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摘  要

我國是世界上純堿年產(chǎn)量最多的國家，占世界總量的1/3以上?，F(xiàn)階段，國內(nèi)純堿生產(chǎn)多數(shù)采用氨堿法，占純堿總產(chǎn)量的60%以上。但是氨堿法制堿過程產(chǎn)生大量的副產(chǎn)物（堿渣），長期下來大量堆積形成的“堿渣山”占地面積大、極易起塵，嚴重影響了群眾的正常生活及地區(qū)環(huán)境，而且不能自行凝固，在地震等外因素作用下，還可能出現(xiàn)塌方和大滑坡?，F(xiàn)如今土地資源凸顯緊缺，可供堆放堿渣的灘涂、洼子已不復存在，因而急需研究堿渣田合理處置、再利用方法。

目前國內(nèi)對于堿渣的處理有堿渣回填造地、筑壩填埋、吹填貯放以及作為土壤改良劑等，但是對于大規(guī)模堿渣的有效處理方式則是將堿渣作為堿渣固化土來利用，堿渣固化土是在堿渣土中加入固化劑混合料形成的特殊工程用土，用于填筑工程。然而堿渣具有高含水量、高壓縮性、失水性差、強度低、孔隙率小等特點導致對其處理一直存在很大的困難。本文以天津港北疆港區(qū)堿渣為研究對象，通過一系列的室內(nèi)試驗對高含水率堿渣的固化改良技術做了系統(tǒng)的研究，以及提出了堿渣田就地淺層固化快速形成施工便道等技術，主要內(nèi)容和結論如下：

（1）根據(jù)相關的研究經(jīng)驗，結合堿渣的特點，考慮經(jīng)濟性以及實用性，選擇固化劑組成成分，分別為高爐礦渣微粉（GGBS）、水泥。

（2）開展GGBS單一固化試驗以及水泥單一固化試驗，分別從不同摻量、不同養(yǎng)護齡期下的無側限抗壓強度進行比較分析。試驗結果表明：當采用單一GGBS進行固化時，堿渣固化土的早期強度大于相同水泥摻量下的早期強度，但GGBS在較高摻量下，堿渣固化土后期強度發(fā)展變緩。

（3）基于對單一固化劑固化效果以及經(jīng)濟性考慮，開展復合型固化劑試驗，分別從不同摻量、不同養(yǎng)護齡期下的強度進行比較分析。采用模糊數(shù)學分析方法，確定3%水泥+8%GGBS的固化劑配比為本試驗所取原狀堿渣的優(yōu)選配比。

（4）開展優(yōu)選配比下堿渣固化土的一維壓縮試驗，研究堿渣固化土的壓縮變形特性和結構屈服應力等工程特性。結果表明，堿渣固化土經(jīng)過28d養(yǎng)護后達到了中壓縮性土的標準，但是當荷載超過堿渣固化土的屈服應力時，其壓縮系數(shù)將出現(xiàn)陡增。

關鍵詞：堿渣；GGBS；優(yōu)化研究；無側限抗壓強度；壓縮試驗；屈服應力 

ABSTRACT

Our country is the world's largest soda residue annual country, accounting for more than one-third of the world total. At this stage, the majority of domestic soda residue production using ammonia soda, accounting for more than 60% of total production. But ammonia soda process produces a large amount of byproducts (soda residue), down to the large accumulation of long-term formation of the "soda residue Hill", an area of large, easy dusting, seriously affected the normal life of the people and the local environment, but can not self solidified in earthquake endures factors may also occur landslides and large landslides. Now highlight the scarcity of land resources, piling up the beach for caustic sludge has ceased to exist, and thus in urgent need of proper disposition of field research caustic sludge, recycling methods.

Currently treatment for soda residue including backfill stretched, damming landfill, reclamation storage and used as a soil conditioner, but for the effective treatment of large-scale is to improve soda residue as stabilized soil to use. Soda residue solidified soil is added to the soil hardener mix with soil formed a special project for the reclamation project. However soda residue with high water content, high compression, poor dehydration, low strength, low porosity and other characteristics lead to its treatment there has been very difficult. In this paper, using the soda residue from Tianjin Port Northern Port for the study through a series of laboratory tests. To do a systematic study on the high moisture content of the soda residue solidification improved technology and propose shallow cured in a caustic sludge field in order to quickly form construction of access roads , the main content and conclusions are as follows: 

(1) According to relevant research experience, combined with the characteristics of soda residue, considered the economic and practical, it selects hardener components:blast furnace slag powder (GGBS) and cement.

(2) By carring out GGBS single test and curing cement single test, it adopts a comparative analysis of different dosage and different curing period unconfined compressive strength.The results show that: when using the single GGBS for curing, soda residue solidified soil early strength greater than under the same cement content, but when GGBS is at higher dosage, the late strength develop slowly.

(3) Based on a single effect as well as economic considerations and carring out the compound type curing agent text. It analyzes different content and the intensity under different curing period. Fuzzy mathematical analysis methods to determine the 3% + 8% GGBS cement curing agent ratio of undisturbed caustic preferred ratio.

(4) By carring out the preferably ratio stabilized soil one-dimensional compression test, study soda residue solidified soil compressive deformation characteristics and structural characteristics of yield stress and other projects. The results showed that after 28d, soda residue solidified soil conservation up to the moderate compression of the soil, but when the load exceeds the yield stress of soda residue solidified soil, the compression factor will appear steep.

Key words：soda residue；GGBS；optimization study；unconfined compressive strength；compression tests；yield stress 

第1章 緒論

1.1 研究堿渣的背景和意義

我國是發(fā)展中國家，天然堿不夠豐富，而純堿又是重要的化工原料。但是氨堿法生產(chǎn)純堿過程中會產(chǎn)生大量的廢渣（堿渣），天津堿廠每年排出的堿渣廢液量就達到 ，其中固態(tài)堿渣為 ，自從建廠以來排放的堿渣已超過1500萬噸[1]，堿渣占地面積大、方量多，常年露天堆放，極易起塵，嚴重影響了群眾的正常生活及地區(qū)新區(qū)環(huán)境，而且現(xiàn)如今土地資源凸顯緊缺，可供堆放堿渣的灘涂、洼子已不復存在。堿渣的大量堆放嚴重影響和阻礙該地區(qū)的開發(fā)、建設和經(jīng)濟發(fā)展，因而對堿渣的研究已經(jīng)引起了高度的重視。然而堿渣具有含水量高、壓縮性大、抗剪強度低、結構性極差、承載能力低等特點，必須進行處理才能滿足相應的道路交通及廠房用地等后續(xù)工程建設的需要。國內(nèi)學者對于堆積年代較久堿渣的處理以及在工程實踐中的應用進行了許多的探索和研究。。。