The study analyzes the anisotropy effect for ceramic masonry based on experimental tests of samples made of 25 × 12 × 6.5 cm3 solid brick elements with compressive strength fb = 44.1 MPa and cement mortar with compressive strength fm = 10.9 MPa. The samples were loaded in a single plane with a joint angle that varied from the horizontal plane. The load was applied in a vertical direction. The samples were loaded at angles of 90°, 67.5°, 45°, 22.5°, and 0° toward the bed joints. The most unfavourable cases were determined. It was observed that the anisotropy of the masonry significantly influences the load-bearing capacity of the walls depending on the angle of the compressive stresses trajectory. Approximation curves and equations for compressive strength, Young’s modulus, and Poisson’s coefficient were proposed. It was observed that Young’s modulus and Poisson’s ratio will also change depending on the trajectory of compressive stresses as a function of the joint angle. Experimental tests allowed to determine the failure mechanism in prepared specimens. The study allowed to estimate the masonry strength with the load acting at different angles toward the bed joints.

Cracking in non-load-bearing internal partition walls is a serious problem that frequently occurs in new buildings within the short term after putting them into service or even before completion of construction. Sometimes, it is so considerable that it cannot be accepted by the occupiers. The article presents tests of cracking in ceramic walls with a door opening connected in a rigid and flexible way along vertical edges. The first analyzes were conducted using the finite element method (FEM), and afterward, the measurements of deformations and stresses in walls on deflecting floors were performed on a full scale in the actual building structure. The measurements enabled to determine floor deformations leading to cracking of walls and to establish a dependency between the values of tensile stresses within the area of the door opening corners and their location along the length of walls and type of vertical connection with the structure.

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The results of numerical studies of the degree of pinching of hollow-core precast slabs in the stone walls in the environment of the computing system ANSYS are presented. The numerical calculation of the junction of the floor slab joints with the bearing wall was carried out by the finite element method taking into account the contact interaction of the floor slabs with masonry. The theoretical values of the pinch point degree coefficient are compared with the results of physical studies of a fragment of reinforced concrete slab of prestressed multi-core hollow-core forged slabs with platform joints. The difference between the theoretical and experimental values of the degree of pinching did not exceed 12.5. Based on the numerical calculation, the dependences of the coefficient of the degree of pinching from the elastic modulus of the masonry guests and the magnitude of the compression stresses of the load-bearing walls, using which you can calculate the value of the reference bending moments arising in the floor slabs are obtained. It is shown that the coefficient of the degree of pinching K non-linearly increases with an increase in the elastic modulus of masonry bearing walls. In this case, the greatest influence on the values of K has a change in the modulus of elasticity in the range of 1200-6000 MPa. In the case of supporting the slabs on the walls, made of aerated concrete blocks through a monolithic reinforced concrete belt, the value of the coefficient K increases 1.5 times. It has been established that the degree of pinching depends nonlinearly on the level of compressive stresses at the contact of the plate with the wall. At high levels of compression equal to 1-2 MPa, which are characteristic of the walls of the lower floors of multi-storey buildings, the value of the degree of pinching is in the range of 0.65-0.81.Приведены результаты численных исследований коэффициента степени защемления многопустотных железобетонных плит в каменных стенах в среде вычислительного комплекса ANSYS . Численный расчет узла сопряжения плит перекрытия с несущей стеной выполнялся методом конечных элементов с учетом контактного взаимодействия плит перекрытия с каменной кладкой. Выполнено сопоставление теоретических значений коэффициента степени защемления с результатами физических исследований фрагмента железобетонного перекрытия из предварительно напряженных многопустотных плит безопалубочного формования с платформенными стыками. Разница теоретических и экспериментальных значений коэффициента степени защемления не превысила 12,5 . На основании численного расчета получены зависимости значений коэффициента степени защемления от модуля упругости каменной кладки и величины напряжений обжатия несущих стен, с помощью которых можно рассчитать величину опорных изгибающих моментов, возникающих в плитах перекрытия. Показано, что коэффициент степени защемления К нелинейно возрастает с увеличением модуля упругости каменной кладки несущих стен. При этом наибольшее влияние на значения К оказывает изменение модуля упругости в диапазоне 12006000 МПа. В случае опирания плит перекрытия на стены, выполненные из ячеистобетонных блоков, через монолитный железобетонный пояс значение коэффициента К возрастает в 1,5 раза. Установлено, что коэффициент степени защемления нелинейно зависит от уровня сжимающих напряжений по контакту плиты со стеной. При высоких уровнях обжатия, равных 12 МПа, которые характерны для стен нижних этажей многоэтажных зданий, значение коэффициента степени защемления находится в диапазоне 0,650,81.