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.

This paper investigates the mechanical performance of longitudinally cracked glulam columns under eccentric compressionloads. Experimental investigation was conducted to explore the influence of initial cracks on the failure modes and loadbearing capacity of glulam columns. Two different crack patterns named DC and IC, and two column lengths (i. e. 600 and1100 mm) were considered in the experiments. It was indicated that these two crack patterns reduced the capacity of slenderglulam columns and the difference of failure modes was observed between glulam columns with and without initial cracks. Further, a numerical model was developed and validated by the test results. With the application of cohesive zone materialmodel, the propagation of initial cracks could be considered in the numerical modeling. A parametric study was carried outby the verified model and the influence of crack lengths and crack locations was further investigated. From the numericalanalysis, it was found that through cracks reduced the capacity of glulam columns significantly. Also, crack location impactsthe capacity of glulam columns and the extent of impact relates to the slenderness ratio of the columns, while cracks withdifferent lengths have similar influence on the capacity of columns.

For load-bearing mineral wool insulations, compressive stress at 10% deformation is an important property which is studied as a function of density. The determination of compressive behavior of insulations is not a simple and fast test procedure. However, it can be estimated with indirect test method of determination of density which is simple and fast.For indirect test of σ10, it is necessary to find the relations of σ10 and ρ for estimation of mechanical behavior of mineral wool insulations without testing or testing them once in a while. Here, the wool structure, organic content, aging effects on compressive stress for glass wool, rock wool and slag wool are investigated.

The buckling and postbuckling behaviors of a composite beam with single delamination are investigated. A three-dimensional finite element model using the commercial code ANSYS is employed for this purpose. The finite elements analyses have been performed using a linear buckling model based on the solution of the eigenvalues problem, and a non-linear one based on an incremental-iterative method. The large displacements have been taken into account in the nonlinear analysis. Instead of contact elements a new delamination closure device using rigid compression-only beam elements is developed. Effect of delamination length, position through thickness and stacking sequence of the plies on the buckling and postbuckling of laminates is investigated. It has been found that significant decreases occur in the critical buckling loads after a certain value of the delamination length. The position of delamination and the fiber orientation also affect these loads.

Cold metal forming has received considerable attention in recent years. Considering that in most metal forming processes, there exists a compressive stress state, the study of deformation behavior of metals under this condition is of great importance. In this study, the cold upset of aluminum and brass solid cylindrical specimens with different aspect ratios (1.5, 1.0 and 0.5) under different frictional conditions has been investigated. The upsetting tests have been carried out at two different strain rates of 10-2 and 10-3 s-1 and under lubricated and unlubricated conditions. Using PTFE lubricant sheets decreases the friction and thus eliminates barreling phenomenon. In both of the materials under unlubricated condition, decreasing the aspect ratios decreases the stress required for deformation at a constant strain while in the lubricated condition, the behavior is reversed. Using the difference between the stress–strain curves in the lubricated and unlubricated conditions, the contribution of friction and redundant work to the deformation has been studied. For brass, the curves for the stress differences are closer to each other. This may be caused by the presence of undissolved lead in the brass specimens which act as an internal lubricant, causing a lower friction level and thus, a lesser difference between the curves. The calculated friction coefficients were found to have constant values of 0.15 and 0.08 for aluminum and brass, respectively. These values were independent of strain rate and aspect ratio. It has been also found that the value of this coefficient for brass specimens is lower than that of aluminum. It has been observed that change of strain rate does not affect the stress– strain curves for both aluminum and brass specimens.

Use of scrap tire rubber particles as aggregate in Portland-cement concrete is a suitable solution for the environmental hazards of waste tires being produced on a large scale. Tire rubber particles also reduce the brittle behavior of concrete due to their elasticity and plasticity. The effect of tire rubber particles on the mechanical properties of concrete is investigated in this study. Tire rubber particles were used in three (coarse, fine, and combined) groups to replace 12.5, 25, 37.5, and 50% of total aggregate volume in concrete. Cylindrical concrete specimens (15cm across and 30 cm high) were fabricated and cured. A compressive strain-control test was performed on the specimens until failure occurred in large deformations. Results show lower strength and more ductile behavior for rubberized concrete compared to plain concrete specimens. Unlike in plain concrete, the failure state in rubberized concrete occurred gently and uniformly and did not cause any separation in the specimen. The crack width and its propagation velocity in rubberized concrete were lower than those in plain concrete.

Masonry buildings are the most utilized structural system worldwide due to the ease of construction and cost-effectiveness. The effective design of masonry structures has been always an important research subject. Experimental studies are the main component of such research studies. The budget and equipment limitations may challenge the laboratory testing of full-scale masonry specimens and test structures. As such, the use of model-scale specimens may be found as a promising alternative to study the response behavior of this type of structure. In this paper, the stress-strain behavior of half-scale concrete masonry units and prisms (hollow and fully grouted) under compressive loads is evaluated and compared with their full-scale counterparts. The half-scale specimens are standard in that the principles of similitude law have been followed precisely in their aggregate grading, mix-design, physical dimensions, and loading. The stress-strain diagram and failure modes of the half-scale are similar to those of the full-scale. The ratio of half-scale to the full-scale compressive strength of the hollow and grouted masonry prisms on average was found to be 1. 07, and 1. 08, respectively. The experimentally-evaluated response of the standard half-scale specimens that fully satisfy the requirements of similitude law may be extended with good accuracy to the full-scale masonry.

Expanded polystyrene (EPS) is a rigid cellular plastic material with an air-filled closed cellular structure manufactured by moulding beads or granules of expandable polystyrene or one of its copolymers. EPS is a good thermal insulator and is therefore often used as thermal insulation materials in buildings. One of the most important factors in selecting thermal insulation products for building applications is thermal conductivity. Other important parameters are water vapour transmission properties, water absorption, and mechanical properties including compressive stress at 10% deformation, etc. Determination of some of these properties is a difficult task and time-consuming. Density determination is a simple, fast, and inexpensive procedure. Once a relationship between these properties and density was established experimentally, measuring the density-related value of some of these properties can be estimated with a good approximation. In this paper, the relationship between compressive stress at 10% deformation and thermal conductivity with the density of expanded polystyrene (EPS) is studied. Tests for determination of density, thermal conductivity, and compressive stress at 10% deformation of domestic EPS panels were conducted on 209 samples. Experimental results showed that thermal conductivity decreases non-linearly with increasing EPS density. On the other hand, compressive stress at 10% deformation increases linearly with the increase of EPS density.