For rehabilitation of damaged concrete structures, the durability of repair overlay is a very important issue. Self-compacting concretes (SCC) are known as a suitable repair overlay materials. In this study, the durability of different self-compacting lightweight aggregate concretes (LWSCC) and effect of lightweight aggregate type on them is investigated. 3 mix designs of LWSCC containing three...

Activation of class F fly ash with the 10 M sodium hydroxide and sodium silicate and its geopolymeric products were analysed under quasi-isothermal mode of DSC, FTIR and TG/DTA techniques. Before adding in concrete, expanded polystyrene beads were prewetted with the styrenebutadienestyrene latex aimed at to improve their bonding with geopolymer. Lightweight mortars/concretes were made from geop...

A new patented lightweight aggregates is tested. This type is given the name Flashag. The only solid raw material used to manufacture these aggregates is fly ash. The aggregates are sintered but not pelletized and the process is easy and inexpensive. This paper describes these patented aggregates and compares them with other lightweight and normal-weight aggregates that are used for concrete. T...

This paper presents an analytical method for the calculation of the neutron ambient dose equivalent H* (10) regarding patients, whereby the different concrete types that are used in the surrounding walls of the treatment room are considered. This work has been performed according to a detailed simulation of the Varian 2300C/D linear accelerator head that is operated at 18MV, and silver activati...

Research has focused on increasing the treatment integrity of school-based interventions by utilizing performance feedback. The purpose of this study was to extend this literature by increasing special education teachers' treatment integrity for implementing antecedent and consequence procedures in an ongoing behavior support plan. A multiple baseline across teacher-student dyads (for two class...

In the field of sustainable construction materials, production eco-friendly concretes, obtained by addition waste products such as biochar and recycled polymer particles, offers interesting alternatives to traditional materials. Biochar is a carbonaceous solid by-product from thermo-chemical conversion biomass its into concrete admixtures can offer an carbon sequestration solution, capable slig...

This paper present the results of mechanical properties hybrid reinforced concrete made by adding polypropylene and steel fibers into mixture. For testing purposes were used with hooked ends monofilament fibers. The total 5 batches made: addition fibers, their combination in amount 0,5 % volume. test show that concretes 0.4% 0.1% have better performance compared to other concretes.

The main issue in working with fresh concrete is the workability during filling of formwork. One of the problems found in workability is occurence of segregation depending on w/c ratio. Segregation is strongly related to w/c ratio. The fresh concrete is usually considered as a non-Newtonian fluid since it is a mixture of aggregate, cement and water. The flow behaviour of the fresh concrete, a c...

While high volume fly ash (HVFA) concretes can be designed and produced to meet 28-d strength requirements and often even exceed the durability performance of conventional concretes, a persistent problem is the potentially long delay in setting time that produces concurrently long delays in finishing the concrete in the field. Previous isothermal calorimetry studies on two different powder addi...