Concrete-filled composite elements have recently gained popularity as beams and columns all over the world. They have advantages similar to reinforced concrete elements, such as the moulding process and the lack of maintenance of the filled concrete, as well as advantages similar to hollow steel elements, such as enhancing compressive strength and bending capacity by using smaller sections. In this paper, the buckling behaviour of thin-walled steel columns with circular cross-section and different filling materials was investigated under uniaxial load. Six different materials (concrete produced using normal aggregate, concrete produced using waste aggregate, waste fine aggregate, waste coarse aggregate, waste iron dust and polyurethane) were used as filling. Filled columns were compared experimentally with hollow thin-walled steel columns that had the same height and diameter. All specimens had the same length (750 mm), same diameter (60.3mm) and the same wall thickness (3mm). Experimental results were compared with analytical results obtained from a calculation done using the national steel design code, Design, Calculation and Construction Principles of Steel Structures 2016. Additionally, columns specimens were modelled in Abaqus software. Conservative and consistent results were obtained from comparing experimental, analytical, and numerical results.

This study discusses the experimental assessment of the in-plane mechanical behavior of a multi-leaf stone masonry wall built from cut stone and reinforced with metal connectors (cramps and dowels). Inspired by conventional multi-leaf stone walls, the wall is meant for use in modern stone masonry buildings. The wall is constructed from two parallel load-bearing walls with a cavity between them, which aims to conceal the installation and insulation needed in modern buildings. The load-bearing walls are connected with cramps and dowels at certain intervals, so the wall works as a single section against horizontal and vertical loads. To characterize the in-plane behavior of the proposed wall, compressive, triplet, and diagonal compression tests were conducted to investigate the compressive strength, shear strength, modulus of elasticity, stiffness, ductility, and energy absorption of the wall. Compared with dry and mortar joint walls, dowels increased the wall’s initial shear capacity by 11 and 19 times, respectively. Applying cramps without curving channels inside the individual stone elements decreased the compressive strength by 18%. The energy absorption of the designed walls with metal connectors was substantially increased to that of the specimens representing conventional stone walls. The results show the wall’s applicability due to its higher shear strength and minimal drop in compressive strength, which is within acceptable limits.

One of the biggest problems of using public spaces for constructions, such as high-rise buildings, offices, hospitals, and hotels, is noise caused by sound transmission through the lightweight partition walls used to divide volumes. In this study, experiments were carried out to determine the sound transmission coefficient of lightweight gypsum partition walls insulated by CelluBor. Experiments were performed in an anechoic test chamber consists of two separate cells. One cell was used as the sound source, and the other one was used as the receiver cell. A total of 12 samples were used in the experimental studies, which were categorized into four separate groups. The main features that distinguished these groups from each other were the profile height used in the samples and the number of gypsum board layers used on each side of the profiles. In addition, one blank (no insulation) sample, one half filled, and one fully filled with insulation material were used for each test group. The test samples were placed between two cells. The sound volume of the sound source was measured separately in dB in both cells, and the sound transmission coefficients of 12 different samples were determined. It was observed that the most efficient results were obtained only when half of the profile height was filled with the CelluBor material. The use of a composite material consists of boron and waste materials such as CelluBor as sound insulation material in lightweight partition walls can affect the sound transmission coefficient greatly.

This study discusses the experimental assessment of the in-plane mechanical behavior of a multi-leaf stone masonry wall built from cut stone and reinforced with metal connectors (cramps and dowels). The wall, inspired by conventional multi-leaf stone walls, is meant for use in modern stone masonry buildings. The wall is constructed from two parallel load-bearing walls with a cavity between them, which aims to conceal the installation and insulation needed in modern buildings. The load-bearing walls are connected with cramps and dowels at certain intervals so that the wall works as a single section against horizontal and vertical loads. To characterize the in-plane behavior of the proposed wall, compressive, triplet, and diagonal compression tests were conducted to investigate the compressive strength, shear strength, modulus of elasticity, stiffness, ductility, and energy absorption of the wall. Compared with dry and mortar joint walls, the use of dowels increased the initial shear capacity of the wall by 11 and 19 times, respectively. The application of cramps without curving channels inside the individual stone elements decreased the compressive strength by 18%. The energy absorption of the designed walls with metal connectors was substantially increased to that of the specimens representing conventional stone walls. The results obtained show the applicability of the wall due to its higher shear strength and minimal drop in compressive strength, which is within acceptable limits.