Methods for organizing flow in construction production. Parallel construction method. Scheduling and Thread Management
The flow method is a progressive method of organizing construction production. The essence of the flow method is to organize sequential, continuous and rhythmic production of construction work, which makes it possible to effectively use material and labor resources. The flow involves producing certain volumes of construction products at equal intervals and increasing the profitability of construction. Experience shows that when switching to " flow"Construction duration is reduced by an average of 20%, labor productivity increases by 8-10%.
With the flow method of organizing construction the construction process is divided into separate components and operations, the implementation of which is entrusted to separate integrated teams or specialized units. These teams or units move evenly from one occupation site to another along the entire work front, and at each site construction processes are sequentially carried out in strict accordance with their technological order. Each team, finishing work on its assigned area, prepares the area for a new cycle of work to be performed by the next team.
At each site, work cycles follow in the established order, which allows for maximum combination of work in time, performing them at the pace provided for by the construction and installation work schedule.
Uniform movement of workers from one grip to another is possible only if the number of workers in teams and units remains constant, and the grips are equal in labor intensity to the work performed.
When organizing construction using the continuous method, the construction of a building is usually divided into the following cycles: preparatory, zero, construction of the above-ground part, finishing work.
The flow method is complemented industrialization of construction, i.e., the continuous transformation of the construction process into a mechanized process of continuous assembly of buildings and structures from factory-made structures.
In construction practice, for planning and managing construction flows, construction processes are modeled using their graphical representation: line graphs and network graphs are developed.
In accordance with the Instructions for the development of projects for the organization of construction and production of works for the construction of complex facilities, enlarged network diagrams are drawn up. This need is explained by the presence of complex relationships between individual units and the farms that serve them.
Network diagrams are a graphic reflection of construction technology. A distinctive feature of a network diagram is a clear relationship between activities with a strict technological sequence of their implementation.
Each network diagram has a starting event (the start of work), intermediate events (the fact of the completion of one or more works), and an ending event. Each “event” occurs at a certain point in time and is indicated on the graph by circles and a serial number. Between events there is a process of work that requires an investment of time and resources. Activities on the network diagram are indicated by arrows, and their duration (in days) is indicated under the arrow.
All intermediate events and related work are located on the network diagram between the initial and final events in accordance with the order of their implementation: some of them are technologically dependent, others are independent, i.e., they can be executed in parallel.
It should be noted that there are two more types of connections between events: " expectation" requiring only time (e.g. drying plaster, curing concrete), and " addiction", which requires neither time nor resources, but only compliance with consistency in the execution of work. Expectation is indicated on the graph in the same way as work - with a solid line, dependence - with a dotted line.
The change of events that are interconnected by work recorded on the graph is called " by". The network of paths diverges from the initial event and converges to the final event. The duration of each path is determined by summing the duration " lying"works on it. The longest path in time between the initial and final events, which determines the completion date of the construction of the object, is called the critical path.
The figure shows, as an example, a fragment of a network diagram for the construction of a one-story warehouse building. The building is divided into three sections. Excavation work, installation of monolithic foundations, delivery and preparation of prefabricated elements for installation, and installation of structures are carried out on parallel streams.
According to the schedule, the main work on the installation of structures (event 7) can begin after the completion of preparatory work 1-2, as well as excerpts of foundation pits on the first block 2-4, installation of monolithic foundations 4-6 and completion of concrete hardening in foundations 6-7. Work 6-7 is actually an expectation, since the process of hardening concrete in foundations requires little resources, but this requires a certain time for the strength of concrete to increase. In addition, the start of installation (event 7) can begin after completion of work 1-3, i.e., delivery and installation of the crane for laying out elements and 3-5 - laying out and preparing for installation of structures on the first grip. Jobs 5-7 and 9-11 are dependencies.
The name and composition of the work shown in the network diagram (Fig. 14.1), their duration in days are indicated in table. 14.1. 
The duration of the paths for the work outlined on the network diagram is calculated in table. 14.2. 
The longest, i.e. critical path, will be path No. 1, lasting 122 days. This “path” determines the duration of the entire complex of work on the construction of the building.
