STRENGTHENING THE FOUNDATIONS OF PHYSICALLY OBSOLETE BUILDINGS

The problems and prospects of existing methods of strengthening the foundations of physically obsolete buildings are outlined, which is relevant for the preservation of buildings of architectural and historical value, as well as for mass renovation in large cities in cramped conditions with a high density of existing buildings. Method of calculation of hollow rectangular and round sections filled with concrete during bending is considered. In this article the dependence of compacted zone radius on initial characteristic of soil density and diameter of pressed pipe concrete element is analyzed. The conclusion is formed that the method of arrangement of the pipe-concrete horizontal distributor for simultaneous reinforcement of soil of the base and foundations chosen for the study allows to regulate the process of leveling the building settlement as a whole, and is also the most environmentally safe and does not negatively affect the surrounding buildings and structures.

Fitoremediasi Logam Seng (Zn) Menggunakan Hydrilla sp. Pada Limbah Industri Kertas

Logam seng pada konsentrasi tertentu dapat terakumulasi di dalam air, biota dan sedimen pada perairan yang dapat menimbulkan efek toksik terhadap organisme sehingga untuk mengatasi permasalahan tersebut telah dikembangkan teknologi alternatif yang dikenal dengan fitoremediasi. Tujuan dari penelitian ini adalah memanfaatkan Hydrilla sp. sebagai agen fitoremediasi untuk menurunkan konsentrasi logam seng (Zn) pada limbah industri kertas. Tahap penelitian meliputi uji karakteristik awal air limbah dan Range Finding Test (RFT), penyiapan 75 g Hydrilla sp. dan aklimatisasi Hydrilla sp. selama 5 hari. Hydrilla sp. ditumbuhkan pada reaktor selama 18 hari dalam 5 liter limbah industri kertas dengan konsentrasi 100% dan 5 liter akuades sebagai kontrol (0%). Variabel pengamatan meliputi pengukuran nilai pH, suhu dan identifikasi perubahan warna daun Hydrilla sp. Limbah hasil fitoremediasi pada waktu pemaparan 3, 6, 9, 12, 15, dan 18 hari dilakukan analisis logam seng (Zn) dengan ICP-OES. Berdasarkan hasil analisis menunjukkan bahwa pada hari ke-0 sampai hari ke-12 persentase logam seng yang hilang sebesar 50% dan pada hari ke-18 mengalami penurunan persentase sebesar 25%. Kata kunci : Fitoremediasi, Hydrilla sp., limbah industri kertas, logam seng. Zinc metal at certain concentrations can accumulate in water, biota, sedimentary in waters which can cause toxic effects on organisms. So as to overcome these problems alternative technologies have been developed known as phytoremediation. The purpose of this research is to utilize Hydrilla sp. as a phytoremediation agent to reduce zinc metal concentrations in paper industry wastes. The research phase included preliminary research that is initial characteristic of wastewater and Range Finding Test (RFT), preparation of 75 g of Hydrilla sp. and Hydrilla sp. acclimatization for 5 days, then Hydrilla sp. grown on reactor for 18 days in 5 liters of paper industry waste with 100% concentration and 5 liters of akuadest as control (0%). Observation variables include measuring pH values, temperature and identify discoloration of Hydrilla sp. leaves, then the phytoremediation waste at exposure time of 3, 6, 9, 12, 15 and 18 days was analyzed zinc (Zn) with ICP-OES. Based on the analysis results show that on days 0 to day 12 the percent amount lost by 50% and on the 18th day the amount of zinc metal lost decreased by 25%. Keywords : Phytoremediation, Hydrilla sp., paper industry waste, zinc metals.

To a question of definition of deformation of frosty heaving of soil of road designs by different methods

The article notes the relevance of the issues of ensuring frost resistance of structures, including road, in connection with the almost universal spread of the phenomenon of frost heaving in the territory of the Russian Federation. The question of known methods for determining the calculated characteristics of frost heaving of the soil, which is the initial characteristic of the calculation of structures for frost resistance, is considered. These methods include the standard method, the method VGU in two variants and the method ROSDORNII Institute. These methods are presented in the form of a flowchart with a detailed description of the individual blocks. The shortcomings of the normative method, which lead in some cases to unacceptable errors for engineering practice, are noted. The VGU method in the first embodiment is based only on the use of laboratory test data and plotting the intensity of frost heaving. In the second variant of the VGU method, the character of the intensity plot is taken on the basis of data from long-term field tests.