Pyramid builders probably used ramps to raise most of the building material. Mudbrick ramps have been found near the Middle Kingdom pyramids of el-Lisht, including ramps that must have been used to raise stone up onto the pyramid of Senusret I. Construction ramps for the 4th Dynasty stone-block pyramids must have been large enough that we should expect to find sizable deposits of the material from which they were composed. At Giza, the quarries south of the pyramids are filled with millions of cubic meters of tafla, gypsum, and limestone chips. Remains of ancient ramps and construction embankments associated with structures other than pyramids at Giza are composed of such material.
Ideas about the form of pyramid construction ramps can be reduced to two major proposals: (1) a sloping straight ramp that ascends one face of the pyramid, and (2) one or more ramps that begin near the base and wrap around the pyramid as it rises during construction. Straight ramps have been found at the unfinished step pyramids at Sinki (South Abydos) and Saqqara (that of Sekhemkhet). Serious problems result in using a straight ramp for the higher reaches of the large 4th Dynasty pyramids. In order to maintain a low functional slope (e.g. about 1 unit of rise in 10 units of length), the straight-on ramp must be lengthened each time its height against the pyramid is increased. Either work stops during these enlargements, or the ramp is built in halves and one side serves for builder traffic while the ramp crew raises and lengthens the other half. In order to maintain a functional slope up to the highest part of the pyramid, the ramp would need to be extremely long. At Giza, this slope would take the ramp for the Khufu pyramid far to the south beyond the quarry where Khufu’s builders took most of the stone for the core of his pyramid.
The wrap-around ramp has been proposed in two major forms, either supported on the slope of the pyramid or supported on the ground and leaning against the faces of the pyramid like a giant envelope with a rising roadbed on top. Since it cloaks most of the pyramid, such a ramp makes it difficult to control the squareness and slope as the pyramid rises by checking back to the part already built. A ramp founded on the 52-53° sloping faces requires extra stock of stone on the casing blocks in wide enough steps to support it, a requirement that is not met by the unfinished granite casing on the lower part of the Menkaure pyramid. Near the top, the faces of the pyramid become too narrow to support any large ramp which would anyway become increasingly steep.
The form of the supply ramps probably changed as the pyramid rose. Near the base, the builders could have delivered stone over many short ramps. As the largest pyramids rose about 30m above ground, it is plausible that a principal ramp ran to one corner and along one side, leaning against the pyramid and gaining rise with the run. To complete the top of the pyramid, very small ramps, or levers, could have been used on steps left on the pyramid faces. Once the top was complete, the masons could have trimmed away the steps.
It has been speculated that many or most of the stones were raised by using levers to “seesaw” a block upward, raising one side at a time and placing supports underneath, then raising and supporting the opposite side, for which stepped supporting platforms would have been needed. Except for the uppermost blocks, which become smaller, it is inconceivable that such lever-lifting was used on the stepped courses of the core stone or the undressed casing stone to lift most of the blocks. Lever-lifting requires the use of well-planed wood cribbage, or stacked supports, as the blocks are raised, vastly increasing the wood requirement.
Evidence of ancient levering indicates it was mostly used for side movements and final adjustments. It is possible that levering was the only means to raise the last few blocks of the highest courses, near the apex, once the builders had brought them as far as they could on ramps.
The wrap-around ramp has been proposed in two major forms, either supported on the slope of the pyramid or supported on the ground and leaning against the faces of the pyramid like a giant envelope with a rising roadbed on top. Since it cloaks most of the pyramid, such a ramp makes it difficult to control the squareness and slope as the pyramid rises by checking back to the part already built. A ramp founded on the 52-53° sloping faces requires extra stock of stone on the casing blocks in wide enough steps to support it, a requirement that is not met by the unfinished granite casing on the lower part of the Menkaure pyramid. Near the top, the faces of the pyramid become too narrow to support any large ramp which would anyway become increasingly steep.
The form of the supply ramps probably changed as the pyramid rose. Near the base, the builders could have delivered stone over many short ramps. As the largest pyramids rose about 30m above ground, it is plausible that a principal ramp ran to one corner and along one side, leaning against the pyramid and gaining rise with the run. To complete the top of the pyramid, very small ramps, or levers, could have been used on steps left on the pyramid faces. Once the top was complete, the masons could have trimmed away the steps.
It has been speculated that many or most of the stones were raised by using levers to “seesaw” a block upward, raising one side at a time and placing supports underneath, then raising and supporting the opposite side, for which stepped supporting platforms would have been needed. Except for the uppermost blocks, which become smaller, it is inconceivable that such lever-lifting was used on the stepped courses of the core stone or the undressed casing stone to lift most of the blocks. Lever-lifting requires the use of well-planed wood cribbage, or stacked supports, as the blocks are raised, vastly increasing the wood requirement.
Evidence of ancient levering indicates it was mostly used for side movements and final adjustments. It is possible that levering was the only means to raise the last few blocks of the highest courses, near the apex, once the builders had brought them as far as they could on ramps.
