§4.7Advanced Concrete

4.7.1 The Sixth Composite of Concrete

4.7.2 High-strength Concrete (HSC)

4.7.3 High Performance Concrete (HPC)

4.7.4 Pumped Concrete

4.7.5 Non-dispersion Concrete in Water (NDC)

4.7.6 Seawater-resistant concrete

4.7.7 Green Concrete

4.7.1 The Sixth Composite of Concrete

• Introduction

• Reformed Type

• Functional Type

• Intelligent Type

• The sixth composite of concrete refers to the composite used to improve concrete performance, provide with more functions or make the concrete intelligent, besides cement, water, sand and chemical admixture.

• By feature it can be classified into– reformed type– functional type – intelligent type

Introduction

Reformed Type

• The reformed type is designed to improve concrete physical property

• It contains – mineral admixture– polymer – fibre

Mineral Admixture • Mineral admixture refers to some fine a

nd active mineral material added in bleeding to improve concrete mixture and hardening concrete (esp. durability ).

• It has the following kinds silica fume, grinding fly ash, slag micronization, zeolite powder, kaolin and its complex.

Reformed Type

Polymer

• Polymer concrete and mortar are mainly influenced by polymer type and its quantity.

Reformed Type

Fibre • If added with fibre, such as carbon fibre, st

eel fibre, organic fibre, the traditional concrete will have great improvement in tensile, toughness, crack resistance, fatigue resistance.

Fig.4.7.1Load-deflection Curve of Composite Materials in Fibre Reinforcement Cement

Conductive Concrete • There is a critical point in conductive

composite.• When its quantity exceeds the critical point,

conductivity of the composite materials will increase dramatically.

Reformed Type

Fig. 4.7.2 Relation between Conductivity of the Composite Materials and Quantity of Carbon Fibre

Functional Type • The functional type of composite can provi

de special functions– for example

• radiation protection• static protection• shrinkage water• anti-abrasion• heat reservation• heat insulation

• It is mainly applied in making functional concrete, such as– conductive concrete– shielded electromagnetism radiation concrete– shielded magnetic concrete

Intelligent Type

• Temperature Temperature sself-monitoring elf-monitoring cconcreteoncrete• Animated self-healing concreteAnimated self-healing concrete• Traffic navigation concreteTraffic navigation concrete• Self-diagnoses concreteSelf-diagnoses concrete• Moisture-adjustable concreteMoisture-adjustable concrete

• Within the maximum difference of temperature of l5℃and the highest of 70℃ , electromotive force E and maintain a steady linearity relation Fig4.7.3.

• As the curing age prolongs the electromotive force ratio takes on a stable tendency (Fig.4.7.4).

Temperature self-monitoring concrete

Fig.4.7.3 Relation between Electromotive Force and Difference of Temperature

Fig. 4.7.4 Influence of the Electromotive Force Ratio by Curing Age

Animated self-healing concrete

Fig. 4.7.5 Illustration of Animated Self-healing Concrete Mechanism