Calculation of the critical path allows you to compare the total duration of construction work with a given period or with the standard construction duration. If the “critical path” turns out to be longer than provided for by construction duration standards, then reserves can be used to reduce the overall construction period due to non-critical work. In this case, the duration of “non-critical” work is extended within the identified time reserves, and the released resources are used to speed up work on the “critical path”.
The organization of construction production involves the following areas of scientific and industrial activity: construction organization, construction planning and construction management.
Construction organization is a system for forming or selecting a production enterprise (complex of enterprises) designed to complete a given task.
Planning is a system for linking ongoing construction and installation work in time and space, as well as a system for the supply and consumption of material and technical resources.
Management is a system for maintaining the established order or transferring construction production from one state to another with the aim of unconditionally completing the assigned task.
The construction of any building or structure of external water supply and sewerage networks and other engineering structures is associated with the production of a complex of construction processes by workers of various professions and different qualifications. Construction processes can be carried out continuously or with certain technological breaks. Thus, when laying external sewer networks with socket joints of individual pipelines, before hydraulic testing, a certain time is required for the cement mortar to harden in the socket joint. The hardening time of the solution in this complex process constitutes a technological break. Technological breaks determine more difficult conditions for organizing a continuous production process.
Construction processes can be started and completed at all sites simultaneously. In this case, the construction time of all objects will be equal to the construction time of one object, however, significant material and technical resources will be required. This method of conducting construction and installation work is called the parallel method.
The flow method of construction and installation work combines sequential and parallel methods, preserving the advantages of both methods and eliminating the disadvantages of each of them separately.
Depending on the configuration of construction projects and its influence on the organization of the flow method of construction, a distinction is made between flow-linear and flow-grabbing methods of work. The linear flow method is used in the construction of extended structures, which include external networks of water supply and sewerage systems. The flow-grabbing method is rational for the construction of buildings and structures for various purposes, with significant dimensions in height; are divided into single- and multi-tiered.
In construction, a complex flow is organized, consisting of specialized (private), object and complex flows. The products of the flows are: specialized - completed volumes of certain works; object - completed buildings and structures; complex - a group of buildings or structures.
Most production processes (not only construction) can be represented in the form of drawings, diagrams, graphs, tables, etc., which quite accurately reflect the reality of what is happening in these processes. These are models of the production process taking place.
Flow organization of construction
If it is necessary to build several objects of the same type, then, depending on the adopted optimization criterion, the work can be organized by three methods - sequentially, parallelly and in-line.
The sequential method allows us to limit ourselves to the minimum number of workers, mechanisms, and the minimum rate of resource consumption, but it will result in the maximum duration of work.
The parallel method, on the contrary, ensures the minimum duration of work, but it requires the maximum number of workers, mechanisms, and the maximum rate of resource consumption.
In practice, in most cases, both methods are undesirable: the first because of the long duration, the second because of the large number of workers and mechanisms. The first method is used only when the capabilities of a construction organization are extremely limited, for example, when there are large restrictions on the provision of investments. The second method is usually used in extreme conditions, when there are roads every day, for example, when eliminating accidents or the consequences of natural disasters. In most cases, the most effective is the third - in-line method. Objects (captures) are rhythmically included in the work and also rhythmically completed. Work at each site (capture) is divided into separate stages, performed by different teams.
The composition of the teams is selected in such a way that the duration of their work at each object (capture) is as equal as possible (failure to comply with this condition does not exclude the use of the flow method, but complicates it, which will be discussed below). Each team moves from object to object (from capture to capture), performing approximately the same work and preparing the work front for the team following it. The team's sequential passage of all objects (occupations) is called the work flow. A flow most often includes work of one type, for example, it could be a flow of excavation work, a flow of work on the construction of foundations, the construction of walls, the installation of floors, etc. However, it is also possible to design complex type flows, i.e. including a variety of work related to any structural element of a building or structure. Moreover, the products of a stream do not necessarily have to be individual structural elements; the stream can cover both a narrower and a wider range of work. This can be, for example, a separate process (installation of formwork, installation of reinforcement, concreting) and, on the contrary, it can be buildings or structures and even groups of buildings or structures (residential areas, drainage systems of individual farms, etc.).
