Техническоe состояние сборных балочных перекрытий с применением керамзитобетонных пустотных плит

A Belousov,A Dronov,E Smolyago,G Smolyago,S Drokin,S Pushkin,А Белоусов,А Дронов,Г Смоляго,Е Смоляго,С Дрокин,С Пушкин

doi:10.34031/2071-7318-2019-4-11-35-42

Abstract

The use of expanded lightweight concrete for the production of building structures can significantly reduce the weight, which is important in the manufacture of hollow-core slabs; the weight is a significant proportion of the total load. In the current regulatory documents, the physical and mechanical properties of expanded lightweight concrete differ significantly, and sometimes contradict each other. The defects and damages of expanded lightweight concrete hollow-core slabs are described in the case of the kindergarten built near 50 years ago. They appeared during the manufacture of the slabs - uncompacted concrete and uncovered ribs, or in the course of exploitation of the building - normal cracking, holes for pipes and corrosion of reinforcement. Two slabs in emergency condition have numerous longitudinal and shear cracks and chips of concrete caused by overloading. The differences in normative documents and methods of calculations used at the time of designing the kindergarten building and at the present time are shown. The assessment of the technical condition of the expanded lightweight concrete hollow-core slabs considering defects and damages are carried out

Highlights

The use of expanded lightweight concrete for the production of building structures can significantly reduce the weight, which is important in the manufacture of hollow-core slabs; the weight is a significant proportion of the total load
The defects and damages of expanded lightweight concrete hollow-core slabs are described in the case of the kindergarten built near 50 years ago. They appeared during the manufacture of the slabs - uncompacted concrete and
Ключевые слова: expanded lightweight concrete, hollow-core slab, durability, defects, strengthening

Summary

Introduction

Использование керамзитобетона для производства строительных конструкций позволяет значительно снизить их вес, что важно при изготовлении многопустотных плит перекрытий, собственный вес которых составляет значительную долю от общей нагрузки. На примере здания детского сада, эксплуатируемого около 50 лет, приведены выявленные дефекты и повреждения керамзитобетонных многопустотных плит перекрытия, появившиеся как при изготовлении плит (участки с неуплотнённым бетоном, непробетонированные ребра плит между пустотами на отдельных участках), так и в процессе эксплуатации здания (нормальные трещины в середине пролета плит, неоформленные отверстия под коммуникации, коррозия арматуры). При использовании керамзитобетона в конструкциях перекрытий, как правило, применяют класс бетонов по прочности на сжатие В15–В30, марки по плотности D1200 – D1800.

Results

Conclusion