BACKGROUND One ideal property of a root-end filling material is its apical sealing ability. The aim of this in vitro study was to assess bacterial and dye microleakage of white and gray mineral trioxide aggregate (WMTA and GMTA), Portland cement and calcium-enriched mixture (CEM) cement used as root-end filling material, and to assess the agreement between these two test methods. MATERIALS AN...

As the one of environmental-conscious concrete, equivalent for type A portland blast-furnace slag cement is due to concomitant use ordinary and B cement. In this research, considered about concrete which made accumulation weighing used these cements. results, performances were equally with Portland Moreover, influence be assumed error properties such as compressive strength development carbonat...

In the cellulose industry the Kraft process is widely used to produce cellulose. This process generates huge volumes of inorganic solid wastes, including the grits waste. In Brazil, the final disposal of this solid waste is of high economical and environmental interest. The present work assesses the influence of the addition of grits waste on the densification behavior of soil-cement bricks. Th...

Stephen S. Szoke, P.E., LEED/AP, FACI Director, Codes and Standards Portland Cement Association 5420 Old Orchard Road, Skokie, IL 60077 +1-847-972-9078 [email protected] Stephen V. Skalko, P.E. Manager, Regional Code Services Portland Cement Association 128 Summerfield Drive, Macon, GA 31210 +1-478-477-5028 [email protected] A paper presented at the April 23-25, 2012 The Infrastructure Security...

This article describes an improvement on a previous model proposed by Ba~ant and Najjar, in which moisture diffusivity and moisture capacity are treated as separate parameters. These parameters are evaluated from independent test results, and are shown to depend on the water:cement ratio, curing time, temperature, and cement type. The moisture capacity is obtained as the slope of the adsorption...

Estimation of water soluble hexavalent chromium and total chromium has been devised. For the complete extraction of water soluble hexavalent chromium, leaching period of five days is done. It was ascertained that complete extraction was achieved in five days; the total chromium determination in these samples was done by fusing sample with sodium carbonate up to 1050 C in muffle furnace. Chromiu...

MODELING OF HYDRATION KINETICS AND SHRINKAGE OF PORTLAND CEMENT PASTE

OBJECTIVE This study compared the chemical constitution, radiopacity, and biocompatibility of Portland cement containing bismuth oxide (experimental cement) with those of Portland cement and mineral trioxide aggregate (MTA). STUDY DESIGN The chemical constitution of materials was determined by scanning electron microscopy and energy-dispersive X-ray analysis. The radiopacity of the materials ...

Cement manufacture has undergone extensive change in its attempts to rise to the successive challenges posed by society. The hydration of Portland cement is a complex phenomenon that depends on both reagent characteristics and reaction conditions. It is a well-known fact that the curing temperature plays an important role on the hydration kinetics. The present study is the first to be undertake...