\r細集料棱角性測定儀<\/span> <\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r適用范圍<\/span> <\/span>\r<\/p>\r\r WX-2000<\/span>細集料棱角性測定儀用于測定一定體積的細集料（機制砂、石屑、天然砂）全部通過標準漏斗所需要的流動時間，稱為細集料的棱角性，以<\/span>s<\/span>表示。<\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r主要結(jié)構(gòu)：<\/span>\r<\/p>\r\r 細集料流動時間測定儀，如圖所示，上部為直徑<\/span>90mm<\/span>，高<\/span>125mm<\/span>的金屬圓桶，下部為更換的開口<\/span>60<\/span>°的金屬或硬質(zhì)塑料漏斗，漏斗內(nèi)部應(yīng)光滑，其流出孔直徑有兩種可更換的規(guī)格<\/span>12mm<\/span>或<\/span>16mm<\/span>，上部有螺紋與圓筒連成一整體。漏斗下方有一個可以左右轉(zhuǎn)動的開啟擋板，測定儀下方放置一個足以存下<\/span>3kg<\/span>細集料的容器。<\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r主要技術(shù)參數(shù)：<\/span> <\/span>\r<\/p>\r\r 1<\/span>、圓錐筒漏斗：角度<\/span>60<\/span>°±<\/span>2<\/span>°<\/span>\r<\/p>\r\r 2<\/span>、漏斗口直徑：<\/span>12.7mm<\/span>±<\/span>0.3mm<\/span>；<\/span>100ml <\/span>\r<\/p>\r\r 3<\/span>、容器：<\/span>100ml<\/span>±<\/span>5ml <\/span>\r<\/p>\r\r 4<\/span>、斗容間距：<\/span>115mm<\/span>±<\/span>1mm <\/span>\r<\/p>\r\r 5<\/span>、搗棒直徑：<\/span>25mm<\/span>±<\/span>0.5mm <\/span>\r<\/p>\r\r 6<\/span>、搗棒質(zhì)量：<\/span>340g<\/span>±<\/span>5g <\/span>\r<\/p>\r\r 7<\/span>、凈重：<\/span>9kg<\/span>；<\/span> <\/span>\r<\/p>\r\r 8<\/span>、外形尺寸：<\/span>310<\/span>×<\/span>310<\/span>×<\/span>500<\/span>（<\/span>mm<\/span>）<\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r執(zhí)行標準<\/span> <\/span>\r<\/p>\r\r <\/span>嚴格按照<\/span>JTJ058<\/span>—<\/span>2000<\/span>公路規(guī)程設(shè)計的產(chǎn)品<\/span>,<\/span>可完成<\/span>T0344,\rT0330<\/span>試驗。<\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r實驗儀器與材料<\/span> <\/span>\r<\/p>\r\r 1.<\/span>標準篩：孔徑為<\/span>4.75mm<\/span>、<\/span>2.5mm<\/span>、<\/span>0.075mm<\/span>的方孔篩。<\/span> <\/span>\r<\/p>\r\r 2.<\/span>天平：感量不大于<\/span>0.1g<\/span>。<\/span> <\/span>\r<\/p>\r\r 3.<\/span>烘箱：能控溫在<\/span>105<\/span>℃±<\/span>5<\/span>℃。<\/span> <\/span>\r<\/p>\r\r 4.<\/span>秒表：準確至<\/span>0.1s<\/span>。<\/span> <\/span>\r<\/p>\r\r 5<\/span>、玻璃板：<\/span>60mmX60mm<\/span>，厚度<\/span>4mm <\/span>\r<\/p>\r\r 6<\/span>、刮尺：帶刃直尺，長<\/span>100mm<\/span>寬<\/span>20mm <\/span>\r<\/p>\r\r 7<\/span>、其他：搪瓷盤，毛刷<\/span> <\/span>\r<\/p>\r\r <\/span>\r<\/p>\r\r試驗步驟：<\/span>\r<\/p>\r\r <\/span> 1.<\/span>將從現(xiàn)場取來的細集料試樣，按照最大粒徑的不同選擇<\/span>2.36mm<\/span>或<\/span>4.75mm<\/span>的標準篩過篩，<\/span>\r<\/p>\r\r 2<\/span>除去大于最大粒徑的部分。<\/span> <\/span>\r<\/p>\r\r但當(dāng)工程上同時使用不同品種細集料，如將天然砂和機制砂、石屑混用時，應(yīng)分別進行單一細集料品種的棱角性質(zhì)量評定，同時以實際配合比例組成的細集料混合料進行試驗，以評定其使用性能。<\/span> <\/span>\r<\/p>\r\r 3.<\/span>按<\/span>T0327<\/span>方法以水洗法除去小于<\/span>0.075mm<\/span>的粉塵部分，取<\/span>0.075mm~2.36mm<\/span>或<\/span>0.075mm~4.75mm<\/span>的試樣約<\/span>6kg<\/span>放入<\/span>105<\/span>℃±<\/span>5<\/span>℃烘箱中烘干至恒干至恒重，<\/span>2<\/span>在室溫下冷卻。<\/span> <\/span>\r<\/p>\r\r 4.<\/span>按本規(guī)程<\/span>T0328<\/span>的方法測定試樣的表觀相對密度У<\/span>a<\/span>，用分料器法或四分法將試樣分成不少于<\/span>5<\/span>份，按下式計算每份試樣所需的質(zhì)量，稱量準確至<\/span>0.1g<\/span>。<\/span> <\/span>\r<\/p>\r\r m=1.0<\/span>×У<\/span>a/2.70 <\/span>\r<\/p>\r\r 式中：<\/span>m<\/span>—每份試樣的質(zhì)量（<\/span>kg<\/span>）；<\/span>\r<\/p>\r\r У<\/span>a<\/span>—該試樣的表觀相對密度，無量綱。<\/span>\r<\/p>\r\r 5.<\/span>根據(jù)試驗的細集料規(guī)格選擇漏斗，對規(guī)格<\/span>0.075mm~2.36mm<\/span>的細集料選用漏出孔徑為<\/span>12mm<\/span>的漏斗，對規(guī)格<\/span>0.075mm~4.75mm<\/span>的細集料選用孔徑為<\/span>16mm<\/span>的漏斗，將漏斗與圓筒連接安裝成一整體。關(guān)閉漏斗下方的開啟門，在漏斗下方置接受容器。<\/span>\r<\/p>\r\r 6.<\/span>將試樣從圓筒中央開口處（高度與筒頂齊平）徐徐倒入漏斗，表面盡量倒平，但倒完后不得以任何工具擾動或刮平試樣。<\/span>\r<\/p>\r\r 7.<\/span>在打開漏斗開啟門的同時開動秒表，漏斗中細集料隨時即從漏斗開口處流出，<\/span>2<\/span>進入接受容器中。在細集料全部流完的同時停止秒表，讀出細集料流出的時間，準確至<\/span>0.1s<\/span>，即為該細集料試樣的流動時間。<\/span>\r<\/p>\r\r 8.<\/span>一次試驗需平行試驗<\/span>5<\/span>次，以流動時間的平均值作為細集料棱角性的試驗結(jié)果。<\/span>\r<\/p>
