71土木专业英语Masonry Properties.pptVIP

7.1 Masonry Properties Masonry is typically site constructed using manufactured masonry units砌块 and site mixed mortar. The units are laid in mortar to various heights, with the strength of the assembly being achieved during curing of the mortar. Masonry is normally used for components subjected to compressive loading. Masonry walls also have a limited capacity to support horizontal loads and bending moments. Masonry Materials Masonry Units clay units粘土砖 ≥MU10 hollow (cores occupy greater than 25% of unit) Perforated [5pE:fEreit] adj. 多孔的 solid concrete units混凝土砌块 ( solid or hollow) stone units calcium silicate units硅酸盐砌块砌体 Masonry Materials Mortar composed of cement, lime [laim] 石灰 and sand bond masonry units together to form a composite structural material. is a factor in the compressive, shear, and flexural strengths of the masonry assemblage compensates for dimensional and surface variations of masonry units resists water and air penetration through masonry bonds to metal ties, anchors, and joint reinforcement so that they perform integrally with the masonry units. Mechanical Properties--Compressive Strength masonry loaded in uniform compression fail by the development of tensile splitting cracks parallel to the axis of loading The tensile stresses which cause the splitting type of failure result from the restrained deformation of the mortar in the bed joints of the masonry Mechanical Properties--Compressive Strength strength of masonry in compression is smaller than the nominal compressive strength of the units masonry strength may greatly exceed the cube compressive strength of the mortar used in it. Mechanical Properties--Compressive Strength The mean compressive strength of plain masonry made with general purpose mortar may be calculated on the basis of mean compressive strength of masonry units and compressive strength of mortar: Mechanical Properties--Shear Strength Two forms of shear strength exist tension shear sliding Failure modes of