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I take it since you ask the question, that there are no traces remaining of any sort of construction that might be considered to be a ramp. Am I right?
Actually you are wrong as there are two different features at Giza that have been identified as ramps. Neither is anything like the remains of a single straight on ramp though.
But there is strong evidence for small ramps having been used for exit from the quarry and actual ramps still survive elsewhere in Egypt although most are later than the Old Kingdom.