Experimental study of early-age behavior of high performance concrete deck slabs under different curing methods

Curing techniques and curing duration have crucial effects to the strength and durability of concrete. Proper curing can protect against moisture loss from fresh concrete. The objective of this experimental study is to examine the early-age behavior of high-performance concrete (HPC) under various curing methods. Laboratory experiments were conducted to investigate the early-age shrinkage development, temperature change, and evaporation rate when different curing methods were used. Four curing techniques and two curing durations were applied to concrete deck slab and cylindrical specimens. The measured experiment data were also compared with several shrinkage prediction models. The results show that proper moisture-curing methods can effectively reduce concrete temperature due to hydration heat and limit the development of early-age shrinkage strains. The concrete of a longer curing duration would yield lower shrinkage deformation and lower evaporation rate.     

水性树脂体系中二氧化硅消光剂的评价及应用

在几个水性树脂体系中,对典型的气相二氧化硅消光剂和沉淀法二氧化硅消光剂的消光性能进行了评价实验,结合物性分析和消光原理对实验结果和二氧化硅消光剂的应用技术进行了探讨,结论对于二氧化硅消光剂的选择和应用具有指导意义。     

光伏光热建筑一体化对建筑节能影响的理论研究

对光伏光热建筑一体化(BIPV／T)的两种主要模式建立了理论模型，采用香港地区典型年的气象数据对两种BIPV／T模式的热性能进行了计算分析。与常规建筑相比，光伏光热建筑减少了墙体得热，改善了室内空调负荷状况，提高了建筑节能效果。     

块体理论赤平解析法及其在硐室稳定分析中的应用

块体理论是近十几年来发展和完善起来的一种适合于裂隙岩体稳定性分析的行之有效的工程方法，裂隙岩体中硐室周围岩体滑落与岩体弱面分布及其力学性质密切相关，其滑移方式对于硐室维护具有重要意义。本文运用所建立的块体理论赤平解析法分析了某矿卷扬机硐室的稳定性，确定了失稳的块体，并指出可采用锚杆加固的措施。     

大跨度悬索桥地震反应分析及其抗震性能评价

对一座大跨度悬索桥进行了地震反应谱分析和线性、非线性的地震时程分析,并在此基础上对该桥进行了抗震性能验算.反应谱分析考虑了周期和阻尼比调整,时程分析时考虑了地震动空间变异性的影响,非线性分析考虑几何刚度变化、大位移以及梁柱效应的影响.抗震性能验算分为强度验算和位移验算.     

关于分形理论在结构岩体的应用研究

介绍了近年来分形几何理论在结构岩体应用研究的最新进展，并简要讨论了目前研究存在的问题。     

大体积混凝土温度裂缝的控制

大体积混凝土施工过程中,原材料的选用、配合比的确定、混凝土内部及表面的测温、降温和保养等几个方面应严格把好质量关,这样才能将大体积混凝土的内外温差控制在规范允许范围之内,避免混凝土温度裂缝的产生。     

钢铁工业冷却水水源热泵的技术应用分析

钢铁工业的冷却水含有大量的低温热量,可以通过水源热泵利用这部分热量实现区域供热。介绍了一些钢铁工业冷却水水源热泵的应用情况,分析了工业冷却水水源热泵的运行费用和投资费用及提高供水温度和制热效率的方法。     

Performance of the Burwarton Estate Waste Stabilization Ponds

The Burwarton Estate waste stabilization ponds, near Bridgnorth, Shropshire, serve a population of 150. There are three ponds in series: a facultative pond, and two equal maturation ponds, followed by two parallel and alternately used constructed wetland ditches. This paper describes the design of the ponds and reports upon their performance during the first two years of operation.