Beijing, China Water Power Press,2004:393-394[15] E Ringot, A Bascoul. About the Analysis of Micro-cracking in Concrete[J]. Cement and Concrete Composites, 2001 (23):261-266[16] Li Guangwei. Assessment for Anti-Crack Performance of Concrete [J]. Advances in Science and Technology of Water Resources (China), 2001, 21 (2): 33-36[17] Liu Shuhua, Fang Kunhe. Summarization of Norm of Crack Resistance of Concrete[J]. Highway (China), 2004 (4): e[J] 105-107低热硅酸盐水泥混凝土的抗裂性能摘要：低热硅酸盐水泥混凝土（LHC）的特性详细地被研究。

低热硅酸盐水泥在闸墩混凝土中的应用研究

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低热硅酸盐水泥在闸墩混凝土中的应用研究

道路硅酸盐水泥在冷区道路建设中的适用性研究

道路硅酸盐水泥在冷区道路建设中的适用性研究摘要：道路硅酸盐水泥拥有较高的力学性能和抗冻性，使其在冷区道路建设中具有广阔的应用前景。

本文通过研究道路硅酸盐水泥在冷区道路建设中的适用性，包括其物理性能、低温冻融性能、破坏机理等方面。

研究表明，道路硅酸盐水泥在冷区道路建设中表现出较好的适应性和稳定性，能够满足冷区道路对于冻融循环和重载交通的要求。

1. 引言道路建设是城市基础设施建设的重要组成部分，对于城市的发展和人民生活具有重要影响。

在寒冷地区，气候条件严酷，道路建设面临着一系列的挑战，如低温冻融、重载交通等。

传统的水泥路面在冷区存在着耐久性差、易龟裂等问题。

因此，研究新型材料在冷区道路建设中的应用具有重要意义。

2. 道路硅酸盐水泥的物理性能道路硅酸盐水泥是一种由硅酸盐矿物和水泥基质组成的材料。

相较于传统的水泥材料，道路硅酸盐水泥具有较高的抗压强度、耐久性和抗冻性能。

其物理性质的研究表明，该材料具有合适的柔性和刚性，使其适用于在冷区建设道路。

3. 低温冻融性能研究在冰冻的气候条件下，道路材料的抗冻性能成为评估其适用性的重要指标之一。

道路硅酸盐水泥在低温冻融循环下的性能研究表明，其抗冻融性能较好，具有较高的抗裂性和抗龟裂性。

这主要归因于硅酸盐矿物中的化学和物理反应，使得该材料在低温环境下能够保持较高的稳定性。

4. 破坏机理研究通过对道路硅酸盐水泥的破坏机理研究，可以更好地了解其在冷区道路建设中的适用性。

实验表明，道路硅酸盐水泥在受到冻融循环或重载交通作用下，其破坏机理主要包括冻融损伤、裂缝扩展等。

然而，与传统水泥材料相比，道路硅酸盐水泥具有更高的抗裂性和抗龟裂性，能够有效缓解这些破坏机制带来的影响。

5. 道路硅酸盐水泥的应用案例通过分析道路硅酸盐水泥在冷区道路建设中的应用案例，可以更好地评估其适用性和可行性。

近年来，一些地区纷纷采用道路硅酸盐水泥进行冷区道路改造，取得了显著的改善效果。

这些案例证明，道路硅酸盐水泥能够满足冷区道路对于抗冻融和承载能力的要求。

低热硅酸盐水泥

详细描述
在道路工程中，低热硅酸盐水泥具有良好的适用性，能够显著提高路面的强度、耐磨性和抗滑性。相较于普通水泥，低热硅酸盐水泥具有较低的水化热和早期的强度，能够更好地适应道路工程的施工环境。使用低热硅酸盐水泥可以显著提高路面的使用寿命，降低维护成本，具有良好的经济效益和社会效益。
研究三
要点一
低热硅酸盐水泥在早期阶段具有较高的强度，能够满足快速施工的需求。
低热硅酸盐水泥具有良好的抗冻性，能够在寒冷的冬季施工和使用。
低热硅酸盐水泥的应用范围
大型桥梁
低热硅酸盐水泥在大型桥梁建设中得到广泛应用，能够满足桥梁的强度要求和耐久性需求。
海洋工程
海洋工程中需要使用具有抗腐蚀性的材料，低热硅酸盐水泥具有良好的耐腐蚀性，适用于海洋工程建设。
总结词
低热硅酸盐水泥在桥梁工程中的优势、应用范围和效果。
要点二
详细描述
在桥梁工程中，低热硅酸盐水泥具有显著的优势。其较低的水化热和早期的强度能够提高桥梁的承载能力和耐久性，同时避免因温度变化而产生的裂缝问题。此外，低热硅酸盐水泥还具有优良的抗渗性和耐腐蚀性，能够满足桥梁工程对于高性能建筑材料的需求。该水泥在桥梁工程的上部结构、下部结构和桥面铺装等部位均有广泛的应用。
低热硅酸盐水泥具有良好的耐水性，能够长时间承受水的浸泡和冲刷，适用于水利工程中各种水工结构的建设。
强度高
在水利工程中，低热硅酸盐水泥的高强度可以提高水工结构的承载能力和稳定性。
抗冻性好
低热硅酸盐水泥的抗冻性好，能够在寒冷气候条件下保持稳定的性能。
05
低热硅酸盐水泥的未来发展与研究方向
Chapter
研究四
总结词

低热硅酸盐水泥在海工混凝土中的应用研究

低热硅酸盐水泥在海工混凝土中的应用研究随着海洋工程建设技术的发展,各类大型海洋工程不断兴建,大体积混凝土在工程建设中的应用也日益增多,裂缝控制是大体积混凝土施工中的关键问题,结构开裂会对海工大体积混凝土的耐久性产生不利影响。

因此,在海工大体积混凝土中使用低水化热的胶凝材料,是控制混凝土结构开裂、保障结构耐久性的思路之一。

相比于普通的硅酸盐水泥,低热硅酸盐水泥(Low-heat Portland Cemen)具有早期水化热低,后期强度发展好的特点,在海洋工程建设具有广阔的应用前景。

本文在研究了PLH材料特性的基础上,分析了不同PLH胶凝材料体系的凝结硬化性能,并进一步研究了粉煤灰、矿粉对混凝土的工作性、力学性、耐久性、干燥收缩的影响,提出了采用粉煤灰、矿粉等掺合料配制高性能海工PLH混凝土的技术,最后结合开裂风险进行模拟计算与评估。

主要研究内容和结果如下:研究了粉煤灰、矿粉对低热硅酸盐水泥浆体流变性能、水化热、强度以及凝结硬化过程的影响。

结果表明:低热硅酸盐水泥浆体属于B-H流体,随着剪切速率的提高,水泥浆体出现剪切稀化特征;粉煤灰和矿粉的掺入不改变浆体的流体模型,同时随矿物掺合料掺量的增加塑性粘度增大、屈服应力降低。