Construction using the flow method involves sequential flows. An analogue of the flow method in construction is a conveyor system in a factory, but in a conveyor system products move, and the performer remains in place; in the flow method, on the contrary, performers move, but the products remain in place.
Design of continuous construction includes determining the rhythm and step of the flow, determining the number and size of teams, mechanisms, estimating the total duration of construction and the completion date of the first object (occupation). Currently, computer programs have been developed to automate the solution of such problems. They are usually included in computer-aided design systems in the form of specialized modules.
The simplest is to design rhythmic flows. With non-rhythmic flows, design becomes significantly more complicated, especially when the rhythms are not multiples of each other. In such cases, the rational solution is usually to increase the steps of the individual streams, which adapt to the variable rhythm. In these cases, teams do not arrive at the object (capture) immediately one after another, but with some breaks. During these breaks, no one works at the site (capture), but the teams themselves do not have breaks in their work.
The flow method is a method of organizing construction that ensures the systematic, rhythmic production of finished construction products based on the continuous and uniform work of work teams of the same composition, provided with timely and complete delivery of all necessary material and technical resources.
Conditions of use:
Quite a large amount of work
Dividing the construction process into stages of work
Purpose of a strict technological sequence
Use of highly specialized teams
Establishing a uniform rhythm in work.
All resources must be used constantly and continuously.
The composition and number of brigades should remain constant for a sufficiently long period of time
Stream parameters:
I. Timing parameters.
1) The total duration of work is T0.
2) The total duration of work on one gripper is TZAHV.
3) Duration of work of the team - TBR
4) Rhythms – ki
5) Technological breaks - tTECH
6) Organizational breaks - tORG.
II. Spatial parameters.
1) The work front is a part of the facility that is necessary and sufficient to accommodate workers with mechanisms and devices.
2) Plot – part of the work area allocated for a team or one worker.
3) A grip is a part of an object, a structural element on which performers of a private or specialized flow are occupied.
Min. the size of the grip is the shift productivity of the team.
4) Tier - part of the object obtained from vertical division according to the technical conditions of the work.
III. Technological parameters. (Number of private, special and object threads).
IV. Organization parameters.(1. Number of types of work 2. Number of pairs of threads)
V. Stat. options. (Scope of work – V, Labor-intensive – QCHDN, cost – C)
VI. Dynamic (number of workers – NPERSON, output of workers per day – Kvr, flow intensity in natural units of measurement – J.
The flow can be represented graphically as a line graph or cyclogram.
The network model is depicted as a graph consisting of arrows and circles. The network diagram represents the network model with calculated timing parameters. The construction of a network is based on the concepts: work and event.
Work is a production process that requires time and material resources and leads to the achievement of certain results.
Waiting is a process that requires only time and does not consume any material resources.
Dependency – is introduced to reflect the technological and organizational relationship of work and does not require either time or resources.
An event is the fact of the completion of one or more tasks, which is necessary and sufficient for the start of the next ones.
A path is a continuous sequence of works in a network diagram.
The critical path is the complete path that has the greatest length of all complete paths.
5. Types of construction flows
I. By type of final product.
1) A private thread is an elementary construction thread consisting of one or more processes. performed by one team, unit or team. Products of a private flow are a separate type of work (for example, earthworks).
2) Specialized flow - consists of a number of particular ones, united by a single system of parameters, a flow diagram. The products of the flow are the structural parts of the building (underground part). The peculiarity is that various specialized teams can work on one grip.
3) Object flow – a set of specialized ones. Products – fully completed buildings or groups of buildings.
4) Complex flow - consists of object flows as part of industrial enterprises, complex development of microdistricts. Products – commissioned industrial. object, completed residential quarter, microdistrict.
28,29. Schedule plans in construction.
Calendar plans. Purpose and principles of development. Types of calendar plans as part of PIC and PPR
Schedule plans in construction include all planning documents in which, based on the volume of work, the sequence and timing of construction are determined.
In accordance with the construction calendar plans, supply calendar plans are developed - schedules of the need for labor and material and technical resources.
