“History may not repeat itself, but it does rhyme！” —— Mark Twain

“历史不会重演,但有其韵律!”——马克·吐温

What is sign engineering and does it concern you? In almost any sign fabrication setting, engineering of a kind does concern you, because, whether you’re welding girders or hot-gluing foamboard displays, the way any type of sign structure goes – and stays – together involves several critical factors: an intelligent analysis of all mechanical and stress aspects, proper materials and intelligent completion actions. Therefore, you become a type of mechanical engineer the moment you decide how to join two parts.

什么是标识工程，它的存在和我们的生活有什么关联之处呢？无论您是焊接梁还是热粘合的泡沫板标识，任何一种标识结构的走向和保持的方式都涉及几个关键因素：对所有合适的材料、安装设备和承受力方面的进行智能分析。

• Is the joint or structure load (weight) bearing?

•标识架构能承受的重量是多少? 

• How are the pieces to fit together? 

•如何将各个部分组装在一起? 

• How will you join them?

•你对安装标识有没有相应的计划? 

• Are your chosen materials and joining process tested, and will it endure the various stresses the junction or supporting scheme may encounter? 

•您选择的材料和连接工艺是否经过测试，是否能够承受或支撑标识，是否有遇到的各种风险的应急方案? 

• Does your joining modus align with the job cost projections?

•你的计划是否符合工作成本预测? 

• Can the joining be done in-house or do you need to outsource the process?

•项目可以在公司内部完成，还是需要外包? 

• And, because the signmakers’ task is to make attractive signs, is your joining method undetectable and pleasant to view?

•还有，因为标识制作商的任务是制作吸引人的标识，所以你的设计方案是否存在让人难以察觉、难以欣赏的问题? 

Hopefully, this will remind of the need for engineering-type thinking, even in everyday fabrication and installation operations, especially when you’re in the field and dealing with existing conditions you may not have created or contemplated.

希望这能提醒我们，即使是在日常的制造和安装操作中，也需要具体的计划，特别是当你在现场处理你可能没有遇到或考虑到的突发状况时。 

EXISTING SIGN STRUCTURES

标识结构的安全性

Lately, because I enjoy photographing old structures, I’ve seen and studied some what I’ll call archaic sign installations and couldn’t help but wonder if they have remained safe. With this in mind, I telephoned Sean McFarland of McFarland Engineering (Advance, NC) because his firm handles big-time sign engineering jobs, but he also offers practicality when it comes to everyday sign engineering and installation. McFarland has one of those minds I enjoy being around. Ask him a question and you can almost hear him mentally ticking through complex details before he decides which concept is most relevant for him to present. For example, I asked about old pole signs, because I had recently studied one that appeared more like a salvage-yard find than an able structure. It was dented by car bumpers and speckled with rust, looking more like the surface of an overbaked pizza than a sign pole. Still, it supported three cabinet signs. 

最近，因为我迷上拍摄古老的建筑，我看到并研究了一些我称之为古老的标识装置，不禁想知道它们是否仍然安全。带着这种想法，我给麦克法兰工程公司（McFarland Engineering）的西恩·麦克法兰（Sean McFarland）打了电话，因为他的公司从事大型标识工程的工作，但他也提供日常标识工程和安装。麦克法兰有我喜欢的那种想法。问他一个问题，你几乎可以听到他在脑海中对这个问题诠释的复杂细节，然后他会告诉我关于问题的各种信息。例如，我询问他关于旧标识的问题，因为我最近正在研究一个废品回收厂里发现的标识，那个标识过于古老，它一看就被汽车的保险杠撞过，但它的结构仍然很结实，虽然标识的支撑杆早已锈迹斑斑，锈的仿佛是一个烤糊了的披萨，但它仍然坚强的支撑着三个标识灯箱。

I didn’t park my car underneath it.I asked McFarland, “What should a signshop know before mounting a new sign on an old pole structure?” 

以防万一我没有把车停在旧标识的下面，我问麦克法兰:“在旧的标识结构上安装新标识之前，标识店应该注意些什么?”

