河砂和骨料对UHPC性能的影响研究

STUDY ON THE EFFECT OF ORDINARY RIVER SAND AND COARSE AGGREGATE ON THE BASIC PROPERTIES OF ULTRA-HIGH PERFORMANCE CONCRETE

文中通过采用普通河砂替代石英砂及掺入粗骨料,研究其对超高性能混凝土(UHPC)基本性能的影响,制备出性能良好、成本较低的UHPC,以推动UHPC在土木工程中更广泛的应用。试验结果表明,随着河砂掺量的增加,UHPC的工作性能逐步提高,UHPC的力学性能先升高后降低,河砂掺入30%时抗压强度、抗折强度达到最大值,UHPC的抗拉强度不断降低,UHPC的耐久性能因抗氯离子渗透性能的提高而更加优异;河砂掺量50%、粗骨料体积掺量15%的UHPC的工作性能、抗折强度、抗拉强度及耐久性能有所降低,但其抗压强度提高明显,具有一定实用性。

The UHPC with good performance and low cost was produced and promoted the wider application in civil engineering. The effects of ordinary river sand and coarse aggregate on the basic properties of UHPC were studied in this paper. The results showed that the performance of UHPC improved and the tensile strength decreased continuously with the increase of river sand content. The mechanical properties of UHPC showed a trend of first rising and then falling with the increase of river sand content,and the compressive strength and flexural strength reached the maximum when the river sand mixed with 30%. The durability of UHPC was enhanced by the improvement of anti-chloride-permeability performances with the increase of river sand content. When the river sand content was 50% and the coarse aggregate volume content was 15%, the working performance, flexural strength, tensile strength, and durability of UHPC were reduced,indicating the compressive strength of UHPC was improved obviously.