A Comparative Study on the Degradation of Alkali-Activated Slag/Fly Ash and Cement-Based Mortars in Phosphoric Acid

This study compares the degradation behavior of the alkali-activated slag/fly ash (AASF) and ordinary Portland cement (OPC) mortars exposed to phosphoric acid with different pH values. The experimental results show that AASF mortars exhibit better resistance than OPC mortars against surface damage, although both systems get white deposits on the...

Compressive strength and pore structure studies of clamp-fired waste powdered clay brick as a supplementary cementitious material

Clamp-firing system is a cost-effective technology used to produce burnt clay bricks in many West African countries including Ghana. However, this firing system generates between 7%- 15% of waste in a form of burnt broken bricks and with time creates disposal problems. In this work, burnt clay broken bricks were sampled and pulverised to 75...

Prediction of the chemical shrinkage of Portland cement

Chemical shrinkage is one of the main reasons leading to the early age deformation of concrete. Hence, the prediction of chemical shrinkage is an important issue for evaluating the deformation of concrete and its influence on the durability of concrete structures. There is still room to improve the accuracy for predicting the chemical shrinkage...

Prediction of the chemical shrinkage of Portland cement

Chemical shrinkage is one of the main reasons leading to the early age deformation of concrete. Hence, the prediction of chemical shrinkage is an important issue for evaluating the deformation of concrete and its influence on the durability of concrete structures. There is still room to improve the accuracy for predicting the chemical shrinkage...

Evaluation of RRSB distribution and lognormal distribution for describing the particle size distribution of graded cementitious materials

Graded blended cement made of graded Portland cement (PC), blast furnace slag (BFS) and fly ash (FA) is attractive for cement production. For manufacturing graded blended cement, a suitable mathematical expression should be introduced to describe the particle size distribution (PSD) of its components and control the quality of graded blended...

A coupled transport-reaction model for simulating autogenous self-healing in cementitious materials. Part II: Validation through comparison with experiments

In this paper, the proposed coupled transport-reaction model adapted to simulate autogenous self-healing in Portland cement paste is validated with the experimental results. The parameters are studied for modelling the dissolution of cement, the diffusion of ions between the solution in the crack and in the bulk paste and the precipitation of...

Ageing of portland cement concrete cured under moist conditions

Deterioration of microstructure in cement concrete will cause changes in the transport properties of the concrete. Transport properties at different ages of the concrete provide information about the microstructural changes of the material. A way to measure the transport properties, i.e. the chloride diffusion coefficient, in the laboratory is...

Microstructure and deterioration mechanisms of Portland cement paste at elevated temperature

Study of ‘real’ shrinkage by ESEM observations and digital image analysis

Defining the 'real' shrinkage values of concrete is still a subject of much debate. In shrinkage experiments size effects are inherently present. Through an attempt to determine the real shrinkage of cement-based materials, these size effects have to be eliminated or at least reduced as much a possible. In this contribution drying shrinkage...

Durability of Marine Concrete under Thermal Cycling Loads

Data on chloride penetration into concrete exposed to a simulated aggressive marine environment are presented. Concrete specimens, large beams and small cubes, are subjected to 90 complete exposure cycles of wetting and drying plus heating and cooling. The applied exposure condition consists of a drying period of 42 hrs followed by a wetting...