الفهرس 
Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
This investigation aimed to make a comprehensive comparison between the concrete prism tests C 1293 and C 1105 for 360 days and the accelerated mortar bar test (C 1260) at the age of 28 days. Ten samples of aggregate were collected from the El-Alameen area and the Ataqaa area. Part of them were limestone and the other parts were dolostone. Concrete cubes (10 x 10 x 10)3 cm were also cast and immersed in sodium hydroxide solution at 1N and 2N NaOH to perform physico-mechanical tests for 360 days of curing. The hydration products produced in hardened specimens were investigated using various techniques.
Several conclusions were reported based on the observations achieved:
1-Sample E4 gave the least linear expansion of the accelerated mortar bar test (C 1260) at the age of 28 days of curing than the other samples, which were extracted from the El Alameen area.
2-Sample E4 showed the least linear expansion of the concrete prism test, whether it was an alkali carbonate reaction (C 1105) or an alkali silica reaction (C 1293) at the age of 360 days of curing.
3-Sample (E4) also had the highest improvement in physico-mechanical properties than the other samples which were extracted from the El Alameen area.
4-Sample (E3) showed an increase in the linear expansion of the alkali accelerated mortar bar test (C 1260) and also showed the highest expansion in the concrete prism, which therefore caused a reduction in the concrete’s compressive strength due to the high content of silica gel.
5-Sample A1 outperformed the other samples from the Ataqqa area in all tests, whether mortar bar (C 1260) or concrete prism (C 1293 and C 1105), achieving high compressive strength and low porosity.
6-Sample A3 showed an increase in the linear expansion of the alkali accelerated mortar bar test (C1260), due to the high quantity of silica gel. Also, A3 indicated the highest expanding in the concrete prism (C 1293 and C 1105), resulting in a decrease in the compressive strength of concrete.
7- All E and A samples showed the low resistivity in 1N and 2N NaOH up to 360 days of immersion.
8-All E and A samples immersed in 2N of NaOH led to a weakening of physico-mechanical properties than immersed in 1N of NaOH because the higher concentration of sodium hydroxide gave worse conditions for invisible foundations or places where agricultural or industrial drainage was located.
9-The XRD analysis proved that the most of C3S, very little hydration was produced, proving that the sample was more reactive and disintegrated into a high alkaline porosity solution.
10-The results of SEM examination proved that the interfacial transition zone (ITZ) of E4 and A1 was stronger than the other samples.
11-Concretes composed of limestone (E) aggregates seemed to have a greater influence on enhancing mechanical properties than concrete formed of dolostone (A) aggregates.
12-CPT (C 1293) was thought to be more representative of problems in reality because of the duration of the test period, so the accelerated alkali reaction AMBT (C 1260) achieved better results than the concrete prism test CPT (C 1293).
13- ACR (C 1105) was recognized to be more representative of specific problems, so the accelerated mortar bar test AMBT (C 1260) was parallel to the alkali carbonate reaction ACR (C 1105) and better in terms of time.
14- The accelerated mortar bar test AMBT (C1260) proved that it achieved the goal of the alkali carbonate reaction ACR (C1105) and the alkali silica reaction of concrete CPT (C 1293). it was mentioned earlier that the ages of 16 and 28 days in AMBT (C1260), represented the ages of 270 and 360 days in the concrete prism (C 1293, C 1105).
15- At samples E5, E6 and E7 the expansion reached 0.08% at 16 days and with increasing of the age to 28 days the expansion increased to 0.1%.
16- The sample that exceeded the permissible limits tested by specification AMBT (C1260), which therefore led to a saving of work time in the sites or evaluation of a quarry with evidence that gave a clear result according to the limits of the specification.
17- Many benefits of the accelerated mortar bar test AMBT (C1260) were achieved in terms of reaction speed affected by the high temperature. a) The sample was considered harmless when the alkaline expansion was not more than 0.1% at 16 days. b) The alkaline expansion was greater than or equal to 0.1%, the sample must be measured at 28 days until a judgment was made on the suitability of the sample, as it was used in other fields, taking the necessary precautions. c) The sample was considered harmful, if the expansion was greater than 0.2% at 16 days of age. This reaction was strong due to exposure to 1N NaOH, so efficiency was achieved for laboratory experiments and for the market in terms of sites and quarries.
18- In light of these previous results, it is deduced that AMBT (C 1260) fits and matches (CPT) C1293 and (ACR) C 1105, as it is used in the Egyptian Code for Laboratory Tests Manual because of its validity in all circumstances, it is used instead of (CPT) C1293 and (ACR) C1105.