低热硅酸盐水泥较普通硅酸水泥出现水化温度峰值较慢,粉煤灰和矿粉的掺入均能降低低热硅酸盐水泥胶材体系各阶段水化放热速率和放热量,粉煤灰更加显著。

研究了低热硅酸盐水泥混凝土的工作性能、力学性能、耐久性能以及体积稳定性,并同时研究了矿粉和粉煤灰对混凝土各项性能的影响,试验结果表明:PLH混凝土和易性良好,包裹性强;与同等级的普通混凝土(PO)相比,低热硅酸盐混凝土的早期强度(7d)偏低,但随着龄期的增长,强度不断提高,当养护龄期达56d、90d时,PLH的抗压强度比PO增长了103.7%、116.4%;单掺粉煤灰和矿粉时,早期强度较低,但后期强度增幅大;当10%粉煤灰+20%矿粉复掺时,混凝土工作性能和强度都得到了改善;PLH混凝土在早期氯离子扩散系数高于PO混凝土,但随着养护龄期增长,其氯离子扩散系数逐渐减小并低于PO混凝土;混凝土中掺入一定量的粉煤灰和矿粉时,可进一步降低混凝土氯离子扩散,后期效果显著;粉煤灰和矿粉的掺入均降低了混凝土各龄期的干缩率;当粉煤灰和矿粉复掺时,混凝土孔结构得到细化,硬化混凝土的密实度提高。

