A bridge has a sign which states a load capacity of 30 tons, how come a truck loaded with a 60 ton cargo was able to pass through without the bridge collapsing?
I live near Marlow in the UK which has a suspension bridge over the river Thames.The bridge was designed and build in 1830 by William Clark as a prototype for a bridge over the Danube in Budapest, so it may look slightly familiar.The Marlow bridge has a vehicle weight limit of 3 tonnes.Last year a truck driver managed to drive a 30-tonne truck most of the way across the bridge before he burst his tyres on the width restriction bollards on the opposite side.The bridge was closed for two months whilst all the structural components were inspected - no significant damage was found and the bridge was reopened.There are a couple of reasons why an apparent safety factor of at least 10 applies on this bridge:The bridge is constructed from timber, stone and wrought iron which have less predictable properties than modern materials, so multiple conservative safety factors will have been applied by the engineers assessing it.A single 30-tonne load event is not the same as continuous repeated 30-tonne load events which would have a significant fatigue effect on the structural components.So engineers are not only looking at the bridge’s ability to sustain a single load event, but are looking at the overall design life of the bridge. This could represent the difference between a design life of 3 months and a life of 25 years depending on the traffic flow.
Why do they close lanes on the Bay Bridge at night?
It's done for maintenance of the bridge: painting, mostly. The salty marine air is very corrosive and bridge surfaces must be continually repainted to protect the metal. In the early nineties it was done during the day, closing two eastbound lanes during commute times.
Would being able to conduct bridge inspections without closing the bridge be advantageous to your company?
Obviously.The inspection of bridges is normally highly disruptive to traffic. Lane closures and overnight closures are routine, and a diversion route would normally have to be planned. These can have a profound impact on traffic on major bridges, such as the Forth Bridge.[1]I’m not quite sure if your question is some kind of promotion for your company, but as a general point of interest, it appears that drone inspections are particularly popular for rapidly speeding up the inspection of bridges and other large-scale infrastructure projects.The idea is that the drone can take hundreds of thousands of images of the structure (possibly for photogammetry), and engineers can use the information to find areas of deterioration which should be inspected up close. This does not eliminate the human element, it just saves time because inspectors can be sent to the areas that require further survey.Arup identified drones for maintenance as part of its Future of Rail 2050 report.[2]Footnotes[1] Forth bridge work fast-tracked to ease traffic woe[2] Future of Rail 2050
Why has the bridge scandal hurt Chris Christie's presidential chances more than Benghazi and the email scandal have hurt Hillary's?
Because the 'scandals' in question have no comparison. Benghazi is a scandal only if you're a conservative who really needs a scandal. Don't believe me? Then find me a non-partisan or Democratic expert who really thinks this is a major scandal? Benghazi is a political battle, not a genuine scandal. The email scandal has more weight to it, but far less interest. She deleted emails? Okay, is that something I should get enraged about? Is that something that shouldn't have happened? Is it common practice? Is it illegal? Does it point to something more sinister? The legal and ethical points of document retention policy just don't rile up the average person that much. What she did may have been wrong, but the damage is so theoretical it kind of falls flat for most people. The bridge scandal, on the other hand is obvious and visceral. Deliberately creating traffic jams in one of the busiest areas in the world? And doing it for political revenge? That's both viscerally troubling (anyone who's ever been stuck in traffic can get mad about that) and unbelievably petty and bullying. The reasons for it are almost worse than what was actually done. You're angry that someone didn't endorse you in an election that you won anyway, so you make people in his area sit in traffic? That suggests a level of both malice and insecurity that are terrifying in a leader. Even if we assume that Christie had nothing to do with it, he's built a team and culture in his administration where this would both happen and be freely joked about. That speaks pretty badly as to the kind of leader he is. Unlike Benghazi, there's evidence of actual wrongdoing. Unlike the emails, there's something here that most people actually care about. It's hardly surpising that the public would take notice.
Driving from central Illinois to Six Flags near St. Louis?
