土木工程专业英语
土木工程专业英语结课作业 姓名:朱枭杰 班级:1218342 学号:012301834241 Architecture in a Climate of Change Low energy techniques for housing It would appear that,for the industrialised countries,the best ch ance of rescue lies with the built environment because buildings in use or in the course of erection are the biggest single indirect sour ce of carbon emissions generated by burning fossil fuels,accountin g for over 50 per cent of total emissions.If you add the transport co sts generated by buildings the UK government estimate is 75 per c ent.lt is the built environment which is the sector that can most eas ily accommodate fairly rapid change without pain.In fact,upgrading buildings, especially the lower end of the housing stock,creates a c luster of interlocking virtuous circles. Construction systems Having considered the challenge presented by global warming and the opportunities to generate fossil-free energy,it is now time t o consider how the demand side of the energy equation can respo nd to that challenge.The built environment is the greatest sectoral consumer of energy and,within that sector,housing is in pole positi on accounting for 28 per cent of all UK carbon dioxide (CO2) emis sions. In the UK housing has traditionally been of masonry and since the early 1920s this has largely been of cavity construction.The pu rpose was to ensure that a saturated external leaf would have no p hysical contact with the inner leaf apart from wall ties and that wate r would be discharged through weep holes at the damp-proof cour se level.Since the introduction of thermal regulations,initially deem ed necessary to conserve energy rather than the planet,it has be en common practice to introduce insulation into the cavity.For a Ion g time it was mandatory to preserve a space within the cavity and a long rearguard battle was fought by the traditionalists to preserve this sacred space .Defeat was finally conceded when some extensive r esearch by the Building Research Establishment found that there was no greater risk of damp penetration with filled cavities and in f act damp through condensation was reduced. Passive solar design can be divided into three broad catego ries: • direct gain; • indirect gain; • attached sunspace or conservatory. Each of the three categories relies in a different way on the “greenhouse effect as a means of absorbing and retaining heat.Th e greenhouse effect in buildings is that process which is mimicked by global environmental warming.In buildings,the incident solar rad iation is transmitted by facade glazing to the interior where it is abs orbed by the internal surfaces causing warming.However,re-emissi on of heat back through the glazing is blocked by the fact that the r adiation is of a much longer wavelength than the incoming radiatio n.This is because the re-emission is from surfaces at a much lower temperature and the glazing reflects back such radiation to the int erior. Direct gain Direct gain is the design technique in which