低热硅酸盐水泥特点及用途

低热硅酸盐水泥特点及用途特点：1.低热释放：低热硅酸盐水泥在水泥水化过程中产生的热量较少，因此可以避免由于高热释放引起的温度升高和应力产生。

这对于大体积的混凝土结构非常重要，可以减少裂缝和变形的产生，提高结构的稳定性和耐久性。

2.高耐久性：低热硅酸盐水泥具有较高的抗冻融性能和抗硫酸盐侵蚀性能，可以应对恶劣的环境条件。

此外，低热硅酸盐水泥还具有优异的化学稳定性和抗化学腐蚀性能，可以延长混凝土结构的使用寿命。

3.硬化特性良好：低热硅酸盐水泥的硬化特性与普通硅酸盐水泥相比更为出色，可以提高混凝土结构的强度和耐久性。

它具有较高的早期强度发展速度和较低的收缩性能，可以提高混凝土结构的施工效率和质量。

用途：1.大体积混凝土结构：由于低热硅酸盐水泥具有低热释放特点，因此它特别适合用于大体积混凝土结构的施工，如大坝、水库、桥梁和核电站等。

它可以有效地减少由于热应力和温度变化引起的结构损坏，提高结构的稳定性和耐久性。

2.高性能混凝土：低热硅酸盐水泥可以用于生产高性能混凝土，包括高强度混凝土、高耐久性混凝土和自密实混凝土等。

这些混凝土常用于承受高荷载和恶劣环境条件的结构中，如大楼、桥梁、隧道和海洋工程等。

3.特殊工程：低热硅酸盐水泥也适用于一些特殊工程，如耐火材料、化学防腐涂层和地下隧道等。

通过使用低热硅酸盐水泥，可以提高这些特殊结构的耐火性能、化学稳定性和耐久性。

同时，低热硅酸盐水泥也可以用于修补和加固老化混凝土结构，提高其使用寿命。

综上所述，低热硅酸盐水泥具有低热释放和高耐久性的特点，适用于大体积混凝土结构、高性能混凝土和特殊工程等领域的应用。

通过使用低热硅酸盐水泥，可以提高结构的稳定性、耐久性和使用寿命，减少结构的损坏和维修成本。

混凝土中硅酸盐水泥的性能研究

混凝土中硅酸盐水泥的性能研究一、前言混凝土是建筑工程中使用量最大的材料之一，而硅酸盐水泥是混凝土中常用的一种水泥。

硅酸盐水泥的性能对混凝土的性能具有重要影响，因此对硅酸盐水泥的性能进行研究具有重要意义。

本文将从硅酸盐水泥的物理性能、化学性能、力学性能等方面对硅酸盐水泥进行深入研究，以期为混凝土工程提供参考。

二、硅酸盐水泥的物理性能1.密度硅酸盐水泥的密度一般在2.8-3.1g/cm³之间，比普通水泥的密度要小，这也为混凝土的轻量化提供了一定的可能性。

2.热膨胀系数硅酸盐水泥的热膨胀系数一般比普通水泥要小，这意味着硅酸盐水泥在高温环境下的性能更加稳定。

3.吸水率硅酸盐水泥的吸水率一般比普通水泥要小，这也意味着硅酸盐水泥在潮湿环境下的性能更加稳定。

三、硅酸盐水泥的化学性能1.水化反应硅酸盐水泥的水化反应是一种酸碱中和反应，主要反应产物是硅酸盐胶体和水合钙硅石。

这些产物能够填充混凝土中的孔隙，从而提高混凝土的密实度和强度。

2.化学成分硅酸盐水泥的主要化学成分是硅酸盐熟料和石膏，其中硅酸盐熟料的化学成分包括SiO2、CaO、MgO等。