The schedule plan for the production of work on an object in the form of a linear or network schedule is intended to determine the sequence and timing of individual types of work; it is used to calculate the time requirement for labor and material and technical resources, as well as the delivery time of equipment.
Development order: 1) Drawing up a list of works 2) determine the volume of work 3) select methods for performing the main work and driving machines 4) calculate standard power and labor intensity 5) determine the composition of brigade units 6) identify the technological sequence of work 7) establish shifts of work 8) determine the duration of individual works and their combination with each other 9) compare the calculated productivity with the standard 10) based on the completed plan, develop schedules for the need for resources and their provision.
The initial data for the calendar plan in the PPR are: 1) calendar plans as part of the PIC 2) construction duration standards or directive assignments 3) technological maps for construction, installation and special works 4) working drawings and estimates 5) data on participating organizations.
Consists of 2 parts: the left one is calculated, the right one is graphical.
Estimated: 1) List of works 2) Scope of work 3) Labor intensity and machine time costs 4) Duration of work 5) Number of shifts 6) Number of workers per shift and crew composition 7) Calculation of crew composition
Design is carried out at the expense of customers, who enter into contracts for the implementation of design work with the general designer.
General designer is an organization that carries out the bulk of design work. Involves specialized design organizations to carry out individual parts of the project (research, special work, etc.) on a contractual basis. At the same time, she is responsible for the complexity of the project.
Scheduling and organization of construction of the underground part of the building
The leading process should be the installation of basement structures. Depending on the design and volume of work, they are divided into grips. It is advisable to have at least 2 grips. This allows you to break down the work and organize its continuous execution.
1) Selection of mounting mechanism. For the zero cycle, it is best to use rail-mounted or crawler-mounted cranes. The pit is excavated using an excavator with a bucket with a capacity of 0.33-0.65 m3.
2) Installation of a) prefabricated foundations is carried out simultaneously with manual removal of the soil b) Pile foundations (a multi-grip system should be adopted, optimally 6: (1) Striker, (2) cutting and preparation of heads, (3) cleaning the base of the grillage, formwork and reinforcement work (4) Concreting (5) curing (6) stripping)
3) Installation and laying of basement walls and partitions.
4) Filling the sinuses of the pit from the inside and backfilling from the inside. This process is planned in schedule II for wall installation.
5) Installation of communications outlets and inputs (sewerage, water supply, heating networks, gas, electricity).
6) Waterproofing of walls, it can be shown in graphics outside the flow.
7) Installation of floors and welding work on them are planned after finishing the concrete floors in the basement.
8) Filling the sinuses from the outside.
10. Composition and content of the feasibility study
The main indicators characterizing the level of design of the organization of construction work include: duration of construction, level of mechanization of main types of work, unit costs of labor, machine time, energy resources and cost of work related to a unit of construction product (for example, labor intensity in man-days per square meter. m of building area, electricity costs kWh per cubic meter of concrete structure, average daily output in monetary terms).
The resulting feasibility studies are analyzed by comparison with the achieved indicators at similar facilities, with advanced domestic and foreign experience.
Construction methods:
Open method (completed zero loop method) i.e. foundations for the building frame are made simultaneously with foundations for equipment and shelves;
Closed method - installation of foundations for equipment and shelves after the construction of the above-ground part of the building under the roof;
Combined - simultaneous installation of building structures and shelves together with the supply and installation of equipment. One specialized thread;
Separate method - performing the installation of building structures in one specialized flow, and installation of equipment (rigging, installation and mechanical installation) - in a specialized flow in a fully constructed building;
Combined method - performing part of the equipment installation work separately from the installation of building structures in the constructed premises.
Methods of organizing construction production. The essence and basic principles of the continuous organization of construction production.
The organization of construction production can be carried out by three methods - sequential, parallel and in-line.
With the sequential method, there are a number of disadvantages - the level of resource consumption is minimal, and the duration of consumption is maximum; each type of resource will be involved for a short time, since the process of building a house periodically requires workers of different specialties, various machines, mechanisms and materials. Machine downtime and losses due to their relocation are also inevitable. Frequent changes in types of materials, products and structures introduce great difficulties into the work of manufacturing enterprises, transport and supply chains.