Your best bet would be to take 70 or 64 to 255 South. Cross over into Missouri over the Jefferson Barracks Bridge and 255 will actually change into 270 north (by staying on the same highway) as it curves around the south side of the St. Louis area. You'll take Highway 44 (I believe it is exit 5b (not positive though) west towards Fenton/Valley Park (The sign might say towards Springfield). You'll follow that for about 10-15 minutes and you'll see exits for Eureka. Stay on that highway just past the initial Eureka exit to the actual "Six Flags" exit (you'll have passed by Six Flags on the right). Just be careful---during the summer some people forget that there are dedicated exit lanes and drive like idiots. Have fun!!!
Hazards on when crossing the border?
Check your drivers manual. Your hazard lights should be used when you are in a lane of travel and not moving or moving slowly. This is a courtesy to people behind so they do not hit you. You DO NOT have to turn them on. It is just a safe driving thing. You are stopped on the road or at the side of the road. If your vehicle is disabled, or you absolutely have to stop on the shoulder for some reason, activate your hazard lights. You are travelling signficantly below the speed limit. If you are travelling below the speed limit by 20 km/h or more, you may want to activate your four-way flashers to warn traffic behind you. Naturally, there should be some reason you are travelling this slowly. Visibility is seriously degraded in bad weather. This is related to #2. If you're driving in heavy rain, snow, or fog and are travelling more slowly than normal, you can activate your hazard lights. Your full vehicle lighting (headlights and tail-lights) must also be activated as required by Section 62(1) of the Ontario Highway Traffic Act. The on-and-off flashing of the hazard lights may be more visible to some drivers than the steady light from other vehicle lighting. Of course, you really shouldn't be driving in these conditions if possible. Traffic is slow or stopped ahead of you. You can use your four-way flashers to warn traffic behind you. This is relatively uncommon in the US and Canada. Many people choose to briefly activate their brake lights instead, however this is more easily missed if drivers behind you look away for a moment. http://ontariorulesoftheroad.blogspot.ca...
What is a fig tree? and why do people keep using it as a idiom?
Fig Tree or The Fig Tree may refer to ficus, a genus of about 850 species of woody trees, shrubs, vines, epiphytes, and hemiepiphyte in the family Moraceae, collectively known as fig trees or figs. It may also refer to: Charybdis Fig Tree, a mythological fig tree in Homer's Odyssey Fig Tree, an imprint of Penguin Books Fig Tree Bridge, girder bridge that spans the Lane Cove River Fig Tree Pocket, Queensland, a suburb of Brisbane, Australia "Under the fig tree" became an idiom for one who sits under the shade of a Rabbi's teaching enjoying the "sweet" fruit of his instruction and wisdom. “And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together and made themselves aprons.” (Genesis 3: 7) Adam and Eve The fig tree was to have significance in the teaching of the nation of Israel about their destiny and God's purpose on earth. “Judah and Israel dwelt safely, every man under his vine and fig tree.” (1 Kings 4: 25) A vision of security and safety is also created by Micah in describing the 'last days'. “They shall sit every man under his vine and under his fig tree; and none shall make them afraid.” (Micah 4: 4) In a dried state, the fig was an article of commerce and a staple food. In the case of Hezekiah, the fig was used for medicinal purposes. If the fig trees failed to produce, it constituted a national calamity. Their productiveness was a token of divine favour, of peace, prosperity and security. The Messiah spoke a parable related to the fig tree which is recorded in Luke 13: 6-9. “A certain man had a fig tree planted in his vineyard; and he came and sought fruit thereon, and found none. Then he said to the dresser of his vineyard, Behold these three years I come seeking fruit on this fig tree, and find none: cut it down: why cumbers it the ground? And he answering said to him, Lord let it alone this year also, till I shall dig about it, and dung it: and if it bear fruit, well: and if not, then after that thou shall cut it down.” (Luke 13: 6-9) Undeniably this fig tree represented Israel. This parable was given in the closing days of the third year of the Messiah's ministry. It was autumn A.D 29. In the spring of the following year was the crucifixion. For three years the Jews had had the opportunity to recognise and acknowledge their Messiah.