Restraint effect of partition wall on the tunnel floor heave in layered rock mass

The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the tunnel.This study focused on preparing layered specimens of rock-like material with varying thickness to investigate the failure behaviors of tunnel floors.The results indicate that thin-layered rock mass exhibits weak interlayer bonding,causing rock layers near the surface to buckle and break upwards when subjected to horizontal squeezing.With an increase in the layer thickness,a transition in failure mode occurs from upward buckling to shear failure along the plane,leading to a noticeable reduction in floor heave deformation.The primary cause of significant deformation in floor heave is upward buckling failure.To address this issue,the study proposes the installation of a partition wall in the middle of the floor to mitigate heave deformation of the rock layers.The results demonstrate that the partition wall has a considerable stabilizing effect on the floor,reducing the zone of buckling failure and minimizing floor heave deformation.It is crucial for the partition wall to be sufficiently high to prevent buckling failure and ensure stability.Through simulation calculations on an engineering example,it is confirmed that implementing a partition wall can effectively reduce floor heave and enhance the stability of tunnel floor.

Basic Characteristics of an Appropriate Waste Fillers for Solvent Free and Water-Borne Industrial Polymer Floors and Their Utilization

Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its composition.First tendency to reduce of solvents and diluents contained in the materials appeared at the end of 90´s.This situation was supported by the Council of Europe in 2004 to reduce VOC emissions to zero till 2020.Solvent materials were thus largely replaced by solvent free materials from which the volatile substances are not released into the air.But pressure continued to increase,and over the past decade began to take centre stage water-based epoxy.On the Czech market solvent based material is still occasionally used,but predominant are solvent free materials.There are no commonly used materials containing wastes as fillers in new water-borne and solvent-free epoxy materials.Characteristics identification of the waste material as a potential filler is a set of properties that determine the limits of secondary raw materials or waste as a filler.This paper describes the basic characteristics which must be selected to meet the requirements,to affect negatively the workability,sedimentation,properties and behavior of the final floor system.Some materials must comply with special requirements,such as resistance to chemicals,etc.Next part of paper talks about utilization of polymer floors and their mechanical properties.

Further Analysis of Machine Tool Dimensional Accuracy and Thermal Stability under Varying Floor Temperature

Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s dimensional accuracy. This paper is a continuation of our earlier work, which aimed to analyze the effect of the internal temperature of a machine tool as the machine is put into operation and vary the external temperature, the machine floor temperature. Some experiments are carried out under controlled conditions to study how machine tool components get heated up and how this heating up affects the machine’s accuracy due to thermally induced deviations. Additionally, another angle is added by varying the machine floor temperature. The parameters mentioned above are explored in line with the overall thermal stability of the machine tool and its dimensional accuracy. A Robodrill CNC machine tool is used. The CNC was first soaked with thermal energy by gradually raising the machine floor temperature to a certain level before putting the machine in operation. The machine was monitored, and analytical methods were deplored to evaluate thermal stability. Secondly, the machine was run idle for some time under raised floor temperature before it was put into operation. Data was also collected and analyzed. It is observed that machine thermal stability can be achieved in several ways depending on how the above parameters are joggled. This paper, in conclusion, reinforces the idea of machine tool warm-up process in conjunction with a carefully analyzed and established machine floor temperature variation for the approximation of the machine tool’s thermally stability to map the long-time behavior of the machine tool.

Maxillary sinus floor augmentation: a review of current evidence on anatomical factors and a decision tree

Maxillary sinus floor augmentation using lateral window and crestal technique is considered as predictable methods to increase the residual bone height;however,this surgery is commonly complicated by Schneiderian membrane perforation,which is closely related to anatomical factors.This article aimed to assess anatomical factors on successful augmentation procedures.After review of the current evidence on sinus augmentation techniques,anatomical factors related to the stretching potential of Schneiderian membrane were assessed and a decision tree for the rational choice of surgical approaches was proposed.Schneiderian membrane perforation might occur when local tension exceeds its stretching potential,which is closely related to anatomical variations of the maxillary sinus.Choice of a surgical approach and clinical outcomes are influenced by the stretching potential of Schneiderian membrane.In addition to the residual bone height,clinicians should also consider the stretching potential affected by the membrane health condition,the contours of the maxillary sinus,and the presence of antral septa when evaluating the choice of surgical approaches and clinical outcomes.

