Un método para la determinadón analítica de la distribución de probabilidad de los estimadores de la EHE

An analitycal method to determine the probability distribution of statistics used in EHE

The statistics used for estimating the characteristic strength of concrete in the new Spanish Structural Concrete Instruction (EHE) were firstly included in the 1973 version (EH-73). A new development of the current version EHE is to check the variation coefficient of such strength population by mean of a new statistic. All of these statistics are based on a numerical simulation on the standarized Gaussian distribution since their analytical distributions were considered very difficult to obtain anyway. In this work a procedure is exposed which simplifies very much the calculation of such probability distributions. Obtaining the probability distributions of characteristic strength estimations for four, six and eight test data are detailed. The probability distributions for 2nd, 3nd and 4th order statistics (taken in increasing order) are also detailed to check, together with data from references, results obtained from our procedure; The work is interesting to design new statistics avoiding the need for numerical simulations every time. It is also interesting to discuss, improve, and design specific internal quality control schemes for ready mixed concrete plants. The statistics and their distributions can be obviously applied to any variable whose control is desired.