The parallel method ensures a minimum duration of construction, but the consumption of resources increases many times, the number of workers and mechanisms also increases greatly, which is not always economically feasible.
The flow method, while maintaining the corresponding advantages of sequential and parallel methods, allows one to avoid their disadvantages. With the flow method, the work of constructing each house is divided into n processes. On a complex of N houses, homogeneous processes are carried out sequentially one after another, and heterogeneous processes are carried out in parallel (Fig. 5.3). The duration of construction of N buildings divided into n processes will be longer than with the parallel method, but less than with the sequential method. The intensity of resource consumption here will also be greater than with the sequential method, but less than with the parallel method.
The flow method is characterized by the following features:
1. Division of work into component processes in accordance with the specialty and qualifications of the performers.
2. Dividing the scope of work into separate sections to create the most favorable working conditions for individual performers.
3. Maximum combination of processes over time.
The flow method ensures the uniformity of resource consumption and the rhythm of production of finished products (in this example, houses). The flow organization creates, in turn, favorable conditions for the work of related organizations: contracting organizations, supplier factories, transport, supply operations.
The task of flow design is to determine such parameters that, taking into account rational technology and organization of work, ensure the total duration of construction of the complex within the normative limits and continuous loading of resources (brides, machines, mechanisms).
The organization of production flow in construction provides for:
1. Identification of objects that are similar to each other in terms of volumetric planning and design solutions, and the technology of their construction.
2. Dividing the process of constructing objects into separate works, preferably equal or multiple in labor intensity.
3. Establishing an appropriate sequence of work, connecting interrelated works into a common integrated process and synchronizing them, thereby achieving continuity of construction production.
4. Assigning certain types of work to certain brigades of workers, establishing the sequence of inclusion of individual objects in the flow and the movement of brigades in the process of performing work at individual objects.
5. Calculation of the main flow parameters, taking into account the simultaneous combination of the majority of work and the coordination between the duration of certain types of work and the number of driving machines and work teams.
6. Calculation of the sequence of transition of leading construction teams of workers and machines from site to site, taking into account compliance with the planned rhythm of construction.
For each group of buildings of the same type, a technological sequence of work is established and the rational sizes of areas (areas) and their number are determined. The dimensions of the grips depend on
-mainly on the space-planning structure of the facility, the composition of the equipment, as well as on the nature of the development of specialized flows, the composition of the work they perform and their power (productivity).
An occupation is a part of a building, the scope of work for which is carried out by a team (unit) of a permanent composition with a certain rhythm, ensuring the continuous organization of the construction of the facility as a whole.
The flow method is a method of organizing construction that ensures the systematic, rhythmic production of finished construction products (completed buildings, structures, types of work, etc.) based on the continuous and uniform work of labor collectives (teams, streams) of a constant composition, supplied with timely and complete supply of all necessary material and technical resources.
The use of in-line methods is a natural organizational form for performing construction and installation work using permanent construction teams that are stable in composition and number of workers.
The use of flow methods is determined by the tasks that are set and solved by construction organizations of various levels (briad, site, SU, trust, plant, etc.) in the process of constructing objects for various purposes. All resources in such an organization must be used constantly and continuously. This condition must be ensured for each individual labor resource of the brigade (link) and all the means interconnected with it in the process of work (mechanisms, equipment, etc.).
The composition and number of brigades should remain constant on average for a sufficiently long period of time, even during the construction of heterogeneous objects. This condition ensures both a sustainable increase in labor productivity and the creation of a favorable socio-psychological climate in the team.
Possible periodic partial changes in the set of jobs are compensated by the combination of professions by workers of complex brigades.
28 Classification of flows by structure and type of product, rhythm and duration. Flow parameters: spatial, technological and temporal.
Classification of flow by structure and type of product, rhythm and duration. Flow parameters – spatial, technological and temporal.
Classification of flows is carried out depending on the structure and type of final product.
Private stream- this is an elementary construction flow, which is one or more processes performed by one team (team, unit). The products of a private flow can be excavation work, laying foundations, laying walls, installing a house, plastering work, etc. A private flow is organized mainly where it is possible to perform work on different sections in a flow-dissected manner.
