TECHNOLOGIES IN THE CONSTRUCTION PROCESS ASPECTS OF SELECTING THE TECHNOLOGIES TIME-SEQUENCE OF THE CONSTRUCTION WORKS

Transcription

1 0 Aspects of selecting the technologies TECHNOLOGIES IN THE CONSTRUCTION PROCESS ASPECTS OF SELECTING THE TECHNOLOGIES TIME-SEQUENCE OF THE CONSTRUCTION WORKS Technologies in the construction process BUTE Faculty of Architecture Department of construction technology and management István Vidovszky PhD Basics of construction INTRODUCTION Time-sequence of the construction works TECHNOLOGY influencing factors DEF: Construction technology is the sum of all work processes of a work activity. The know-how of the construction. cost estimation selection of technology time sequence of construction works

2 ASPECTS OF SELECTION COST ESTIMATION technical circumstances cost required time -> cost workability / viability requirements in equipment / tools = What tools /equipments are at the contractor s immediate service? / What has to be hired? cost of the technology costs of the materials used cost of the time additional costs e.g. - scaffolding TIME ESTIMATION THE PHASE OF THE PLANNING workability / viability time of the work activity required time of the technology costs depending on time e.g. AAC / clay block workable / viable details optimal choices of technology based on local human sources details considering the expected (expectable) accuracy of the local construction industry

3 Technologies in the construction process Harmonizing foundation levels Influencing factors necessary depth of excavation pit construction of substructures construction of superstructures finishing works (+ electric wireing and building installation works) gardening, etc. foundation level of the neighboring buildings foundation level of the constructed building characteristics of the soil Options placing subsequent strip foundation under an existing building slurry wall jet grouting injecting pile-wall Selecting foundation type pile drilled / prefabricated load of the building load bearing capacity of the soil type of the soil (loose/dense) slurry wall slurry pillar strip foundation slab foundation horizontal structures (slab) formwork reinforcement concrete placement work sequence Vertical structures (wall, pillar) reinforcement formwork concrete placement Drilled piles, slurry wall concrete placement reinforcment

4 Concrete supply In-situ concrete influencing factors: cost, time, owned equipments, required quality, etc transport concrete Concrete placement influencing factors scale of the concrete work with concreting pump with concreting bucket Formwork system for horizontal structures modular tables (pre-assembled) work speed <-> flexibility panelized slab drophead formwork system work speed <-> flexibility girder slab formwork

5 Formwork system for vertical structures Formwork system special solutions for vertical structures metal panel formwork wall formwork system girder wall formwork system (single faced < > double faced) pillar formwork climbing wall formwork system sliding formworks self climbing systems No crane is needed! circular wall formworks Masonry Masonry Bricks and blocks - materials AAC*block ceramic bricks - facade bricks *autoclaved aerated concrete / porobeton clay blocks high accurancy clay blocks lime-sand bricks and blocks Steps of technology set up the first course (dimensions, water level, etc.) laying the second, third, etc. courses jointing / grouting surface Surface treatment (depending on the accuracy) high accurate clay blocks, AAC blocks clay blocks thin plaster layer + undercoat +painting (coating),5cm plaster + undercoat +painting (coating) joints Brick surface cleaning the surface finishing the joints recessed /raked flush half-round

6 Masonry Masonry Brick wall bond types Wall types brick walls single or multi unit course block walls single unit courses stertched /running bond heading bond Dutch bond English bond crossbond Flamish (Polnish) bond wider walls Material Structure types traditional structure modern structures timber glued laminated timber (GLT) cross laminated timber (CLT) plywood etc. technology timber (rafters, beams, planks, battens) traditional timber joints (+wrougth iron) in-situ (on site) different materials (timber and/or modern ones) differnet joints mainly with screws, nails, metal sheets, etc. partially or totally prefabricated

7 Traditional - joints Traditional - joints notched, double nothched, housed, cogged, saw cogged, halved, bevelled halved, dovetailed halved, keyed, wedged birdmouth wedged tenon wedged housed stab tenon tenon- mortised bridled Traditional advanced joints Modern joints cleated (with strap) cleated (with dog) mounted with metal (wrought iron) elements cleated (with stub tenon) tusk tenonned strapped, lapped gang nail plates posi-struts

8 WORK ACTIVITY 3 The time of the construction activity DEF: Basic element of the construction. Closed technological interval. during an unbroken interval one trade at the same place TIME-SEQUENCE time of the activity required time the following activity 3 Time-sequence of the construction works 3 Total time of the construction a a b c d e f of a certain construction all the required time of the activities in case of a certain construction TIME-SEQUENCE depends on various things there are many possibilities IMPORTANT = the technical feasibility of the sequence interior plaster fitting windows exterior plaster fitting windows exterior plaster interior plaster exterior plaster fitting windows interior plaster interior plaster exterior plaster fitting windows DEF.: TIME SEQUENCE = The right order of the activities. TIME-SEQUENCE optimal interval optimal cost possible rational or emotional limits of the construction technical limit of the construction increasing costs physically impossible

9 S SOURCES Smiths C. R. Anders K. C.:Principals and practices of heavy construction, Prentice-Hall, Englewood Cliffs, New Yersey, 986. p.40 Ambrose, James: Building Construction. Enclosure System. New York, Van Nostard Sources