cladking Posted May 4, 2014 #101 Share Posted May 4, 2014 Do you imagine, then, a gang pulling on a stone with some workers directly in front and some (slightly) to one side, but not the other side? There are several ways they could have dragged stones and counteracted this force. These countermeasures come almost automatically when you are dragging something and it goes the wrong way. Like driving a car you simply correct or redirect the forces. In many situations you aren't even aware you are compensating for these forces. It's not the inability to correct for the sideways forces that concern me as much as it is an unsteady and uneven pull of a sled perched precariously on wet sand that might be more like mud than sand. I'm not convinced even the hardest sand could support a pyramid stone with a nice even pull much less that the sand that was at Giza could support a sled being brutishly dragged along by men. Using far more men than needed would help somewhat since they could develop a nice steady gait. 1 Link to comment Share on other sites More sharing options...
scorpiosonic Posted May 4, 2014 #102 Share Posted May 4, 2014 (edited) Obviously the technique worked for the AE on AE sand as the wall painting clearly depicts.... The AE knew how to drag lg statues on sledges across the desert sands, and knew how much water to use... they didn't use dogs, but I'm sure their dogs knew more about engineering 101 than you do CK. Your refusal to accept the clearly presented evidence is just the SOS. . I don't believe that what's a Giza is really sand at all. It's not "sand" now and it wasn't when the pyramids were built. It's extremely "dirty" sand mixed with all sorts of particulate matter in a wide range of sizes. "Sand" is a specific type of stone segregated into a narrow spectrum of sizes by wind or water (usually). Very small material and dusts will change the nature of the "sand" when it gets wet. It will tend to make it turn into mud rather than a hard surface like wet sand. "Mud" can be as much as about 60% sand in my experience. What YOU believe is irrelevant, as I've stated previously, the AE knew how to drag sledges across the Egyptian desert, and did so efficiently. IF you can't accept this reality, it's your problem. You are waffling, they pulled these sledges over extremely varied conditions, inc. @ the Giza Plateau. No. Reality is different. One gets a good purchase in sand. The difficulty of walking in loose sand is that your foot sinks in and you have to lift your whole body up out of the hole you just made. It's like trying to walk up a ramp. The deeper you sink in the steeper the ramp. In my reality very soft sand is much harder to walk on, etc.(it's harder to lift your FOOT out, and you lose TRACTION) and hard ground is easier....but I'm not sure about the sand on your planet. (The stone lined ramp has been mentioned here several times, no sinking, no chance in angle of incline, get real. ) Only a fool builds a ramp of sand. Edited May 4, 2014 by scorpiosonic 2 Link to comment Share on other sites More sharing options...
cormac mac airt Posted May 4, 2014 #103 Share Posted May 4, 2014 OK thanks for the input, so we can agree then a drought took place after the mids erection, so before this time, no drought to speak of and fertile land once again? I hope you see what Im trying to get at here, desertification took greater place following the drought... thus creating the dusty sandy environment which eventually buried many structures, like the Spynx for example No significant drought in any case and the land would have been greener and wetter than now. I get the gist of what you're trying to say. But remember that the area of the quarries, located to the south/east of the Gizamids, was already on top of the Giza Plateau which itself is limestone. The Egyptians would have only needed to clear a pathway of sand down to the limestone 'floor' in order to move blocks. It's not like they were moving blocks through sand-dunes. cormac 2 Link to comment Share on other sites More sharing options...
029b10 Posted May 4, 2014 #104 Share Posted May 4, 2014 (edited) Well, thanks for you unqualified input, which shows that you know nothing about the subject matter. If you have the desperate need to believe in something while disregarding the facts, may I suggest religion? In science you only cause amusement. Oh no, thank you for the compliment, since science is the a search for the truth, what makes you happy? So in your opinion there is no flaw in the Giza Pyramid's construction, so then why did that flaw occur? [media=] [/media][wfit/] Edited May 4, 2014 by 029b10 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #105 Share Posted May 4, 2014 In my reality very soft sand is much harder to walk on, etc.(it's harder to lift your FOOT out, and you lose TRACTION) That is interesting. You might call up Nike and see if they make a shoe that won't slip in loose sand. 1 Link to comment Share on other sites More sharing options...