Specialized thread consists of a number of private flows, united by a single system of parameters and flow diagram. Specialized threads are the basic building blocks of a thread. Their products are completed types of work, structural elements and parts of buildings (underground part of the building, roof, finishing work). Depending on the nature of the object, the type and degree of combination of work on the same grip(s), when performing work manually, various specialized flows can work simultaneously, for example, teams of electricians and plumbers during the construction of a residential building. Private and specialized flows can have different directions of division, which depend on the space-planning solution of the building, the types of work performed
and their stages, used construction machines and mechanisms. They can be horizontal, vertical, inclined and mixed (Fig. 5.4).
The horizontal direction of flow is carried out when constructing foundations, installing structures of one floor, roofing work, etc. The vertical direction of flow can be vertically upward, vertically downward, or a combination of these two directions. The vertical scheme is used when installing multi-storey industrial buildings, when installation is carried out using the “crane” method in separate sections for the entire height of the building, when laying pipes in brick, etc.
Using an inclined pattern, one-story brickwork is carried out, structures are installed at different elevations, etc. The combination of different directions gives combined flow patterns. The predominant pattern of flow development in multi-story construction is horizontal-vertical, and in single-story construction it is horizontal.
Object stream- a set of specialized flows, the composition of which ensures the implementation of the entire complex of works on the construction of the corresponding construction project. The products of these flows are completely finished buildings (structures) or a group of buildings (structures). 
Complex flow- consists of object flows simultaneously engaged in the construction of individual buildings and structures that are part of an industrial enterprise, residential area, etc. The products of the complex flow are commissioned industrial facilities, completed residential areas, etc.
The general diagram of the technological structure and flow levels by type of work is shown in Table. 5.1,
The nature temporarilyro development, the following types of flows are distinguished:
1. equal-rhythmic, in which all component flows have the same rhythm, i.e., the same duration of work on all tasks;
2. multiple rhythmic, in which all component flows have unequal but multiple rhythms;
3. heterorhythmic, in which the component flows do not have a constant rhythm due to the heterogeneity of buildings and structures and the inequality of the rates of the component flows.
Flow parameters express temporal, organizational and spatial characteristics and make it possible to determine the dependencies between them.
TO temporary flow parameters include:
T 0- the total duration of work on the flow as a whole;
T l- the total duration of the work flow for the teams to complete all the work in one area;
T br- the total duration of work of each individual brigade on all grips;
t,br- the rhythm of the team’s work, the duration of the team’s work on the capture;
t org- organizational breaks between the work of adjacent teams on the same area;
The experience of industrial production shows that the best method of organizing it is a production flow system characterized by uniformity and continuity of the technological process.
Continuity and uniformity of production are expressed in continuous and uniform consumption of labor and material and technical resources, as well as in continuous and uniform production. This leads to an improvement in all indicators: production is accelerated; with the same production capacity, production output increases; its quality improves; labor intensity and cost of production are reduced.
The principle of continuity and uniformity is also the basis of continuous construction.
The essence of the construction flow can be represented by the following diagram (Fig. 1).
As can be seen from the diagram, if it is necessary to build m identical buildings (to produce m units of construction products), then their construction can be organized using different methods: sequential, parallel, in-line.
The sequential method provides for a work order in which each subsequent building is erected following the completion of the previous one.
The parallel method involves the simultaneous construction of all buildings.
The flow method is a combination of sequential and parallel, in which the disadvantages are eliminated to the greatest extent and the advantages of each of them are preserved. With the flow method, the technological process of constructing a building is divided into n component processes (laying foundations, erecting walls and ceilings, installing a roof, finishing work), assigning the same duration to each of them and combining their rhythmic execution over time on different buildings, ensuring the sequential execution of homogeneous processes and parallel - heterogeneous.
Rice. 1. Comparative characteristics:
a - sequential; b - parallel; c - in-line methods
With the sequential method, the duration m of construction of buildings
and intensity of resource consumption per unit of time
where Tc is the duration of the production cycle for the construction of one building;
R is the total cost of resources for the construction of t buildings.
With the parallel method, production is accelerated: the total duration of construction of m buildings is the duration of one production cycle - Tc, but the intensity of resource consumption increases m times.
