Penetratsiooni katsed teedeehituses

Lõputöö autori eesmärgiks oli uurida kahte dünaamilise penetromeetri DCP (Dynamic Cone Penetrometer) ja PM-1. Selleks teostas lõputöö autor mõlema penetromeetriga katsed Tallinna Tehnikakõrgkooli parklas. Käesolevas lõputöös uuriti mõlema penetromeetri otstarvet, kuidas ning milliste valemite abil leitakse materjali mehaanilist tugevust, pinnase geotehnilisi omadusi ning materjali elastsust. Kuidas käib mõõtmine nii DCP kui ka PM-1 penetromeetriga. DCP penetromeetriga saadud keskmine elastsusmoodul näitas, et parkla muldkehast pinnas on väga nõrk. Samas PM-1 penetromeetriga saadud tulemus näitas, et parkla pinnase tihendustegur on maksimaalne. Autori ettepanekuks on kontrollida sama parkla INSPECTOR tüüpi seadmega, et kontrollida DCP penetromeetriga saadud tulemust ning kas vastab tõele, et parkla muldkeha on nõrk. Mõõtetööde käigus selgus, et lõputöö autori jaoks on mugavam teha katseid DCP penetromeetriga, mida kasutatakse enamasti Ameerikas ning just sellepärast, et sellele langeb suurem raskus koonust süvistavale osale ning lõpptulemuseni jõutakse kiiremini. Puuduseks DCP penetromeetril on lõputöö autori arvates selle mõõtmiseks valmis seadmine. PM-1 penetromeetri puuduseks toob autor välja koonusele langeva raskuse kaalu, mis on 2,5 kg ning tänu sellele tuleb ühel katsel väga palju kordi raskust langetada. Eeliseks viimasena mainitud penetromeetril on see, et penetromeeter on ühes tükis ning mõõtmiseks valmis seadmisel aega ei kulutata. Autori arvates on mõlema penetromeetriga on võimalik leida pinnase tugevust, kuid antud töös sobis selleks DCP penetromeeter, sest PM-1 penetromeeter on mõeldud liivaste pinnaste uurimiseks. Küll aga ei ole võimalik mõlemaid tulemusi omavahel võrrelda, kuna DCP-ga saadud tulemused on megapaskalites, aga PM-1 penetromeetriga mõõtes leiame tihendusteguri.

Penetration Tests at Road Construction The purpose of this thesis was to study two different penetrometers, DCP (Dynamic Cone Penetrometer) and PM-1. For this, author conducted experiments with both penetrometers in TTK University of Applied Science parking lot. Both penetrometers purpose was studied, how and with which formulas do they find material mechanical strength, soils geotechnical features and material elasticity. How to measure with both DCP and PM-1 penetrometer. The average modulus of elasticity obtained with the DCP penetrometer showed that the soil from the embankment of the car park is very weak. However, the result obtained with the PM-1 penetrometer showed that the compaction factor of the parking lot soil is maximal. The author proposes to check the same parking lot with an INSPECTOR device to check the result obtained with a DCP penetrometer and whether it is true that the car park embankment is weak. During the measurements, it became clear that it is more convenient for the author of the dissertation to perform experiments with the DCP penetrometer, which is mostly used in America, and precisely because it places a heavier weight on the conical part and achieves the final result faster. The disadvantage of a DCP penetrometer is, in the opinion of the author of the dissertation, the time it takes to set the penetrometer up. The disadvantage of the PM-1 penetrometer is the weight falling on the cone, which is 2.5 kg, and as a result, the weight has to be reduced many times in one attempt. The advantage of the latter penetrometer is that the penetrometer is in one piece and no time is spent setting it up.

According to the author, it is possible to find soil strength with both penetrometers, but in this work the DCP penetrometer is more suitable, because the PM-1 penetrometer is intended for studying sandy soils. However, it is not possible to compare the results, because the results obtained with DCP are in megapascals, but when measuring with a PM-1 penetrometer, we find the compaction factor.