seeder Posted May 4, 2014 #106 Share Posted May 4, 2014 (edited) That is interesting. You might call up Nike and see if they make a shoe that won't slip in loose sand. CK you cannot keep assuming they trudged thru all this sand! They were clearly not too stupid to be able to build huge structures, yet not figure out how to do so - without getting bogged down!! . Edited May 4, 2014 by seeder 2 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #107 Share Posted May 4, 2014 In some ways this argument would be largely definitions and perspectives but in most real ways a car gets stuck in the sand because the friction is too high for the engine and tires to pull itself out. What the hell are you talking about? This couldn't be more wrong. Once a wheel is sunk below its axle no amount of power can remove it. A wheel can't even turn if the impeding force is at the height of the axle. More power might spin the wheel but will not result in a forward force. This is called loss of traction. Remember too that in order to move the vehicle actually has to move upward from the hole it's dug which further impedes the ability to move forward. A great deal of energy is required to lift the vehicle. Thanks, but I think I did remember this when I said most recovery methods involve digging and removing sand. When something gets bogged down in sand it's more appropriate to think of the friction as approaching infinity or at least an amount greater than its ability to apply forward force. This is why I keep talking about the forces applied to the sled with a stone on it. As long as the stone stays on top of the sand it has "low" friction but any wiggling or unevenness of the pull will result in it falling in and then it's just not going to move. No... to be stuck in sand, the surface has moved - not the vehicle. This represents a loss of traction. To transmit torque to the ground there has to be enough traction.The point of all this is to demonstrate that sand, or any loose surface, is a low friction surface. 2 Link to comment Share on other sites More sharing options...
scorpiosonic Posted May 4, 2014 #108 Share Posted May 4, 2014 (edited) Quoting ck, 'When something gets bogged down in sand it's more appropriate to think of the friction as approaching infinity or at least an amount greater than its ability to apply forward force. This is why I keep talking about the forces applied to the sled with a stone on it. As long as the stone stays on top of the sand it has "low" friction but any wiggling or unevenness of the pull will result in it falling in and then it's just not going to move.' Mangoze re, "No... to be stuck in sand, the surface has moved - not the vehicle. This represents a loss of traction. To transmit torque to the ground there has to be enough traction." Well said, and every drag racer's goal....without traction, it's just a waste of horsepower, (applied force). The sledge stays on top of the sand, and is supported by the sand. Like a camel's foot, it sinks in a bit w/ each step, but just to a point, then is supported. IF the sand didn't support the sledge, etc...then it was probably quicksand and would've been avoided. (It's obvious to some of us that the AE would've planned their routes carefully considering the work involved..) Edited May 4, 2014 by scorpiosonic 2 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #109 Share Posted May 4, 2014 I don't believe that what's a Giza is really sand at all. It's not "sand" now and it wasn't when the pyramids were built. It's extremely "dirty" sand mixed with all sorts of particulate matter in a wide range of sizes. "Sand" is a specific type of stone segregated into a narrow spectrum of sizes by wind or water (usually). Very small material and dusts will change the nature of the "sand" when it gets wet. It will tend to make it turn into mud rather than a hard surface like wet sand. "Mud" can be as much as about 60% sand in my experience. Now who's playing semantics?The point of the article in the OP is that the right amount of water will make a loose surface firm. You can encounter this where estuaries meet the ocean or surf. Here you will encounter loose dry sand, firm wet sand and loose wet sand. The loose wet sand is on the extremities of sand-bar that extends into the water way - where there is too much water in the mix. Loose dry soil can be just as difficult to walk on as dry sand. Again you need the right amount of water to make the surface firm. 2 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #110 Share Posted May 4, 2014 The point of all this is to demonstrate that sand, or any loose surface, is a low friction surface. All of reality is perspective. You brush a grain of sand from the top of a dune and say "see how little friction there is holding the sand". But if a microbe wanted to knock off the very top grain it would see that it is deeply embedded among many other grains. It will need tools or help to dislodge it and knock it off. You take your dune buggy out and drive right over the top of the sand and never notice the mileage decreases because it has such high friction. When you sink in you don't percieve it as high friction because the wheels spin and you know that on black top you'd be going 60 MPH. You think of it as the same as sinking into snow and not being able to move. What's actually happening on snow is the wheels are slipping until they dig a rut and you pass the point of no return. But on sand they aren't slipping on the snow as is clearly evidenced by the fact they are throwing sand. Even slick tires will throw sand be- cause it's the surface that is being pulled off. Ice or snow act as a unit and are slippery but sand disintegrates as a cohesive unit so no power is being transformed into a forward force. It's too much friction that causes the vehicle to sink and prevents it being able to climb out. The sand flies the vehicle stays put. Just like wet sand though, so long as you stay on top, so long as the tires rest on sand that remains as a cohesive unit then there's no problem. The torque is transferred to the ground and the vehicle moves ahead because the force is pushing backward through the tires. When this "cohesiveness" is no longer capable of supporting all the forces including weight, acceler- ation, and changes of acceleration (such as turning) then the tires sink in and friction increases even more than it was. Staying in a straight line at the same velocity increases the chances that the sand won't collapse beneath you. When you see soft spots don't change your speed or turn and we won't need this conversation. If you do sink in it has nothing to do with "low" friction and everything to do with "high" friction. 