我的巨大
发表于 2025-3-23 09:58:32
Soft materials and living structures — ospered for long naked and unconfined. At the time this planet presumably afforded rocks and sand, water and an atmosphere of sorts, but it must have been rather short of suitable materials for containers. Hard shells could be made from minerals, but the advantages of a soft skin, particularly in th
progestin
发表于 2025-3-23 15:09:43
Walls, arches and dams — nd treacherous traps for the unwary. This is especially the case when we want to make a structure from more than one piece of material, so that we are faced with the problem of preventing it from coming apart at the joints. For these reasons our ancestors generally avoided tension structures as far
diskitis
发表于 2025-3-23 19:19:13
Something about bridges — eenth century, it is undoubtedly very much older, and the . devotes several rather gruesome pages to it. All over the world bridge-building used to be associated with children’s dances — . — and with human sacrifices which are not just legends. At least one child’s skeleton has been discovered immur
helper-T-cells
发表于 2025-3-23 23:18:56
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cauda-equina
发表于 2025-3-24 02:21:13
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orient
发表于 2025-3-24 09:28:54
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预感
发表于 2025-3-24 11:57:35
The philosophy of design — r one which it is proposed to build, one which is actually in existence but whose safety is in question, or else one which has, rather embarrassingly, already collapsed. In other words, if we know the dimensions of a given structure and the properties of the materials from which it is made, we can a
影响
发表于 2025-3-24 17:47:02
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滑稽
发表于 2025-3-24 22:54:10
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jarring
发表于 2025-3-25 00:08:54
Strain energy and modern fracture mechanics — n algebraical methods, he pointed out that the existence of even a tiny unexpected defect or irregularity in an apparently safe structure would be able to cause an increase of local stress which might be greater than the accepted breaking stress of the material and so might be expected to cause the structure to break prematurely.