Effects of Layered Accretion on the Mechanics of Masonry Structures
Effects of Layered Accretion on the Mechanics of Masonry Structures
复制标题
层状增生对砌体结构力学的影响
DOI：
10.1080/15397734.2011.628622
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发表时间：
2012
影响因子：
3.9
通讯作者：
L. Gambarotta
中科院分区：
文献类型：
--
作者：
A. Bacigalupo;L. Gambarotta
砖混结构是在连续的砖层或砌块中建造的，当这些结构处于静力不确定和重力荷载占主导地位时，这可能会对这些结构的变形和平衡产生相当大的影响。这个问题是通过参考厚拱在无应力条件下通过连续沉积重砖层而达到最终形状的方式来分析的。与结构尺寸相比，吸积层的砖/块单元的大小被假定为可以忽略不计，并考虑到它们在沉积瞬间可能在当前的外壳体上滑动，从而描述了所产生的连续沉积。成长体的运动学描述为在考虑的点上，当它附着在当前的外延上，即在吸积层上时，由于不断增加重层而产生的位移与初始位移的叠加。对应的两个应变张量场不满足协调方程，而总应变场则相容。应力场是在具有残余应力的生长过程中由附加层的重量引起的增量应力的累积效应，它与初始应变场无关。分析了生长过程对应力场的影响，并讨论了应变场的性质。第一个例子涉及在周期性点处支撑的砖墙，而第二个例子涉及分段多叶厚拱门，其中生长过程从一个依靠自身重量的细拱门开始。在这两种情况下，与在最终区域施加重力载荷的解相比，观察到应力场显着增加。
Masonry constructions are built up in successive layers of bricks or blocks that may have considerable effect on the deformation and equilibrium of these structures when they are statically indeterminate and when gravity loads are predominant. This problem is analyzed by referring to a thick arch that reaches its final shape by means of a continuous deposition of heavy brick layers in stress free condition. The brick/block units of the accreting layer are assumed to have a negligible size in comparison to the structural size and the resulting continuous deposition is described taking into account their possible sliding on the current extrados at the instant of deposition. The kinematics of the growing body is described by the superposition of the displacement resulting from the continuing addition of heavy layers to the initial displacement at the considered point when it is attached to the current extrados, i.e., on the accreting layer. The two corresponding strain tensor fields do not satisfy the equations of compatibility, while the total strain field results to be compatible. The stress field is the cumulative effect of the incremental stress induced by the weight of the added layers during the growing process with residual stresses, which are shown to be independent of the initial strain field. Two examples are analyzed to show the effects of the growing process on the stress field and the properties of the strain field are discussed. The first example concerns a masonry wall supported at periodic points while the second example concerns a segmental multileaf thick arch in which the growing process begins from a thin arch resting on its own weight. In both cases a remarkable increase of the stress field is observed in comparison to the solution where the gravity loads are applied on the final domain.