1 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #111 Share Posted May 4, 2014 CK you cannot keep assuming they trudged thru all this sand! They were clearly not too stupid to be able to build huge structures, yet not figure out how to do so - without getting bogged down!! I don't believe they ever dragged a stone at all. My point here is that "wet sand" is no more an answer to how the pyramids were built than "aliens did it". My point is that wet sand is not slippery and even if they dragged stones they didn't do it on wet sand. I'm not saying it's impossible to drag stones over wet sand merely that this nonsense is no more "scientific" than the belief the stones grew wings. 1 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #112 Share Posted May 4, 2014 Now who's playing semantics? The point of the article in the OP is that the right amount of water will make a loose surface firm. You can encounter this where estuaries meet the ocean or surf. Here you will encounter loose dry sand, firm wet sand and loose wet sand. The loose wet sand is on the extremities of sand-bar that extends into the water way - where there is too much water in the mix. Loose dry soil can be just as difficult to walk on as dry sand. Again you need the right amount of water to make the surface firm. The behavior of wet particulate matter is not "semantics". Sinking in or not sinking in is not "semantics". Look at the "sand" in that first post. I don't doubt wetting that sand will make it hard. I doubt that sand is in any way relevant to what they had at Giza. No amount of water will make small particute matter hard. It merely turns it to mud. 1 Link to comment Share on other sites More sharing options...
Mr.United_Nations Posted May 4, 2014 #113 Share Posted May 4, 2014 Well they did in the movie 10,000 B.C. If that's what you're talking about? But from what has been shown, mostly man power and oxen . Here's a nice website that tells you about it all: http://www.cheops-py...dge-tracks.html Although I personally don't believe they bothered trying to pull those stones up steep ramps when they got to the pyramidal structure, but rather they used cranes instead (like the romans) to haul those stones up the pyramid the rest of the way. yeah must of got that, the only way they could do it was be some sort of early crane or lift Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #114 Share Posted May 4, 2014 Well said, and every drag racer's goal....without traction, it's just a waste of horsepower, (applied force). Once the wheels spin "horsepower" is irrelevant. The engine merely speeds up and it is not producing much power. People misunderstand and misapprehend the "laws" of nature. More than half of aeronautical engineers answer the question about the ability of a plane to take off from a conveyor belt incorrectly. Most statements made by most individuals about nature are factually and/ or technically incorrect. This applies to most scientists as well. We just don't notice and then we go get stuck in the sand. 1 Link to comment Share on other sites More sharing options...
scorpiosonic Posted May 4, 2014 #115 Share Posted May 4, 2014 (edited) Quoting ck, 'When something gets bogged down in sand it's more appropriate to think of the friction as approaching infinity or at least an amount greater than its ability to apply forward force. This is why I keep talking about the forces applied to the sled with a stone on it. As long as the stone stays on top of the sand it has "low" friction but any wiggling or unevenness of the pull will result in it falling in and then it's just not going to move.' Mangoze re, "No... to be stuck in sand, the surface has moved - not the vehicle. This represents a loss of traction. To transmit torque to the ground there has to be enough traction." Well said, and every drag racer's goal....without traction, it's just a waste of horsepower, (applied force). The sledge stays on top of the sand, and is supported by the sand. Like a camel's foot, it sinks in a bit w/ each step, but just to a point, then is supported. IF the sand didn't support the sledge, etc...then it was probably quicksand and would've been avoided. (It's obvious to some of us that the AE would've planned their routes carefully considering the work involved..) Like Mangoze has been trying to tell you ck, a loss of traction. ( And applies to humans walking in soft sand.) ck, "The engine merely speeds up and it is not producing much power..." As engine RPMs increase, the power output increases...but this power is wasted due to the loss of traction. Edited May 4, 2014 by scorpiosonic 1 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #116 Share Posted May 4, 2014 Like Mangoze has been trying to tell you ck, a loss of traction. ( And applies to humans walking in soft sand.) ck, "The engine merely speeds up and it is not producing much power..." As engine RPMs increase, the power output increases...but this power is wasted due to the loss of traction. "Power" is defined as the ability to do work. Spinning the tires requires very little work so very little HP is being generated. Much of the little bit of power being generated goes to increasing engine RPM which is only limited by its nature. Many engines will be destroyed by such high engine speeds though modern engines are more resistant to this. If all that power were actually being used then why is the car not accelerating much? Your understanding of this is incorrect just as your understanding of "traction" in sand is incorrect. Perhaps stated more accurately your perspective of these things occurs from a vantage that would not be consistent with an easy way to understand nature. Of course such perspectives return incorrect answers which are just wrong. The diff- iculty of walking in sand isn't caused by low friction or poor traction. One could legit- imately say that poor traction results from stepping on sand because it collapses but then one has a more complicated way of viewing the reality and just might call Nike to get a shoe with more traction on sand when the more appropriate solution is to get a snowshoe or something to spread your weight over a larger area. Mebbe Nike makes snowshoes. 1 Link to comment Share on other sites More sharing options...
