1001页：A014 消防建筑施工：建筑基本常识-中国救援装备网

建筑消防常识A14

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My client thanks you for saving his life. However, your well educated, split second, heroic actions caused him under discomfort and harm-Thus...

我的客户感谢你能救他一命。但是，你神乎其技、神勇无敌、神兵天降般的行动伤害到了他，并使他感到不适。因此~~

Lawsuit

诉讼

双语：

Dead Loads

恒荷载

Dead load is the weight of the building itself and any equipment permanently attached to it or built in.

恒荷载是建筑物自身重量和永久附加其上以及内建的物体重量总和。

A more accurate term is self-weight. Years ago, dead load was often piled on the building without regard for the consequences.

更准确地说—自重。以前人们总是在建筑物上不断增加恒荷载，但从不考虑可能的后果。

The modern designer more clearly understands that dead weight breeds dead weight.

当代设计师更清楚，恒荷载需要恒荷载来支撑。

Consequently, efforts are now made to lighten all parts of a building.

因此，现在所有的建筑构件都在向轻量化发展。

Removing a pound of dead weight at the top of a building enables the builder to reduce ounces at many points in the supporting structure.

在最高点拿掉一磅恒荷载，下面很多支撑结构均可减重几盎司。

As proof of the criticality of this consideration, advertisements for building materials such as gypsum shaft liners now emphasize their weight saving over the traditional masonry enclosures.

例子比较极端，但证据比比皆是，像石膏衬板这样的建筑材料在打广告时就会强调其比传统砖砌围墙更加轻盈。

Today, buildings can be considered as being bought “by the pound.”

今天的建筑几乎可以“按斤卖”了。

Fire resistance is closely related to mass.

防火性能与重量密切相关。

All other things being equal, a heavier steel beam will take longer to fail due to heating than a lighter beam.

若其他条件相同，更重的钢梁受热后的坍塌时间点要晚于轻质钢梁。

A 4- by 10-inch (102- by 254mm) wooden beam will support its load longer while burning than will a 2- by 10-inch (51- by 254-mm) beam.

4*10英寸（102*254毫米）的木梁在燃烧状态下比2*10英寸（51*254毫米）坚持更久。

This point highlights a valid general principle: Any substitute structural element that is of less mass than the element previously used to carry an equivalent load is inherently less fire resistant.

这点告诉我们一个常理：承载相同的荷载，更轻的构件防火性能较差。

Added Dead Loads

额外的恒荷载

A structure’s dead load is often increased during alteration of a building.

建筑在改建过程中，通常都会增加恒荷载。

For example, the addition of air conditioners to the roof of a building previously without air conditioning may mean that its dead load is increased without any strengthening of the structure.

例如，给没有空调的建筑添置空调可能意味着在没有增强结构强度的前提下增加了建筑的恒荷载。

At one fire in a large city, fire fighters were overhauling a fire in a restaurant, seeking out hidden pockets of fire in the overhead.

在某市一场餐馆火灾中，消防员在天花板夹层中搜寻火点。

They attacked the fire-weakened supports of the building. Above them, added-on air-conditioning units fell, causing several fatalities.

他们戳到了已经被大火削弱的支撑构件，随后屋顶上后装的空调机掉落，导致数人殉职。

Even when a structure is strengthened to cope with the added load, the modifications may not prove adequate to avoid collapse in a fire.

即使为应对荷载增加而加固过的构件，也有可能在火灾中发生坍塌。

For instance, if lightweight trusses are strengthened by additional trusses, there is no improvement to resistance from fire collapse because all the trusses will burn and lose strength at the same time.

例如，轻质（木）桁架即便经过结构加固，但因为没有针对性提高防火性能，火灾仍能导致其燃烧并坍塌。

In one case, a supermarket was converted to a Japanese restaurant with many grills.

有这么个案例，一家日料店由超市改建而成，内部增设了很多烤炉。

Each grill required a heavy fume hood. These hoods were hung from the roof.

每个烤炉都设置了一个集烟罩，直接挂在天花板下。

When the building was a supermarket, the roof did not have to support such a dead load. Now the same roof must carry the hoods—and safety has been greatly reduced.

之前的超市天花板并不需要承受这些恒荷载，但现在多了这么多罩子以后，安全性必然大大降低。

Dead loads can be deadly—especially dead loads for which the building has not been designed.

那些设计之初并未计入的恒荷载尤为致命。

It is critical that your local building department be notified and that a structural engineer assess the situation when you suspect a dead load is a catastrophe waiting to happen or you see dead loads on a building.

当你看到或感到某些建筑上附加的恒荷载可能会产生灾难性后果时，请务必通知当地的建筑部门并请结构工程师对这些问题进行评估。

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