这些化学成分的含量和比例对硅酸盐水泥的性能有重要影响。

3.抗硫酸盐侵蚀性能硅酸盐水泥具有较好的抗硫酸盐侵蚀性能，这是由于硅酸盐水泥中的硅酸盐胶体能够填充混凝土中的孔隙，从而减少硫酸盐侵蚀的机会。

四、硅酸盐水泥的力学性能1.强度硅酸盐水泥的强度一般比普通水泥要高，这是由于硅酸盐水泥中的硅酸盐胶体能够填充混凝土中的孔隙，从而提高混凝土的密实度和强度。

2.抗裂性能硅酸盐水泥具有较好的抗裂性能，这是由于硅酸盐水泥中的硅酸盐胶体能够填充混凝土中的孔隙，从而减少混凝土中的裂缝。

3.耐久性硅酸盐水泥具有良好的耐久性，这是由于硅酸盐水泥中的硅酸盐胶体能够填充混凝土中的孔隙，从而减少混凝土中的孔隙和裂缝，从而提高混凝土的耐久性。

五、结论通过对硅酸盐水泥的物理性能、化学性能、力学性能等方面的研究，可以得出如下结论：硅酸盐水泥具有较低的密度、较小的热膨胀系数和吸水率，这意味着硅酸盐水泥在高温和潮湿环境下的性能更加稳定。

低热硅酸盐水泥改善大体积混凝土抗裂性能研究

金属的体积大得多，铁锈体积膨胀，对周围混凝土产生挤压，使混凝土胀裂。（）有的混凝土虽然设计抗裂强度高，由于原８但
超出混凝土的抗裂能力时，就会出现裂缝。（）混凝土塑性塌落引起的裂缝。２
１大体积混凝土出现裂缝的原因及处理措施
１１出现裂缝的原因。
（）温度应力产生的裂缝。混凝土在硬化期间经１
（）当结构的基础出现不均匀沉陷，有可能产６就
生裂缝，随着沉陷的进一步发展，裂缝会进一步扩大。
第４卷第ｌｌ８期２０１０年９月文章编号：０１— １９２１）８— ０３— ３１０４７（００１０７０
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Ｖｏ．１４１．Ｎｏ．８１Ｓｐ．，ｅ２００１
（）混凝土加水拌和后，泥中的碱性物质与骨３水料中活性氧化硅等起反应，出的胶状碱一硅胶从周析围介质中吸水膨涨，体积增大３倍，而使混凝土涨裂从产生裂缝。
复杂、资大、投一旦发生质量问题，果严重。而目前后大体积混凝土由于施工中的各种原因易产生裂缝，严重危害工程质量，大体积混凝土施工的技术难点。是本文结合四川大渡河深溪沟水电站工程，大体就
收稿日期：００— ７— ０２１０３

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低热硅酸盐水泥道路混凝土性能的研究
摘要：本文把市面上两种普通水泥与低热硅酸盐水泥在同样的测试条件之下，开展了水泥抗冲击性能、胶砂干缩性能与混凝土耐磨性能三个方面的试验。

依照测试结果，分析了这三种硅酸盐水泥对混凝土性能与胶砂具体有什么影响，且利用对低热硅酸盐水泥胶砂性能方面的研究，探究低热硅酸盐水泥对道路混凝土性能的影响程度。

关键词：硅酸盐水泥；低热；道路混凝土；性能
中图分类号：tu37 文献标识码：a 文章编号：
近些年，我们国家经济得到了飞速的发展，道路建设也随之迎来了其极好的发展机遇，据有效数据显示，到2013年底全国混凝土道路建设预计可以超过250万千米。