I swear I heard his mind clicking. He said to look for an access – inspection– hole in the pipe, and, if you can see inside, try to determine if the pole has ever held standing water that could cause excessive interior rust. There are sensor devices that measure rust damage, but visual indications of pitted steel or flaking could be serious warnings that, say, the original pipe wall thickness is now considerably lessened. 

麦克法兰说：“首先你需要在标识的支撑杆上找一个检修孔，如果你能看到里面，试着确定支撑标识的杆里是否有积水，因为积水可能导致内部生锈。有一些传感设备可以测量锈损，但如果结构出现严重的锈斑和表面脱落的现象就需要重视，原来的管壁厚度现在已大幅减少，所以一定要做好安全检查工作。 ”

McFarland explained that pole-sign framework modifications are also indicators of a weakened structure. We’ve all seen such late-in-life modifications – angle-iron tangles – to sign structures. I don’t park underneath these, either.

麦克法兰解释说：“标识结构的修改也是结构弱化的表现，我们都见过这样的标识晚期改造，一般试图用角钢缠结来重新规整标识结构。”

Pole-sign, match-plate modifications are of special concern to McFarland, because modifications here – new plates with unmatched bolt holes, say – can cause the plate to stand offside the original plan and change the torsion factors, which cause new stress dynamics, especially in windy conditions.

对麦克法兰来说，标识的支撑杆、模板的修改尤其重要，比如，带有不匹配螺栓孔的板材，可能会使结果偏离原计划，改变标识的构造，从而导致不同的安全问题，尤其是在有风的情况下标识会更加危险。 

Be cautious also of wall-sign replacements, e.g., replacing same-size wall signs that were installed years ago when zoning codes and weather patterns may have been different, and thinking you can reuse a similar mounting system. Not so. He also cautioned regarding wall-sign installation on brick façades, noting that brick is a veneer and each brick wall has a limited-load capacity, which can be influenced by how often one makes attachments to it. A classic example, he said, is when using a steel plate to mount a blade sign, one with bolt holes that are closely spaced and therefore weaken the brick veneer’s capacity to handle the load. 

同样要小心墙壁标识的更换，例如，更换多年前安装的相同尺寸的墙壁标识，受当地天气的影响，标识的架构会有所损坏，但大多数人都以为能够继续使用同一架构，但事实不是这样的。他还警告说，在砖外墙上安装墙面标识时，注意到砖是贴在建筑物上的，每个砖墙都有有限的承载能力，砖墙可能会受到附着物的影响产生危险。他说，最典型的例子就是使用钢板安装标识，螺栓孔很小，因此会给墙面带来过度的承载力。

GALLOPING SIGNS?

标识的潜在危险性

Proper sign engineering should always be a concern.

如何确保标识工程安全始终是一个问题。 

Benjamin Jones, PE, in his book, Engineering Sign Structures , writes of the many common sign phenomena. Regarding wind, he writes, “Vortex shedding is one example of phenomena loosely called ‘aerodynamics effects.’ Some others are galloping, flutter and aeroelastic effects – the interaction of wind with a moving structure.”

本杰明·琼斯在他的书《标识结构工程》中，写了许多常见的标识现象。关于天气因素——风，他写道：大风导致标识脱落是一个很普遍的现象，暂且称它为“空气动力学效应”， 还有一些是驰振、颤振和气动弹性效应，即风与物体的相互作用。

Sign flutter? You bet. And, like the constant bending of a wire coat hanger to break it, flutter can break a sign-support bolt or bracket. Jones’ book includes a series of sketches that exhibits the action of wind on sign surfaces. They look like untethered ships being tossed about by a Caribbean hurricane. 

受大风天气影响，大风会导致标识整体震颤，从而会发生螺丝松动，标识坠落的现象。本杰明·琼斯的书中有关于受风力影响的标识草图，它们看起来像是被加勒比飓风肆虐的不受限制的船只。

You should have a copy of Jones’book (available from Amazon.com) on your desk, one that’s heavily highlighted and flagged with 3M sticky notes.

