﻿ 建立再碱化技术修复火害后钢筋混凝土之pH值控制模式 Modelling of pH Value for Electrochemical Realkalisation to Repair of Fired-Damaged Reinforced Concrete

Hans Journal of Civil Engineering
Vol.04 No.02(2015), Article ID:15025,7 pages
10.12677/HJCE.2015.42012

Modelling of pH Value for Electrochemical Realkalisation to Repair of Fired-Damaged Reinforced Concrete

Chih-Ming Lin

Department of Architecture, National Taitung Junior College, Taitung City

Email: lin56@ntc.edu.tw

Received: Mar. 12th, 2015; accepted: Mar. 25th, 2015; published: Mar. 31st, 2015

ABSTRACT

The passive film in internal reinforcement corrosion was destroyed by the fire-damaged of reinforced concrete. However, the destruction of the passive film is caused by the disappearance of the alkaline environment around reinforced corrosion. This study was to establish the modeling pH value for electrochemical realkalisation to repair of fired-damaged reinforced concrete. The pH value of fire-damaged reinforced concrete is determined by the equation , in which is the circuit current density (A/ m2), is power-on time (s), is neutral depth (mm), is actual strength of concrete after fire-damaged (MPa), is the parameter of porosity. The parameter of of porosity for the ordinary strength fire-damaged is 6.3 × 10−4, while the high-intensity fire-damaged is 2.5 × 10−5. This equation can be used to estimate the pH value for fire-damaged reinforced concrete to repair by electrochemical realkalisation.

Keywords:Electrochemical Realkalisation, Fire-Damaged Reinforced Concrete, pH Value, Modelling

Email: lin56@ntc.edu.tw

1. 引言

1) 电解

2. 研究方法

1) 碱化过程中电流在与电解质接触的混凝土表面上均匀分布；

2) 钢筋混凝土构筑物火灾前的碳化和火灾造成的碳化相比可以忽略；

3) 电解液中仅考虑人为加入的电解质离子，忽略其他离子的导电性能；

4) 电解后停留在钢筋周围的OH均匀分布在火灾后中性化的混凝土保护层内。

2.1. 一般钢筋混凝土再碱化技术OH浓度控制模式

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

2.2. 火害后钢筋混凝土再碱化技术浓度控制模式

(9)

(10)

(11)

(12)

2.3. 火害后钢筋混凝土再碱化技术pH值控制模式

(13)

(14)

(15)

(16)

(17)

(18)

2.4. 钢筋混凝土pH 值控制模式的确认

Table 1. Flow chart to illustrate the pH value model of fire-damaged reinforced concrete to repair by electrochemical realkalization

3. 利用pH值控制模式的应用

3.1. 损伤深度检测

3.2. 实施电化学再碱化修复

3.3. pH值控制模式的应用

4. 结论

Table 2. Predictive k value of porosity was estimated by modelling of pH value in fire-damaged reinforced concrete to repair by electrochemical realkalisation

Table 3. Predicted pH value and actual pH value of fire-damaged reinforced concrete

Modelling of pH Value for Electrochemical Realkalisation to Repair of Fired-Damaged Reinforced Concrete. 土木工程,02,94-101. doi: 10.12677/HJCE.2015.42012

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