Continuous construction of m buildings requires less time than sequential construction (T
Therefore, the flow production method is an effective combination of serial and parallel.
To create a construction flow you need:
1) divide the construction production process into component processes and operations;
2) divide labor between performers;
3) create a production rhythm;
4) combine the execution of the component processes as much as possible in time.
Continuous construction can have different rates: from the slowest to the most accelerated. This depends on the assigned rhythm of production, the number of workers employed, and the number and power of construction machines used. The choice of one or another pace is made taking into account the given pace of construction and the possibility of providing it with labor, material and technical resources.
In some cases, there is a need to construct a building or structure as soon as possible. Then a high-speed method is used, based on carrying out work in the shortest, technically possible and economically feasible time by using the greatest combination of work in time and using the maximum possible day for arranging the number of workers and construction equipment (machines, devices).
High-speed methods, which are appropriate in some cases for the construction of large buildings or structures, often turn out to be ineffective and practically unacceptable due to the significant and short-term intensity of resource consumption, since high-speed construction is mainly based on the principle of parallel production.
The flow-high-speed method, which has the advantages of the tray and high-speed methods, is most widely used in construction. The flow-high-speed construction method is a method of organizing production that ensures the shortest possible work time and is characterized by continuous and uniform consumption of labor, material and technical resources, as well as continuous and uniform production of products with a minimum intensity of resource consumption.
The flow-speed method can be used:
a) in individual construction processes;
b) in the construction of individual buildings;
c) during the construction of a complex of structures (development of a block, village).
In all these cases there is a limited short-term construction flow; a flow object is a process, building or group of plants that is completed within a more or less short period of time, after which production must be rebuilt in connection with the transition to the construction of new facilities.
In contrast to such short-term limited use of the flow-speed method, one should consider its variety - the so-called long-term, or continuous flow. This method is based on long-term flow-speed work of a construction organization of a certain production capacity, capable of efficiently, evenly and continuously using means of production for a long time without reducing productivity and restructuring.
In contrast to short-term, limited flows, where the objects for applying flow are individual construction processes, buildings or complexes of buildings, the objects for creating a continuous construction flow are specialized construction organizations of appropriate production capacity, provided with all types of production resources and design documentation.
- < Prev
- Next >
Parallel construction method
The parallel method involves the simultaneous performance of a number of works on a separate building or the construction of several buildings of the same type. An independent team will work at each of the sites under consideration. Ideally, all teams will begin work at the same time and complete the construction of buildings at the same time. With the parallel method, the total duration of construction of a separate building is equal to the time required to complete all work, but at the same time the need for workers for simultaneous work will increase several times.
The parallel method ensures a minimum duration, since the construction period is equal to the construction period of one house. However, here, just as with the sequential method, the type and quantity of resources consumed constantly changes depending on the construction period.
But the modern level of construction production and construction organization, when construction and installation work is mainly carried out by powerful contracting general construction organizations, excludes the use of sequential and parallel construction methods in their pure form. This is primarily due to the need for uniform use of resources (machines, work teams, etc.), as well as the limitations of these resources.
For example, during the construction of any facility, as work is completed in a certain technological sequence, mechanisms and crews that have completed work at a certain stage are released. So, first, earth-moving equipment is freed up, then installation teams, installation cranes, etc. In order for these capacities not to be idle, they must be switched to the construction of another facility. Thus, certain work begins at the second object, and at the same time ends at the first, etc.
When performing work on many objects simultaneously during certain periods, the need for homogeneous resources may significantly exceed their actual availability. Therefore, as work on one site is completed, these resources will be sequentially transferred to another, etc.
The flow method, while maintaining the corresponding advantages of sequential and parallel methods, avoids their disadvantages. With the flow method, work on the construction of each of the houses is divided into several processes, the completion of which is allotted the same amount of time. On a complex of N houses, homogeneous processes are performed sequentially one after another, and heterogeneous processes are performed in parallel. The duration of construction of N buildings divided into several processes will be longer than with the parallel method, but less than with the sequential method. The intensity of resource consumption here will also be greater than with the sequential method, but less than with the parallel method.
