Evaluating the cutting rate (CR) of stones is important in the cost estimation and the planning of the stone processing plants. This research used regression models to estimate the stones’ CR based on their physico-mechanical characteristics. Stone processing factories in Mahallat City (Markazi province, Iran) were visited, and the CR of diamond circular saws was recorded on six different travertine stones. Next, the stone block samples were collected from the quarries for laboratory tests. Stones’ porosity (n), uniaxial compressive strength (UCS), and Schmidt hammer hardness (SH) were determined in the laboratory as their physico-mechanical characteristics. Correlation relationships of CR with physico-mechanical characteristics were evaluated using simple and multiple regression analyses, and estimator models were developed. Results showed that multiple regression models are more reliable than simple regression for estimating the stones’ CR. The validity of the developed multiple regression models was verified with the published data of one researcher. The findings indicated that these models are accurate enough for estimating the CR of stones. Consequently, the multiple regression models provide practical advantages for estimating the CR and save time and cost during the planning and design of the stone processing factories.

Now a days high strength and high performance concrete are being widely used all over the world. Most applications of high strength concrete have been in high rise buildings, long span bridges and in some special applications in structures. In developed countries, using high strength concrete in structures today would result in both technical and economical advantage. In high strength concrete, it is necessary to reduce the water/cement ratio and which in general increases the cement content. To overcome low workability problem, different kinds of pozzolanic mineral admixtures (fly ash, rice husk ash, metakaoline, etc.and chemical admixtures are used to achieve the required workability.In the present experimental investigation, the mechanical properties of high-strength concrete of grades M40 and M50, at 28 days characteristic strength with different replacement levels of cement with silica fume or micro silica of grade 920-D are considered. Standard cubes (150mm x 150mm x 150mm), standard cylinders (150mm dia x 300mm height) and standard prisms (100mm x 100mm x500mm) were considered in the investigation. In all, 144 specimens were cast with and without silica fume. The mechanical properties viz., compressive strength, flexural strength and splitting tensile strength, and stress-strain characteristics of high strength concrete with various replacement of silica fume viz., 3%, 6%, 9%, 12% and 15%, has been considered. The investigations revealed that the use of waste material like silica fume improved the mechanical properties of high strength concrete witch is otherwise hazardous to the environment and thus may be used as a partial replacement of cement.

Background and Aim: ZOE has been used in different fields of dentistry for many years. A locally produced component (Zoliran) has been recently introduced to the marketwith similar characteristic to the original Zonalin. Because of a lower cost involved to use Zoliran cement and its availability, confirm reliability of its physical properties. This investigation was designed to assess the Compressive strength of Zoliran cement in comparison to Zonalin cement as the standard material. Materials and Methods: Five samples with dimension of 4mmx6mm of each cement were provided and stored in distilled water in 370C±10C for a period of 24 hours. The lowest load of force was registered as the reference to which the sample could be broken by(according to the criteria No: 30 of ANSIIADA). The value of compressive strength was then calculated using the following formula (K =4F/πD2 ). Results: The mean compressive strength of five samples was measuredas: 14.33 Mpa for Zoliran cement and 31.83 Mpa for Zonalin cement. The mean compressive strength of Zonalincement was significantly higher than the mean suggested in ANSl/ADA Specification No.30. The mean compressivestrength of Zoliran cement was also lower than the mean value registered in ANSI/ADA SpecificationNo.30. Conclusion: Compressive strength of Zoliran cement was significantlylower than that of Zonalin cement. Further tests are required to compare the other physical properties of this material before it can be clinically recommended.

Several full porcelain systems are available in the market, among which In - Ceram (Vita Zahnfabrik, Bad Sackingen, Germany), has been introduced to show unique properties including: fine esthetic and high quality strength. In this investigation Flexural Strength of In - Ceram core material has been evaluated by four - point bending test with Instron (Model 1195) machine. Samples were provided in form of ten bars of core material with the dimension of 30 × 6 × 2.5 mm.Results obtained show that the mean value of 538 ± 42 (MPa), of force is required to hit its resistance limit which is higher than similar values in other dental ceramics, within acceptable clinical range.

Concrete is a construction material consisting of cementitious material, fine aggregate, coarse aggregate and water. Now-a-days, the cost of these materials is increasing. We need to look at a way to reduce the cost of building materials especially cement. One of the recent advancement in construction industry is the replacement of cement with waste materials in concrete. This replacement offers cost reduction, energy savings and protection of environment. To achieve the above objective, an attempt has been made to replace cement with waste marble powder (WMP) produced from marble industries. The present investigation aims to study the mechanical and durability properties of high strength concrete (HSC) with cement partially replaced by waste marble powder. Cement has been replaced with marble powder at 0%, 5%, 10%, 15% and 20% in this study. The properties of concrete such as compressive strength, modulus of elasticity and flexural strength were determined. The durability characteristics such as water absorption, acid resistance and rapid chloride permeability were also determined.