你的办公桌上应该放一本琼斯的书(亚马逊网站上有售)，这本书里面涵盖了很全的标识知识。 

Your sign isn’t going outside? It’s a digitally-printed, hot-glued cutout for a retail store? No wind, no worries, right? What about the prosecutions of a bored, six-year-old schoolboy? 

你也可以把你的标识安装在室内显眼的地方，比如零售店里面那些数码印刷的标识，没风，没烦恼。 

MONEY AND SIGN ENGINEERING

标识经济

In his book Sign Structures and Foundations: A Guide for Designers and Estimators , Peter B. Horsley, a founder of modern sign engineering, writes of the economic realities of running a business. In that passage, his primary focus relates to material costs and taxes. 

现代标识工程的创始人彼得·霍斯利(Peter B. Horsley)在他的著作《标识结构与基础:设计师和评估人员指南》(Sign Structures and Foundations: A Guide for Designers and Estimators)中，描述了经营企业的经济现实。在这篇文章中，他主要关注的是材料成本和税收。 

You should have a copy of Horsley’s book (available from Amazon.com) on your desk, too, one that’s also heavily marked.

你的桌子上也应该放一本霍斯利的书，这本书可以帮助你了解标识的经济方面。 

Horsley’s business was in Canada, a more socialistic economy than the US, and thus one with higher taxes. However, an exploration of Horsley’s tax and expense list reveals shop expenses similar to those faced by US signshops – although the percentages might vary. He lists excise tax on imported parts or components, income tax, sales tax, property tax, gasoline tax, business tax, business permits, vehicle license plates, medical tax, worker’s compensation, unemployment insurance, pension plans, corporate tax, auditing expenses, wages for holidays and vacations, and regular operations expenses, e.g., telephone, power, maintenance and more. 

霍斯利在加拿大做生意，那里的经济比美国更社会主义，因此税收更高。然而，对霍斯利的税单和费用清单的研究显示，商店的开支与美国标识店面临的开支类似，尽管比例可能有所不同。他列出了消费税对进口零件、组件、所得税、销售税、物业税、汽油税收、营业税、业务许可证、工资和常规操作费用（电话、电力、标识维护等）。

Horsley introduces cost reminders because he recognizes that any aspect of contracted engineering must fall within the arena of affordable shop expenses, i.e., operating costs, as well as adding to the business profit picture. Thorough engineering can cut costs and lower future risks. Flawed engineering eventually adds to shop costs, especially if a structure failure occurs that causes re-engineering and outlays in fixing, redesigning or reworking the failure. Or, worse, damage and litigation costs.

霍斯利之所以引入成本提醒，是因为他认识到合同工程的任何方面都必须属于可负担得起的车间费用的范畴，即经营成本，以及增加的商业利润。彻底的工程可以降低成本，降低未来的风险。有缺陷的工程最终会增加车间成本，特别是如果发生结构故障导致商家需要重新设计和修复，重新设计和修复故障的费用都需要商家自己承担，如果发生事故还要面临更糟糕的人身损害和诉讼费用。

THE TEN-CENT BOLT

“便宜”的失误

H.W. Morrow says, in his book, Statics and Strengths of Materials , a “structure” comprises a series of connected structural members or rigid bodies that are designed to support loads or forces, and notes that all acting forces (on structures) are applied to the joints, as well as that members, joints and loads lie in a plane. Therefore, stress at one point will, in some way, affect the other structure components. He notes that one must determine the external forces acting on a structure – wind is the big concern with signage – but also the forces that hold the parts together. Bolted material (plates, for example) becomes compressed and correspondingly, the composite material being compressed presses back against the bolt head and nut, which adds tension to both bolt and plates. Thus, sometimes tightening is best measured by a torque device rather than strong-arm actions. Also, tension failures of connecting plates can be caused by holes, fractures or a general yielding of the plates. Shear failure usually befalls bolts or similar fasteners first. 

