Researching of properties of expanded clay concrete on cement-ash binder.

Ukraine is a state with a powerful industrial base,the waste of which is ash. The use of ash as a binder for the production of expanded clay concrete solves the problem of its disposal. Studies of expanded clay concrete on carbonates and and cement-ash binder were carried out.The research results showed that it is possible to manufacture building structures from this material, including load-bearing ones. Experiments have confirmed the effectiveness of using a cement-ash binder [Vilkov, 1984]. The article provides recommendations on the technology of production of expanded clay concrete mixture and determination of optimal composition. Were made and tested samples of expanded clay concrete on a cement-ash binder with varying degrees of reinforcement with dimensions of 100x150x1200mm. The bearing capacity, crack resistance and deformability of expanded clay concrete were determined by testing on hydraulic press. The compressive strength of the studied expanded clay concrete was tested by loading samples with dimensions of 10x10x10cm and 10x10x40cm. The perspectives of using expanded clay concrete on a cement- ash binder are analyzed. Keywords: expanded clay concrete, industrial waste, binding material, ash, carbonate send, strength, deflection, deformation, building construction

Vegetable growing on expanded clay

As soilless gardening is becoming more popular, the broadening of knowledge on growing media with low environmental burden is continuously of interest. In the experiment we investigated the applicability of Liapor Hydro clay pebble products in greenhouse production of sweet pepper, tomato, eggplant and cucumber, using rockwool as the control medium (sweet pepper, tomato, eggplant) and peat-perlite mix (cucumber). The volume of substrate per plant was 5 liters in the case of pepper and tomato, 10 liters in the case of cucumber and 7.5 or 15 liters in the case of eggplant. Experimental results demonstrate the suitability of expanded clay as growing medium for the soilless greenhouse production of all four vegetables. In the case of eggplant, results relative to growing medium quantity, showing that the greater root volume produces greater yields, are an indication of the importance of making the choice of the volume in accordance with the growing medium

Autogenous shrinkage, speciality of high performance concretes

Autogenous shrinkage is a consequence of self dessication in pores of hardened cement paste and is, at high performance concrete significantly greater than that of the ordinary concretes, mainly due to low water to cement ratio. In the graduation thesis we examined the main mechanisms that cause autogenous shrinkage. It can be reduced by internal curinginternal water reservoirs. As internal water reservoirs we used pre-soaked expanded clay Liapor. On specimens, in which we replaced 12 % of aggregate with pre-soaked expanded clay, we measured shrinkage and compressive strength. The results were compared with previously performed tests on high performance concrete without additives and on high performance concrete with addition of pre-soaked lightweight aggregate Lehnjak. We concluded that content of pre-soaked expanded clay has positive effect on shrinkage, but negative effect on the compressive strength

Durability of Lightweight Expanded Clay Aggregate Concrete

AbstractThe paper describes a development and use of lightweight concrete and lightweight self-compacting concrete using artificial lightweight aggregate based on expanded clay for ready mix concrete and precast elements. The objective of this research was to evaluate the lightweight concrete on durability of concretes placed in chemically aggressive liquid and gaseous environments (high concentrations of sulphate, chloride ions, automotive gas, oil and gaseous CO2 and SO2 environments)

The Effects of Tragacanth Addition on the Thermal and Mechanical Properties of Lightweight Concretes Mixed with Expanded Clay

The effects of adding tragacanth, which is a natural resin, as expanded clay aggregate and binder to specimens on the thermal and mechanical properties of lightweight concretes has been examined in this study. Expanded clay with diameters of 4 - 8mm and by proportion 5%, 10% and 20% of cement’s weight was added to specimens in the study. As a binder, by addition of 1% tragacanth to cement at the rate of 1%, new lightweight concrete specimens with densities varying between 867 kg/m3to 1452 kg/m3were produced. Tragacanth with the same proportions of mixture was prepared in pure specimens in order to compare. Water / cement ratio was kept constant in all mixtures. At the end of a drying time of 28 days, thermal conductivity, specific heat capacity, compressive strength, modulus of elasticity, water absorption and drying quantities of specimens were confirmed. As a result, decrease of thermal conductivity, density and compressive strength of specimens was seen through adding tragacanth and raising the amount of expanded clay

Modified expanded clay lightweight concretes for thin-walled reinforced concrete floating structures

Reinforced concrete floating structures have much more durable metal structures and do not require frequent repairs. Heavy and lightweight shipbuilding concrete is used for these structures. Floating structures are operated in difficult climatic conditions. Properties of modified expanded clay concrete for thin-walled reinforced floating structures were investigated. The experiment was carried out according to the 3-factor optimal plan. Concretes with the strength of up to 43 Mpa, with water resistance up to W12 and the average density of up to 1750 kg/m3 were obtained. Due to the use of expanded clay lightweight concrete, the carrying capacity of a ship, in particular, the floating dock, is increasing, and the comfort of people and technological equipment is increasing. Regulations for the technology of manufacturing modified shipbuilding expanded clay lightweight concrete for the construction of thin-walled floating structures and floating docks were developed and approved. The results of the research were used in the development of the national standard of Ukraine "Shipbuilding Concrete"

GEOLAB - Transnational Access project LIWEMAT – Deformation characterisation of LIghtWEight foundation MATerials

Proper use of lightweight materials as construction material for various types of infrastructure brings a lot of advantages to European critical infrastructure related to weight reduction and prevention of progressive heating or freezing of its structural elements. Large-scale Triaxial Apparatus was used to perform the loading tests, which enables the characterization of materials at very small strain ranges with a very high accuracy level of load-displacement control. The apparatus has rigid confining aluminum frames with a height of 3 cm and cross-section of 40 x 40 cm, enabling prismatic specimens with a height of up to 80 cm to be tested. This research aims to determine the characteristics of expanded clay and foamed glass aggregates through laboratory testing, performing cyclic loading for the stiffness and damping evaluation, which would be beneficial parameters for numerical simulations. Testing material The foam glass aggregate has a homogeneous microstructure with approximate uniform shape and sizes. Foam glass aggregate is considered one of the best solid isolation materials with several unique properties. It can be widely used in many applications such as basement walls, foundations, floors and roofs, terrace and garden covers, rooftops, and parking areas. The expanded clay aggregate is round shape with different sizes with small, air-filled cavities, with dark brown, reddish, brown-red or gray colors, which depends on the chemical composition of the expanded clay. The lightweight expanded clay aggregate has bulk density from 250 kg/m3 to 710 kg/m3, mostly dependent on the size of the aggregate