The paper analyzes the traditional mechanic technique of concrete demolition and the promising hydro demolition techniques from viewpoint of waterworks operators. The mechanical concrete demolition technique using chisel hammers is immediately available for the use and relatively cheap, but it is associated with considerable labor cost, generation of dust and noise. Concrete hydro demolition technique using high-pressure water has much higher productivity and reduces repair completion time, does not damage reinforcement, and ensures good adhesion of new concrete to old concrete. Basic technical characteristics of hydro demolition equipment and its pricing are given. On the basis of the current situation with regard to the estimated regulation and financing of construction projects, including from budgetary funds, the author considered the possibility of using promising methods of removing exposed concrete of lock chamber walls. A comparison was made between the cost and the regulatory and actual labor intensity between the methods of mechanical and hydraulic destruction of concrete. It has been shown that application of the hydraulic demolition technique is constrained by financial capabilities and estimates regulatory requirements. For substantiation of using the concrete hydro demolition techniques, operators need to adjust the regulatory framework for federal assessments.

The construction organizations lack adaptive infrastructure. It is required to use more intensively SMART-technologies of design and construction. Purposes of this article: a) the system analysis of categories "competitiveness", "stability", "rating of the company" for the construction organizations; b) to construct and investigate economic and mathematical model of competitiveness of the construction organization; c) to determine parameters of self-organization of construction company; d) to construct an identification algorithm for model. These new tasks also answer the purposes of modern construction business, problems of forecasting of its development. Using methods of the system analysis and modeling, in work three levels of the analysis of construction business are considered: macrolevel (level of the state), mesolevel (level of the region) and microlevel (level of the company). For example, 10 various classes of competitiveness of construction companies are offered. It improves the classification used traditionally. The new economic and mathematical model on the basis of production functions of type of Cobb-Douglas is constructed. The algorithm of its identification on the basis of situational scenarios is also developed. The algorithm finds parameters which will allow to define competitiveness of construction company a priori. The offered research has a development, for example, is possible to use for the forecast of adaptation of the enterprise.

Concrete mixes are usually delivered to construction projects with the help of special vehicles. Depending on its fluidity, cement setting rate, temperature and relative humidity of carriage conditions, as well as a distance and road condition, transportation of a concrete mix may be done in concrete mixer trucks and ready-mix delivery trucks, also in buckets and hoppers mounted on vehicles (bucket trucks). At the same time, it is necessary to reduce the number of transship operations as much as possible and, wherever practicable, unload a mix directly into the structure to be concreted. Each method of transportation has its rational areas of application. For low-rise construction characterized by small volumes, scattered construction sites, insufficient coverage by a good-quality road system, and a long distance from concrete factories, it is expedient to use alternative, non-dedicated to concrete mix transportation, types of vehicles equipped with their own lifting devices. The issues of application of drop-side lorries with crane manipulators and gantry hopper trucks for transportation of ready-mix buckets are discussed. The technical characteristics of general purpose vehicles and lifting equipment are described. Recommendations concerning fitting of various types of vehicles with portable hoppers are given.

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Lime plaster is widely used in new construction, repair and restoration works. The most common are plaster mortars based on killed lime. However, mortars based on ground unkilled lime might be preferable in some cases. They are characterized by fast setting and strength development; intensive heat emission during unkilled lime hydration makes it possible to carry out work at low temperatures. The paper discusses properties of compound plaster mortars based on ground unkilled lime. The dynamics of temperature and fluidity depending on time have been analyzed for different compositions, as well as mortar compression strength dependence on hold duration before usage for work, and time curves of mortar strength depending on the water to lime relation. To clarify requirements to the physical properties of mortars for mechanical applications, mortar fluidity and temperature were measured during mortar transportation in a mortar pump.