This paper deals with the issues of air entraining and water/cement ratio in Portland Cement Concrete as related to its freeze thaw durability. Practices have been in place for nearly thirty years which demanded high early strengths in Portland Cement Concrete pavements. This paper looks at those practices, investigates the correlation between water/cement ratio and air entraining, and presents...

Infections in orthopaedic surgery are a serious issue. Antibiotic-loaded bone cement was developed for the treatment of infected joint arthroplasties and for prophylaxes in total joint replacement in selected cases. Despite the widespread use of the antibiotic-loaded bone cement in orthopedics, many issues are still unclear or controversial: bacterial adhesion and antibiotic resistance, modific...

The production of cement results in emission of many green house gases in atmosphere, which are responsible for global warming. Hence, the researchers are currently focused on use of waste material having cementing properties, which can be added in concrete as partial replacement of cement, without compromising on its strength and durability, which will result in decrease of cement production t...

The rheological properties of blended cement-based materials depend strongly on mixture proportions and the characteristics of the components. In this study, design of experiments is used to investigate the influence of three variables (cement particle size distribution (PSD), fly ash PSD, and ratio of fly ash to cement) at each of four levels on the yield stress and viscosity of blended pastes...

New polymeric calcium phosphate cement composites (CPCs) were developed. Cement powder consisting of 60 wt% tetracalcium phosphate, 30 wt% dicalcium phosphate dihydrate, and 10 wt% tricalcium phosphate was combined with either 35% w/w poly methyl vinyl ether maleic acid or polyacrylic acid to obtain CPC-1 and CPC-2. The setting time and compressive and diametral tensile strength of the CPCs wer...

Use of antibiotic-loaded bone cement for prophylaxis against infection is not indicated for patients not at high risk for infection who are undergoing routine primary or revision joint replacement with cement. The mechanical and elution properties of commercially available premixed antibiotic-loaded bone-cement products are superior to those of hand-mixed preparations. Use of commercially avail...

Properties of cement pastes with fine-ground ceramics used as an alternative binder replacing Portland cement up to 20% of its mass are investigated. At first, the particle size distribution of cement and fine-ground ceramics is measured using laser analyser. Then, the material properties are studied in the early hardening period up to 28 days. The hydration process of studied materials is moni...

In this paper we develop a Model Predictive Controller (MPC) for regulation of a cement mill circuit. The MPC uses soft constraints (soft MPC) to robustly address the large uncertainties present in models that can be identified for cement mill circuits. The uncertainties in the linear predictive model of the cement mill circuit stems from large variations and heterogeneities in the feed materia...

The paper compared the effect of additives such as FeSO4.7H2O and SnCl2.2H2O on reduction of water soluble Cr(VI), in ordinary Portland cement (43 grades). The determination of water soluble Cr(VI) from cement samples was precisely conducted by DPC-Spectrophotometer technique. The compressive strength testing of the cement mortar samples was carried out. In addition, hydration properties of cem...

The objective of this study was to evaluate the sealing ability and antibacterial activity of Ca3SiO5/CaCl2 composite cement. Fifty maxillary anterior teeth were instrumented according to step-back technique and filled with experimental and control materials. To evaluate the sealing ability, a fluid transport model using glucose was employed for quantitative analysis of endodontic microleakage....