mso-hansi-font-family:"Times New Roman"">一、产品概述:
mso-hansi-font-family:"Times New Roman"">混凝土抗冲刷试验机是利用高速离心力旋转叶轮转动水流冲击混凝土内环表面磨损的试验,以测定各类混凝土表面抗水流冲击磨损的能力。
mso-hansi-font-family:"Times New Roman"">二、依据标准:
mso-hansi-font-family:"Times New Roman"">根据《水工混凝土试验规程DL/T5150-2001 "Times New Roman"">》规定的技术要求设计生产
mso-hansi-font-family:"Times New Roman"">三、仪器设备:
1、钢球冲磨仪主要部件包括:
(1)驱动装置,能夹固搅拌桨并使其以1200r mso-hansi-font-family:"Times New Roman"">/min "Times New Roman"">速度旋转的电机装置:
(2)钢筒:内径为305mm mso-hansi-font-family:"Times New Roman"">±6mm "Times New Roman"">,高450mm "Times New Roman"">±25mm,下边四周有螺孔。
(3)钢底座:
(4)搅拌桨;
(5)研磨料:70 mso-hansi-font-family:"Times New Roman"">个按下表规定的研磨钢球。
mso-hansi-font-family:"Times New Roman"">直径mm25.4 "Times New Roman"">±0.1*10 "Times New Roman"">个;19.1±0.1*35 mso-hansi-font-family:"Times New Roman"">个;12.7 "Times New Roman"">±0.1*25 "Times New Roman"">个
2、试模:金属圆模,内径300mm mso-hansi-font-family:"Times New Roman"">±2mm "Times New Roman"">,高100mm "Times New Roman"">±lmm。
3、天平:称量20Kg mso-hansi-font-family:"Times New Roman"">,感量1g "Times New Roman"">。
mso-hansi-font-family:"Times New Roman"">四、试验步骤:
1、按“混凝土试件的成型与养护方法”制备试件:允许骨料**粒径为40mm mso-hansi-font-family:"Times New Roman"">,试验以三个试件为—组。
2、试验前,试件需在水中至少浸泡48h mso-hansi-font-family:"Times New Roman"">。
3、试验时,取出试件,擦去表面水份,称量。
4、钢筒与底座间放上橡皮垫圈,在底板上垫上两根Φ6mm mso-hansi-font-family:"Times New Roman"">的钢筋,把已称量过的混凝土试件放在钢筋上并对中,且使混凝土表面垂直于转轴,套上钢筒,旋紧固定钢筒与底座的螺栓,使其密封。
5、将搅拌桨安装在转轴上,搅拌桨底部距试件表面约38mm mso-hansi-font-family:"Times New Roman"">,调整钢筒和底座的位置使转轴对中。
6、在钢筒内放入研磨钢球于试件表面,并加水至水面高出试件165mm mso-hansi-font-family:"Times New Roman"">。
7、确认转轴转速在:1200r mso-hansi-font-family:"Times New Roman"">/min "Times New Roman"">后,开机。
8、每隔24h mso-hansi-font-family:"Times New Roman"">,在钢筒内加1 "Times New Roman"">—2次水至原水位高度。
9、累计冲磨72h mso-hansi-font-family:"Times New Roman"">,取出试样,清洗干净,擦去表面水份称量。
mso-hansi-font-family:"Times New Roman"">五、试验结果处理:
1、混凝土抗冲磨指标以抗冲磨强度或磨损率表示。
1)抗冲磨强度按式计算:
mso-hansi-font-family:"Times New Roman"">式中:
mso-hansi-font-family:"Times New Roman"">∫a=
mso-hansi-font-family:"Times New Roman"">式中:∫a "Times New Roman"">——抗冲磨强度,即单位面积上被磨损单位质量所需的时间,h/(kg "Times New Roman"">/m2)
T——试验累计时间:h mso-hansi-font-family:"Times New Roman"">:
A——试件受冲磨面积m2
mso-hansi-font-family:"Times New Roman"">△M "Times New Roman"">——经T时段冲磨后,试件损失的累计质量Kg mso-hansi-font-family:"Times New Roman"">。
2)磨损率按式计算:
mso-hansi-font-family:"Times New Roman"">式中: L——磨损率,%;
Mo——试验前试件质量,Kg mso-hansi-font-family:"Times New Roman"">;
MT——试验后试件质量,Kg mso-hansi-font-family:"Times New Roman"">。
mso-ansi-language:EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">2 "Times New Roman";mso-font-kerning:1.0pt;mso-ansi-language:EN-US;mso-fareast-language: ZH-CN;mso-bidi-language:AR-SA">、以一组三个试件测值的平均值作为试验结果,如单个测值与平均值的差值超过 mso-fareast-font-family:宋体;mso-font-kerning:1.0pt;mso-ansi-language:EN-US; mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">15 "Times New Roman";mso-font-kerning:1.0pt;mso-ansi-language:EN-US;mso-fareast-language: ZH-CN;mso-bidi-language:AR-SA">%时,则此值应剔除,以余下两个测值的平均值作为试验结果,若一组中可用的测值少于两个,则该组试验应重做。