輕質骨材混凝土泵送性質之研究

A Study of Pumping of Lightweight Aggregate Concrete

梁志豪(Chih-Hao Liang)

指導教授 ： 干裕成

朝陽科技大學/理工學院/營建工程系/碩士(2012年)

摘要

本研究主要探討在泵送壓力作用下，輕質骨材混凝土骨材之吸水行為及對輕質混凝土強度發展的影響。研究試驗規畫內容，係以等值長度120 m之水平泵送(相當於垂直泵送15 m)為主；試驗管線中並在三個不同位置，設置壓力觀測點，監測管壓之變化。研究試驗結果發現，輕質骨材混凝土在水平泵送過程中，泵送距離愈長，泵送輸出壓力越大；但在水平泵送過程中，各監測點混凝土所受之壓力變化不大。但隨著泵送輸出壓力與泵送距離的增加，將造成坍度與坍流度等工作度之損失，且水灰比會因此減小，導致混凝土強度隨泵送吸水率增加而增加。另外，因水平泵送壓力造成吸水率的減少，及其對於後續強度發展的影響，在本文中也做進一步探討。

關鍵字

輕質混凝土 ； 泵送

並列摘要

This study investigated the influence of pumping pressure on water absorption of lightweight aggregate and strength of concrete. A horizontal pipeline including a 96 m long with two 90˚ angles pipes in the pipeline - equivalent to a 120 m pumping length, were designated in this study. The pressures of pumping concrete against the pipe wall were monitored in three locations - 45 m, 51 m and 72 m from the pumping cart. The test results showed that a longer horizontal pumping distance needs a greater driving pressure for pumping concrete. The pressures being observed during pumping process in three different locations appear little variance once workability is assured. The losses of both slump and fluid slump increase with the driving pressure as well as pumping length. In addition, the increase of pumping absorption of lightweight aggregates due to driving pressure results in a reduction of water-to-cement ratio and a higher gain of strength.

並列關鍵字

lightweight concrete ； pumping

參考文獻

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16.Denis Kaplan, Francois de Larrard, and Thierry Sedran,「Avoidance of Blockages in Concrete Pumping Process」, ACI Materials Journal, Vol. 102(Iss3), 2005 , pp.183-191.

19.Browne, R.D., Bamforthe, P.B. 「Tests to Establish Concrete Pumpability」, ACI Journal, Vol. 74, No. 5, 1977 , pp. 193-207.

1.How-Ji Chen, Shuen-Yuan Wang, Hui-Wen Liao, and Kuo-Chang Jane, 「Thermal Behavior and Expansion Mechanism of the Reservoir Sediments Lightweight Aggregate」, International Conference on Concrete and Reinforced Concrete - Development Trends, Vol.4, pp. 169-175, 5-9 September 2005, Moscow, Russia.