自充填混凝土火害後強度之基因演算模式分析

Residual strength of Self-Compacting Concrete after Fire Exposure-Analysis using Genetic Algorithm

廖育陞(Yu-sheng Liao)

指導教授 ： 江支弘

朝陽科技大學/理工學院/營建工程系/碩士(2009年)

摘要

混凝土為現代結構物不可或缺的一項材料，並且被視為是能夠有效抵抗高溫破壞，可是在火害溫度及延燒時間增加的情況下，仍會造成混凝土性質的改變，其中強度折減為其中最重要的一項改變，故本研究將火害相關的參數如溫度、延燒時間以及波速導入基因演算法中，針對火害後自充填混凝土強度建立基因演算法模型，期望能有效的預測火害後混凝土強度與其價值。
程式模型計算結果發現，殘餘強度預測差異大致上在1%~5%之間，其中240℃的程式結果差異相較於其它溫度都還要來的大，故可在研究中於適度函數資料數量應當增加，用以縮短網格間的間距，以獲得較準確的搜尋結果。

關鍵字

適度函數 ； 自充填混凝土

並列摘要

Concrete is considered to be fire-endurable among construction materials. However, the strength of concrete will deteriorate subject to fire exposure as exposure time and temperature are increased. Experimental work was conducted for analyzing the residual strength of self-compacting concrete. Measurements of ultrasonic pulse velocity were taken before and after the specimens were treated in an electrical oven. A computer model was constructed based on the genetic algorithm. Prediction of residual strength can be made using input parameters including exposure time, exposure temperature, and pulse velocity. The difference between predictions and measurements is within 5%. A smaller grid size in the fitness function may be achieved should more experimental data be available. This could be helpful to improve the accuracy of the predictions of residual strength.

並列關鍵字

SCC ； Fitness Function

參考文獻

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