所以，为了提高道路建设的质量，从混凝土道路的主要胶凝材料——水泥方面着手研究，已经成为当前研究的主要方向。

低热硅酸盐水泥由于其具有较为优良的性能，已经被我们国家列入“九五”国家重点科技攻关计划的重点项目。

但是截止至2012
年12月，相对来说对这个项目的研究总数较少，且范围不够宽泛，在实际施工项目的应用也比较窄，仅限于大坝混凝土方面。

为了可以扩大低热硅酸盐水泥在实际施工项目中的应用范围，本文结合这种水泥的物理性能，尝试将它应用于道路混凝土方面，并采取试验手段把它与市面上常见的两种通用水泥进行测试评估，且利用对低
热硅酸盐水泥胶砂性能方面的研究，探究低热硅酸盐水泥对道路混凝土性能的影响程度。

一、测试材料与测试方法
1.测试材料
低热硅酸水泥选择的是由四川嘉华水泥厂的产品，另外两个通用水泥则选择的是广西某两个大型水泥厂生产的p·o42.5r硅酸盐水泥，这两个水泥产的生产方法都是采用干法制作。

分别对这三种水泥进行编号，c3为低热硅酸水泥，c1、 c2则分别为两种普通水泥，与之相对应的混凝土或胶砂分别是1、2、3号。

从下面两个表中可以了解到三种型号水泥对应的熟料化学成分及各自的物理性能。

三种水泥的物理性能
三种水泥熟料的化学成分和矿物组成
2.测试设备及测试方法
①依据相关规范进行水泥胶砂干缩测试，因为现今我们国家对于水泥胶砂抗冲击性能的测试还没有出台相应的标准，结合实际状况，选取落锤重力测试手段。

测试设备是落锤重力实验机，待测的混凝土构件的规格为100mm×100mm×50mm，该设备的锤头重量为3千克，将锤头升至30厘米的高度连续冲击待测混凝土构件，直到待测混凝土构件出现结构性的开裂。

测试结果以每个小组6个待测混凝土构件的平均冲击次数为宜。

②依据相关规范进行混凝土耐磨测试。

测试设备选择的是混凝土滚珠耐磨试验机，并于五千转时的磨头对待测混凝土构件进行磨损，测量磨损的深度作为待测混凝土构件的耐磨度，利用耐磨度这个数值来评估混凝土的耐磨性能。

二、测试结果与讨论
1.混凝土干缩性能
影响混凝土干缩性能主要因素是水泥砂浆，粗集料对混凝土干缩性能方面的影响非常小，所以在测试的时候单单开展水泥胶砂干缩测试，并以这个测试结果进行混凝土干缩性能的评估。

三个型号水泥胶砂在各个龄期的干缩数据见下图。

在上图中，较小浅颜色的虚线表示的是低热硅酸盐水泥，较大虚线与实线分别表示c1、c2。

上图表示，三种水泥胶砂的收缩都是随着龄期的增加而增加，在20天以后收缩增长趋于平缓，在这之前的增长幅度比较大；在3天之前，三种水泥胶砂的干缩率区别不大；7天之后，低热硅酸盐水泥的干缩率渐渐与其他两个型号的水泥区别开来，且在60天的时候其干缩值也比其他两种小，从而我们就可以知道低热硅酸盐水泥与其他两种水泥相比较，可能因为它特有的浆体的孔结构相关，具有比较良好的体积稳定性。