questionmark Posted May 4, 2014 #117 Share Posted May 4, 2014 "Power" is defined as the ability to do work. Spinning the tires requires very little work so very little HP is being generated. Much of the little bit of power being generated goes to increasing engine RPM which is only limited by its nature. Many engines will be destroyed by such high engine speeds though modern engines are more resistant to this. If all that power were actually being used then why is the car not accelerating much? Your understanding of this is incorrect just as your understanding of "traction" in sand is incorrect. Perhaps stated more accurately your perspective of these things occurs from a vantage that would not be consistent with an easy way to understand nature. Of course such perspectives return incorrect answers which are just wrong. The diff- iculty of walking in sand isn't caused by low friction or poor traction. One could legit- imately say that poor traction results from stepping on sand because it collapses but then one has a more complicated way of viewing the reality and just might call Nike to get a shoe with more traction on sand when the more appropriate solution is to get a snowshoe or something to spread your weight over a larger area. Mebbe Nike makes snowshoes. No grasp of the reality yet? No movement is generated because there is more power on the tire than can be modified to movement and therefore is wasted as heat (also called burn-out among the professionals)... which is the reason you see all that smoke when tires spin. If you do not have enough power to make tires spin your chances of converting it into movement is much greater (but that is something that will be never learned by those driving an automatic). 1 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #118 Share Posted May 4, 2014 Mebbe Nike makes snowshoes. ...And if you get a snowshoe for walking in sand it won't matter if it's slippery or not because sand is extremely high friction. 1 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #119 Share Posted May 4, 2014 All of reality is perspective. You brush a grain of sand from the top of a dune and say "see how little friction there is holding the sand". But if a microbe wanted to knock off the very top grain it would see that it is deeply embedded among many other grains. It will need tools or help to dislodge it and knock it off. You take your dune buggy out and drive right over the top of the sand and never notice the mileage decreases because it has such high friction. When you sink in you don't percieve it as high friction because the wheels spin and you know that on black top you'd be going 60 MPH. You think of it as the same as sinking into snow and not being able to move. What's actually happening on snow is the wheels are slipping until they dig a rut and you pass the point of no return. But on sand they aren't slipping on the snow as is clearly evidenced by the fact they are throwing sand. Even slick tires will throw sand be- cause it's the surface that is being pulled off. Ice or snow act as a unit and are slippery but sand disintegrates as a cohesive unit so no power is being transformed into a forward force. It's too much friction that causes the vehicle to sink and prevents it being able to climb out. The sand flies the vehicle stays put. Just like wet sand though, so long as you stay on top, so long as the tires rest on sand that remains as a cohesive unit then there's no problem. The torque is transferred to the ground and the vehicle moves ahead because the force is pushing backward through the tires. When this "cohesiveness" is no longer capable of supporting all the forces including weight, acceler- ation, and changes of acceleration (such as turning) then the tires sink in and friction increases even more than it was. Staying in a straight line at the same velocity increases the chances that the sand won't collapse beneath you. When you see soft spots don't change your speed or turn and we won't need this conversation. If you do sink in it has nothing to do with "low" friction and everything to do with "high" friction. When driving your 4WD on the sand, you don't need to be concerned with the perspective of the microbe. It's what's known as an effective theory.When wheels spin on the sand we perceive a loss of traction because wheels spin. There is a waste of power and mileage increases. This is as simple as it needs to be for this purpose. That a single grain in contact with the tire may (as you keep wishing to point out) have a high friction coefficient cause the sand to be displaced. This because the sand as a granular material has a low internal friction. When you sink in you start to plow. Most vehicles are designed to plow, they are designed to move through air. It's harder to move sand than air. This is what the OP is about mitigating the plowing effect. Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #120 Share Posted May 4, 2014 No grasp of the reality yet? No movement is generated because there is more power on the tire than can be modified to movement and therefore is wasted as heat (also called burn-out among the professionals)... which is the reason you see all that smoke when tires spin. If you do not have enough power to make tires spin your chances of converting it into movement is much greater (but that is something that will be never learned by those driving an automatic). If that's HP then how come a little VW Bug can out-accelerate a dragracer doing a burnout? You're just mistaken. It requires a lot of power to lose traction with those big tires but once they begin to spin power requirements decrease. If you could actually apply the output undreds of horses to the tires they would not only burn out but they would burn up along with the wheels and anything else trying to restrain so much power. The VW bug will do a burnout on a frozen lake even longer than the dragracer can do it on asphalt. 1 Link to comment Share on other sites More sharing options...