H.W.莫罗在他的“材料的静力学和强度”一书中说，“结构”由一系列连接的结构构件或刚体组成，这些构件或刚体被设计用来承载荷载或力，并且注意到所有的作用力(在结构上)都施加在接缝上，而构件、接缝和荷载都在一个平面上。就好比所有乘客都在一架飞机上。他指出，必须确定作用在结构上的外力，风是标识的主要关注点，而且还有将部件固定在一起的力。螺栓材料被压缩，相应地，被压缩的复合材料压靠螺栓头和螺母上，这增加了螺栓和板的压力。因此，有时紧固螺栓最好通过相应的工具而不是蛮力去拧。此外，连接板的损坏可能是由孔、裂缝或板的弯曲引起的。剪切破坏通常首先发生在螺栓或类似紧固件上。

In his columns for Road & Track magazine, my friend Allan Girdler once wrote of his brother losing a sports car race due to a ten-cent bolt that broke on the last lap. It’s not an uncommon story, so don’t buy cheap bolts. Girdler, in summation, advised expensive fasteners and close visual inspection of all joined components. 

我的朋友艾伦•格德勒(Allan Girdler)曾在他为《道路与轨道》(Road & Track)杂志撰写的专栏文章中写道，他的哥哥在一场赛车比赛中因最后一圈时一个10美分的螺栓断裂而输掉了比赛。这不是一个罕见的事，所以不要买便宜的螺栓。综上所述，格德勒建议在制造标识时尽可能使用相对结实贵一点的紧固零件，并对所有连接部件进行仔细的检查，以避免不必要的损坏。 

EXPENSIVE GOOFS

昂贵的教训

Many elements must come together to properly engineer a sign.

标识是许多元件组合在一起的结果。 

In The Design of Design , Frederick P. Brooks, Jr. says amateurs make a lot of mistakes that a professional would not, but when they do goof, professionals do it in a big way – making bridges that collapse, houses without stairs between floors, and my favorite, computers that radically waste memory bandwidth, as does my new Lenovo laptop. What the hell is a Mixed Reality Viewer, anyway?

小弗雷德里克·布鲁克斯（Frederick P. Brooks，Jr）从事的标识设计。他说有些专业人士总是批评业余爱好者犯了很多专业人士不会做的错误。但某些专业人士自身也存在很多问题，他们也应该审视自身。比如，桥梁倒塌，标识从高空坠下。这些问题应该被这个行业的人所重视起来。

You can search Google for a recent history of sign failures: Sign falls on car; Potomac Mills sign falls; downtown Atlanta sign [mural] falls off building; Taco Bell sign falls; sign falls on family; and the erstwhile but always notorious Las Vegas Hilton sign collapse.

您可以搜索谷歌来查找最近的标识失败历史：标识落在汽车上，波托马克市米尔斯标识倒塌；亚特兰大市中心的标识从建筑物上脱落；塔可钟标识倒下；标识落在行人身上；而昔日声名狼藉的拉斯维加斯希尔顿酒店的标识也轰然倒塌。

The worst recent engineering failure relates to the Florida Intl. Univ. and City of Sweetwater’s 174-ft.-wide, 950-ton pedestrian bridge installed across eight lanes of Tamiami Trail. You saw it on the news. Due to engineering wants, it fell onto the roadway and crushed eight cars, killing six people. This happened March 15, only a few days after the pre-fabricated bridge section had been installed. 

最近最严重的工程事故与佛罗里达国际机场有关。斯威特沃特市的174英尺宽，950吨的人行桥安装在塔米米小道的八条车道上。新闻报道这座大桥塌在路上，压碎了8辆汽车，造成6人死亡。这就发生3月15日，在预制桥梁部分安装后的几天。 

Outside expert reports say that a particular truss member was “underdesigned” and not strong enough to withstand the pressure from the weight of the bridge. True? I have no idea, but you can be sure the cause will be contested for years.Frankly, I’d rather design and build signs than sit in court. You?

有关专家报告说，是桥梁的内部结构存在“设计漏洞”，内部结构不足以承受桥梁的重量。但关于桥梁倒塌的原因这几年也有所争议。所以无论是建造大桥还是标识，安全问题永远是第一位的，制造者应该把关每一个细节，这既是对消费者的负责，也是为自己的负责。