HRB500级钢筋活性粉末混凝土梁受弯性能试验研究

Experimental study on flexural property of reactive powder concrete beams with HRB500 steel

通过5根配置HRB500级或HRB400级钢筋活性粉末混凝土简支梁的受弯性能试验,分析试验梁在各级荷载作用下的裂缝分布与开展情况。根据实测数据,验证现行混凝土规范有关受拉区裂缝间距和最大裂缝宽度等计算公式对于试验梁的适用性,并提出了极限弯矩的计算方法。研究表明:试验梁的裂缝分布及宽度与配筋率、钢筋直径和钢筋等级等参数相关;计算高强钢筋活性粉末混凝土梁的正截面承载力时,应考虑活性粉末混凝土的抗拉强度和钢纤维的拉结作用,受拉区等效塑性系数k可取0.3。

An experimental study was conducted to investigate the flexural property of 5 reactive power concrete beams with HRB400 or HRBS00 steel. The crack distribution and development in test beams were analyzed under various stepwise loadings. According to the measured datum, the applicability of tensile area crack spacing and maximum crack width calculation formulas in current concrete code for test beams were verified, and the computing method of the ultimate bending moment was suggested. The research shows that the crack distribution and width of test beams relate to parameters like reinforcement ratio, steel diameter, steel grade and so on. To calculate the normal section bearing capacity of high strength reinforced reactive powder concrete beams, the tensile strength of reactive powder concrete and the tying effect of steel fiber should be considered, and the equivalent plastic coefficient k within tensile region is set to 0. 3.