Refrigerator Coupling to a Water-Heater and Heating Floor to Save Energy and to Reduce Carbon Emissions

With an aim of rationing use of energy, energy safety, and to reduce carbon emission, our interest was geared towards the refrigerators and all the refrigerating machines. Indeed the heat yielded by the exchanger condenser can be developed for the water heating, floors heating etc. After an encouraging theoretical study, two prototypes were produced in order to validate the theoretical results. A first refrigerator was coupled with a water-heater and another with a heating floor. The water temperature reached, in one day, is of 60℃;which makes it possible to predict better results with a continuously used refrigerator. In the same way for the heating floor coupled with the second refrigerator, the temperature reached high values because the surface is reduced;however for the heating floors the standard fixes the temperature between 28℃ and 30℃.

Minimally invasive techniques for lateral maxillary sinus floor elevation: small lateral window and one-stage surgery—a 2–5-year retrospective study

This study aimed to introduce a minimally invasive technique for maxillary sinus floor elevation using the lateral approach(lSFE)and to determine the factors that influence the stability of the grafted area in the sinus cavity.Thirty patients(30 implants)treated with lSFE using minimally invasive techniques from 2015 to 2019 were included in the study.Five aspects of the implant(central,mesial,distal,buccal,and palatal bone heights[BHs])were measured using cone-beam computed tomography(CBCT)before implant surgery,immediately after surgery(T0),6 months after surgery(T1),and at the last follow-up visit(T2).Patients’characteristics were collected.A small bone window(height,(4.40±0.74)mm;length,(6.26±1.03)mm)was prepared.No implant failed during the follow-up period(3.67±1.75)years.Three of the 30 implants exhibited perforations.Changes in BH of the five aspects of implants showed strong correlations with each other and BH decreased dramatically before second-stage surgery.Residual bone height(RBH)did not significantly influence BH changes,whereas smoking status and type of bone graft materials were the potentially influential factors.During the approximate three-year observation period,lSFE with a minimally invasive technique demonstrated high implant survival rate and limited bone reduction in grafted area.In conclusion,lSFE using minimally invasive techniques was a viable treatment option.Patients who were nonsmokers and whose sinus cavity was filled with deproteinized bovine bone mineral(DBBM)had significantly limited bone resorption in grafted area.

Reporting Children’s Development below the Test Floor: Looking Back and Forth to Describe Individual Strengths and Needs

The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners requested advice on the reporting of children’s development below the floor of the test, so that individual strengths and needs can be described. This paper reports the third phase of research following an earlier Scoping Review and a wider literature review. To confirm quality control, Phase 3 was conducted in a retrospective manner using the same methodology as the earlier phases but in a reverse direction. Peer reviewer comments and key elements from the Scoping Review and keywords from the publications were tabulated. Data analysis included a change of perspective to that of the child and their individual rights with respect to the literature themes already described in Phase 2. These confirmed that there is little specific guidance in the literature, but that computational advances for homogeneous populations and especially disaggregated data offer some solutions. A greater balance between broad biopsychosocial models and standardised models of assessment should be sought by practitioners together with the use of disaggregated data to highlight issues that pertain to individual subsets of results. This will ensure that the child’s right for their individual strengths and needs to be described together with a plan for management, may be met.

