چكيده به لاتين
One of the leading challenges in the high-pressure injection method is the waste of a large amount of cement (spoil) that comes to the ground during high-pressure execution. Therefore, identifying its characteristics seems important. In this research, which is one of the first researches in this field, the knowledge of the physical and resistance characteristics of spoil has been desired. Therefore, samples were collected from different points of projects across the country and uniaxial resistance, volume wave velocity, density and water absorption percentage were investigated. According to the obtained results and comparing them with each other, it can be concluded that the type of soil in which jetgrouting is performed has a significant effect on the compressive strength of the resulting spoil, which led to the classification of the results based on the type of soil.
In this research, the spoil resulting from jetgrouting operation in 5 types of sand, clay, clayey sand, silty sand and fill material was investigated.
By testing the compressive strength of spoil in different soils, it can be concluded that the spoil of sandy soil has a maximum average compressive strength of 18MPa and silty sand soil has a minimum average compressive strength of 7.1.
By calculating the modulus of elasticity and the Beta coefficient (the ratio of the modulus of elasticity to the compressive strength), the values of the Beta coefficient for the spoil of sand soil are between 100 and 270, clay soil is 70 to 130, clayey sand soil is about 165 to 270, silty sand soil is 14 to 90 and Manual is variable 90-250.
Regarding the density of spoil in different soils, Clayey sand soil has the highest average density of 1844.5 kg/m3 and Clay soil has the lowest average density of 1704.8 kg/m3, and silty sand soil with an average water absorption percentage of 39.2 has the highest amount of water absorption and clayey sand soil with the amount of 17.2 has the minimum water absorption.
On the other hand, by measuring the volumetric wave velocity of spoil of different soils, it was observed that sandy soil with a value of 3232.9 meters per second and Maual soil with an average value of 1955.2 had the maximum and minimum volumetric wave velocity.
Considering the type of soil and examining the characteristics of density, percentage of water absorption and volumetric wave speed with compressive strength, it can be concluded that the compressive strength of spoil with different soils increased with increasing density and volume wave velocity increases with decreasing water absorption.
Also, another important result is that the limits of the compressive strength of spoil are within the range of variation in the compressive strength of soil cements resulting from soil improvement processes.
Therefore, it is important to prevent the waste of these materials and check the possibility of reusing them.