scorpiosonic Posted May 4, 2014 #121 Share Posted May 4, 2014 "Power" is defined as the ability to do work. Spinning the tires requires very little work so very little HP is being generated. Much of the little bit of power being generated goes to increasing engine RPM which is only limited by its nature. Many engines will be destroyed by such high engine speeds though modern engines are more resistant to this. If all that power were actually being used then why is the car not accelerating much? Your understanding of this is incorrect just as your understanding of "traction" in sand is incorrect. Perhaps stated more accurately your perspective of these things occurs from a vantage that would not be consistent with an easy way to understand nature. Of course such perspectives return incorrect answers which are just wrong. The diff- iculty of walking in sand isn't caused by low friction or poor traction. One could legit- imately say that poor traction results from stepping on sand because it collapses but then one has a more complicated way of viewing the reality and just might call Nike to get a shoe with more traction on sand when the more appropriate solution is to get a snowshoe or something to spread your weight over a larger area. Mebbe Nike makes snowshoes. Like I said earlier, "As engine RPMs increase, the power output increases...but this power is wasted due to the loss of traction." The horsepower IS BEING GENERATED....but the car ISNT accelerating because the tires are spinning, (LOSS OF TRACTION). You continue to fail to perceive/accept the facts here, and you obviously are incapable of comprehending Physics, Engineering, simple science, Egyptology, traction, understanding the English language, etc. 2 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #122 Share Posted May 4, 2014 The behavior of wet particulate matter is not "semantics". Sinking in or not sinking in is not "semantics". Look at the "sand" in that first post. I don't doubt wetting that sand will make it hard. I doubt that sand is in any way relevant to what they had at Giza. No amount of water will make small particute matter hard. It merely turns it to mud. I guess that's why they have published this article; so you, as a scientist, can confirm your doubts by repeating their experiment. You can even use sand relevant to Giza.Water can increase the internal friction of granular material. The right amount of water will make it firm. We all look forward to the results of your experiment. 2 Link to comment Share on other sites More sharing options...
cladking Posted May 4, 2014 #123 Share Posted May 4, 2014 This is what the OP is about mitigating the plowing effect. Yes. The study makes the rather obvious point that it's easier to move on top of sand than through sand. They have done nothing at all to show that their demon- stration is relevant to conditions at Giza. They have not "shown" their work to even prove that their extrapolations are accurate to a full scale sled. They used a "sled" with no skis and a very steady pull from very low to the ground. Thisa isn't to say the study is entirely groundless, merely that it can't be evaluated with the facts presented. Even if it could be evaluated and were found sound, there is absolutely no way to know if it has any bearing on how stones were moved. It is just more "junk science" like almost all modern science in the popular press. It is not designed to make new ground but to sway public opinion because people have the idea that any pronouncements from "science" is somehow sacred. One day milk is the best food sinvce sliced bread and the next its artery clogging fat that will put you in an early grave. One day the milk industry spends its money to "lobby" Con- gress and the next day they buy a lab somewhere to find a new health benefit of milk. Wet sand is hard. Maybe this is something some people hadn't thought of. It's a great topic but it's not a revelation on order with the unified field theory or the higgs-boson. There's simply no evidence it has anything to do with moving pyramid stones and the logic weighs against it being relevant due to the many reasons listed. 1 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #124 Share Posted May 4, 2014 ... Most statements made by most individuals about nature are factually and/ or technically incorrect. This applies to most scientists as well. ... Rubbish! This is not true at all! No aeronautical engineer would say this. Not even a pilot, or anyone who saw the relevant Mythbusters episode would say this. You are perhaps talking about the general public, but certainly not experts. 1 Link to comment Share on other sites More sharing options...
Golden Duck Posted May 4, 2014 #125 Share Posted May 4, 2014 ... Most statements made by most individuals about nature are factually and/ or technically incorrect. This applies to most scientists as well. We just don't notice and then we go get stuck in the sand. Yourself included, right? Link to comment Share on other sites More sharing options...
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