Experimental Mode and Vibration Comfort Analysis of High-Rise Glulam Building Floor Structure

In order to better meet the objective requirements of the use safety of the high-rise glulam building floor structure and the living comfort of the residents,the transient excitation,environmental excitation and frequency spectrum identification methods were used to carry out experimental modal test in-site on the three rooms numbered A,B and C of the same glulam structural building.The three rooms have different functions,different floor sizes and different floor supporting structures.The research results have shown that the first-order bending frequency of the floor structure of Room A is 27.50 Hz,the transverse second-order bending frequency is 34.75 Hz,the longitudinal second-order bending frequency is 53.25 Hz,and the first-order torsional frequency is 56.25 Hz.The reinforced wooden beam at the bottom of the floor of Room A increases the transverse stiffness of the floor structure,but does not offset the anisotropy caused by the longitudinally installed glulam floors.The fundamental frequency values of the floor structures of the three rooms numbered A,B,and C are 27.5,13 and 18 Hz,respectively.This has a relatively high innovation and reference significance for integrating the theory of structural dynamic characteristics with the dynamic testing technology,improving the design level of high-rise glulam structure buildings,and improving the living comfort of residents.

Effects of High Risk Pregnancy Factors on Pelvic Floor Muscle Weakness and Changes of PG, ACTH and CRP

Objective: To investigate the effects of different delivery modes on perinatal pelvic floor muscle strength, PG, ACTH and CRP of high-risk pregnant women. Methods: 380 high-risk pregnant women who gave birth in our hospital from March 2021 to February 2022 were selected as subjects, including 100 vaginal natural delivery, 156 forceps assisted delivery and 124 cesarean section. Pelvic floor pressure, PG, ACTH, CRP, IL-6, TNF-α and IL-4, IL-10 levels were evaluated and compared. The perinatal occurrence of pelvic floor functional disease (PFD) in high-risk pregnant women in each group was analyzed and evaluated. Results: There were statistical differences in the amount of postpartum blood loss (P 0.0001, F = 99.01), postpartum blood loss 24 h (P = 0.0004, F = 19.54) and hospital stay (P 0.0001, F = 70.81) among the three groups of high-risk women in natural vaginal delivery, forceps delivery and cesarean section. In addition, there were 72, 134 and 70 cases of abnormal pelvic floor fatigue in natural vaginal delivery, forceps assisted delivery and cesarean section (P 0.0001, χ2 = 30.16). There were 36, 79 and 21 cases of muscle injury, respectively (P 0.0001, χ2 = 34.16). There were 49, 98 and 43 cases of dysmuscular contraction, respectively (P 0.0001, χ2 = 21.94). There were 65, 120 and 41 cases with vaginal dynamic pressure 80 cm H2O (P 0.0001, χ2 = 56.86), respectively. The.

Two Cases of Epidermoid Cyst of the Buccal Floor Simulating: A Tumour of the Submandibular Gland

Dermoid cyst of the oral floor is rare benign tumour, who having three histological aspects: dermoid, teratoid and epidermoid. This one is characterized by the presence of a squamous stratified epithelium with cutaneous remnants. It may occur in any part of the body, however their frequency in the ENT sphere is relatively scarce. Seven per cent (7%) only of epidermoid cysts occur in the cervico-facial area, 1.6% of which locate at the floor level. When they are located submandibular, they can pose diagnostic difficulties and look like a tumour of the submaxillary gland. We report two cases of epidermoid cyst of the floor. Both patients suffered from swelling of the submandibular gland. Magnetic Resonance Imaging was not requested due to lack of resources. However, surgery allowed in both cases the excision of a cyst next to a normal submandibular gland. Patients did well post operatively.

经会阴盆底超声参数对盆底功能障碍性疾病的监测效果及对盆底康复治疗的指导价值

目的探究经会阴盆底超声参数对盆底功能障碍性疾病(PFD)的监测效果及对盆底康复治疗的指导价值。方法选取2021年1月至2022年6月江苏省连云港市妇幼保健院119例产后42 d发现的PFD患者作为研究对象,根据分娩情况分为初产妇组(n=59)和经产妇组(n=60)。比较两组及不同分娩方式患者盆底超声参数,所有患者均行盆底康复治疗,治疗1个月后统计疗效,分析各参数预测疗效的价值。结果经产妇组尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于初产妇组(P<0.05);两组中自然分娩孕妇尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于剖宫产孕妇(P<0.05);疗效不佳的PFD患者治疗前的尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于疗效良好的患者(P<0.05)。治疗前尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)预测PFD患者盆底康复疗效不佳的曲线下面积(AUC)分别为0.821、0.771、0.732、0.703。结论经会阴盆底超声参数可监测PFD病情,且能为临床预测盆底康复疗效、判断疾病转归提供参考。

