Aggregate Impact of the Country in Concrete Durability , that Works in Normal Environmental Conditions

Production and use of durable concrete in reinforced concrete structures is a necessity in our country. In this article it was treated as affecting the characteristics of aggregates in durable concrete production, when they work in normal environmental conditions . To achieve this goal have produced concrete of class C35 / 45 with aggregate taken in careers mountain and river. The other components are the same in mix design concrete. Water-cement ratio is 0.5 and 0:35 realized. Comparisons are made of the resistance to compression and water penetration. Cubes of concrete had been produced and treated in terms shipyard. There have been comparisons of results and following. Today in Durres, even wider, buildings constructed with durable concrete are very few in now days. Geological studies show that the soil in foundation has low retaining capacity for this city due to high friction angle. This is also one of the other factors that Seismicity of the area is very high, up to level 9 ball of Rihter. The purpose of this article is the production of durable concrete with low permeability of water. The project is constructed in our country and in particular in Durres where groundwater level is higher and the use of space efficiently needs to build parking with underground floor.


INTRODUCTION
With the use of concrete durability we go further and ask that concrete have much longer life not only to the destruction but their work time or as called "lifetime" or the time before the repair, be much longer.This requires that we seek concrete durability and longevity of the structure reinforced concrete.For this purpose we must consider: 1.To obtain concrete durability in use should distinguish between possible life of concrete as a material to be used in specific environmental conditions and longevity of concrete factual deed therefore be taken into account that concrete properties in the composition of the structure.
2. The water impermeable concrete with a resistance to water penetration under ISO 7031-1994 standard specifications, or otherwise rely on standard EN 206-1 , permeability should be up to 20 to 50 mm.

Aggregates
Coarse and fine aggregates obtained from Mat river Perroi i Thate and Fushe Kruja quarry units have been used for this study.Maximum size of coarse aggregate used is 25 mm and specific gravity of ranging from 2.6 -2.7 kg/m3 based on standard S SH 509:1987; bulk density 1484 kg/m3 and fine modulus 6.07.For fine aggregates maximum size used is 5 mm and specific gravity of ranging from 2.687 kg/m3 based on standard S SH 509:1987; and fine modulus 2.74.Mount aggregates have been derived from carbonate rocks, with high content of limestone.
River aggregates are with originate volcanic and therefore have a high content of basalt.

Water
Potable tap water available production site was used for mixing and curing of concrete.The water is filtrate based on standard S Sh 2751:1987.

Concrete admixtures
Additives used in this project are; Chryso-Fluid Premia 180(superplasticizer) and in quantities 3 l/m3 concrete.Additives were used to produce concrete class C 35/45 MPa and the result was decreasing the amount of water.The effect of using the lowest amount of water is increasing the durability and resistance of concrete.

Durable concrete mix design
Mix design is a process of selecting suitable ingredients for concrete and determining their proportions which would produce, as economically as possible, a concrete that satisfies the Orion project requirements.All mix designs data for durable concrete used in our project are represented in Table 2 The compressive strength of concrete is considered as the index of its quality.Therefore the mix designs are generally carried out for a particular compressive strength of concrete with adequate workability so that the fresh concrete can be properly mixed, placed and compacted.
After 28 days period of curing, the specimens were taken out of the curing tank and there were tested besides measuring the fresh properties (workability, air content and concrete temperature); following tests such as permeability of concrete cubes and chlorides contents are measured.

Compressive strength of concrete cubes
Compressive strength, of mixes was determined at various ages as per EN 12390-3:1999 and EN 12390-5:1999 are given in table 3.1.Cube Compressive strength at the age 7 and 28 days.After casting the specimens were covered with sheets to minimize the moisture loss from them.Specimens were demoulded after 24-hours and then cured in water at approximately room temperature till testing.Compressive strength tests for cubes were carried out at 28 days.All the specimens were tested in an automated compressive strength machine shown in Figure 3.1: Albanian standards S EN 206-1: 2003, with resistance class C35 / 45, taken in Fushe Kruje by concrete and Shkodra Vega by Mat River to Dry Stream The details of the experimental program have been reported in this study.Concrete ingredients produced by the Albanian standard S SH EN 206-1:2003, with resistance class C35/45, were taken in Fushe Kruja from Vega concrete production site.The concrete is produced in SAG concrete plant.Composition of Portland cement, CEM I 42.5 R, from ANTEA, type cement conforming EN 197-1 was used in this study.

Figure 1 :
Figure 1: a) Coarse and b) fine aggregates PSD analysis river .

Figure 2 :
Figure 2: a) Coarse and b) fine aggregates PSD analysis river

Figure 4 :
Figure 4: a) Coarse and b) fine aggregates PSD analysis river

Figure 5 :
Figure 5: a) Coarse and b) fine aggregates PSD analysis river

Figure 8 :
Figure 8: a) Coarse and b) fine aggregates PSD analysis river

Table 2 .
1.3: Mechanical Properties of CEM I 42.5 R TITAN Cement

Table 2 .
1.3.1:Chemical analysis of water used in mix design

Table 2 .
.2.1.1.In present study durable concrete class C35/45 was produced with river raw material.All mix designs are formulated based on specifications of EN 206-1:2003 standard.Date 10.10.2013Table 2.2.1.1:Mix design of concrete from Kruja mountain 2.1.1:Mix design of concrete from Mat river