2.抗冲击性能
为了对比不同的水泥对混凝土性能的影响，在检测水泥对路面混凝土抗冲击性能的影响时剔除了粗骨料，直接用砂浆的抗冲击性能
来说明水泥的影响程度。

3 种水泥胶砂 28天、60天和 90天龄期的抗冲击性能检测结果见下图。

从图中可以看出，与通用硅酸盐水泥相比，低热水泥胶砂有着优异的抗冲击性能，无论是 28d 还是在长龄期，从数据上反映它的抗冲击性能要远超出 1 号
和 2号样。

3.耐磨性能
以混凝土为试样，试验结果以耐磨度来表征，耐磨度的含义是：材料磨损至一定深度所能经受的磨损力作用。

耐磨度按下式计算。

上图是耐磨性测试的结果，从图可以看出，当混凝土构件进入28天龄期时，3号样的耐磨度最小，耐磨性能也最差，但是与 2号样的差距并不大。

到了 60d 和 90d，其耐磨度有了大幅增长，超过了 1号和2号样。

因为在进行耐磨性检测的时候，往往是针对混凝土构件的表层，所以混凝土构件表层浆体的致密性与胶凝性在很大程度上对于其耐磨性起着决定性的作用。

这主要是由于3号样低热混凝土构件里面较多的b矿物质，在其余条件都一样的背景之下，到达28天龄期的时候通用硅酸盐水泥的水化程度往往要高于低热硅酸盐水泥的水化程度，所以导致3号低热硅酸盐水泥浆体里面的胶凝性与致密性会低于1号样和2号样。

但是当龄期到达60天与90天的时候，还没有完全水化的b矿物质可以照样进行水化，在此
时低热硅酸盐水泥的整体水化程度已经大大超过另外两个样，而且质量相同的ca2sio4与ca3sio2水化之后会得到更多的c-s-h凝胶，进而将低热硅酸盐水泥浆体的致密性与胶凝性有效地提高了，最终提升了低热硅酸盐水泥构件的耐磨性。

4.热分析
3 种水泥净浆试样的 90d 龄期时的热分析，经测试3 个试样在105.4℃、 106.8℃以及 104.7℃时都有明显的吸热峰，这是水化硅酸钙凝胶和钙矾石的脱水效应，从相对应的 tg 曲线可以计算出 1号、 2号和 3号 3 个样在此温度下的失重分别为
12.25% 13.80%、14.52%；其次，在 450℃附近 3 个 dta 曲线也都有明显的吸热峰，这是 ca(oh)2 的脱水吸热效应，它们的失重比例分别为5.01%、 4.87%、4.27%。

通过 tg曲线的计算可知，90d 龄期时，3号水泥水化产物中生成的凝胶的量最多，而晶体含量最少，因此 3号的晶胶比必然最小，使得其道路混凝土具有较小的脆性，较好的抗冲击性能。

同时，大量凝胶的生成提高了浆体的致密性，阻断了孔与孔之间的连通，减少了连通孔，减小了水分的散失，使得低热水泥胶砂的干缩较小。

因此，在粗骨料相同的情况下，低热水泥道路混凝土具有更好的干缩性能和体积稳定性。

三、结论
1.低热水泥胶砂具有较小的干缩率，在相同粗骨料的影响因素下，其道路混凝土的也应具有较小的干缩率，更好的体积稳定性。

2.与通用硅酸盐水泥相比，低热水泥水化产物具有较小的晶胶
比，水泥胶砂的脆性小，抗冲击性能也好；因此在粗骨料相同的情况下其混凝土也有较小的脆性及较好的抗冲击性能。

3.通过低热水泥胶砂的性能可以看出，低热水泥后期持续的水化能力有利于提高其道路混凝土的耐久性，提高路面的使用寿命，将其应用于道路混凝土具有实际工程意义和广泛的应用前景。

4.通过低热水泥胶砂的性能可以看出, 低热水泥后期持续的水化能力有利于提高其道路混凝土的耐久性, 提高路面的使用寿命, 将其应用于道路混凝土具有实际工程意义和广泛的应用前景。

参考文献：
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[2]冯乃谦.实用混凝土大全[m].北京:科学出版社，2001.
[3]杨南如,岳文海.无机非金属材料图谱手册[m]. 武汉:武汉理工大学出版社,2000.
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