腹腔镜子宫肌瘤剔除术对子宫肌瘤患者盆底功能、卵巢功能的影响

目的探讨腹腔镜子宫肌瘤剔除术(LM)对子宫肌瘤患者盆底功能、卵巢功能的影响。方法纳入2021年1月至2022年10月濮阳市安阳地区医院收治的80例子宫肌瘤患者,按抽签法分两组。对照组40例行开腹子宫肌瘤剔除术(AM),研究组40例行LM,对比两组手术前后疼痛因子[心肌细胞P物质(SP)、前列腺素E_2(PGE_2)]、应激反应指标[去甲肾上腺素(NE)、皮质醇(COR)]、免疫功能指标(CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))、盆底功能指标[盆底障碍影响简易问卷7(PFIQ-7)]及卵巢功能指标[雌二醇(E_2)、促黄体生成素(LH)、促卵泡激素(FSH)]。结果术后1 d、术后3 d时,研究组血清SP、PGE_2、NE、COR水平低于对照组,差异有统计学意义(P<0.05)。术后1d时,两组CD3^(+)、CD4^(+)及CD4^(+)/CD8^(+)功能指标与术前相比均有所降低,但研究组明显高于对照组,差异有统计学意义(P<0.05);而两组的CD8^(+)功能指标与术前相比有所升高,但研究组明显低于对照组,差异有统计学意义(P<0.05)。术后1个月、术后3个月时,两组PFIQ-7评分均有所升高,但研究组明显低于对照组,差异有统计学意义(P<0.05)。术后3个月、术后6个月时,研究组血清E_2水平高于对照组,而血清LH、FSH水平低于对照组,差异有统计学意义(P<0.05)。结论对子宫肌瘤患者行LM可有效减轻机体疼痛程度、应激反应及对免疫、盆底和卵巢功能的负面影响,优势较为显著,具有进一步的使用价值。

特厚煤层底板断层破坏与顶板垮断联动效应的CFDEM模拟研究

特厚煤层采场空间大、覆岩扰动范围广,顶板垮断产生的强扰动加卸荷载易导致底板断层破坏加剧。通过数值模拟研究特厚煤层底板断层突水与顶板垮断联动效应机理规律是开展水害防治的基础,关键在于掌握加卸载下岩体渐进破坏与裂隙流耦合特征。构建加卸载下拉、剪损伤演化方程,结合有效偏/球应力为基本变量的屈服准则与塑性势函数,得到完整岩块的塑性损伤本构;建立拉/剪、混合型加卸载过程中塑性位移与强度劣化关系,以平方拉剪应力与B-K准则为初始、完全断裂准则,形成非贯通裂隙断裂本构;提出岩块分离、压缩、剪切判据,结合实验数据建立离散块体间挤压、剪切摩擦本构与剪胀方程。基于质量/动量守恒、状态方程,并结合流体体积与浸没边界方法,形成裂隙岩体气−水二相流模拟理论。由此形成CFDEM数值计算程序,并将加卸载下塑性损伤、断裂、挤压/摩擦、流体属性分别赋予实体单元(岩块)、黏聚力单元(非贯通裂隙)、接触对(贯通裂隙)、欧拉单元(水和气)。根据宁武煤田北部矿区工程地质条件,建立特厚煤层底板断层突水与顶板垮断联动效应数值计算模型。结果表明:①CFDEM耦合程序及相应的理论模型可数值实现特厚煤层覆岩及底板断层从(准)连续体到离散体转化,以及地下水在裂隙中运移;②模拟条件下特厚煤层含断层底板的采动裂隙包络线呈w形,最深处超过55 m位于断层及其上盘,最浅处23 m位于断层下盘,而无构造底板处的破坏深度为24~36 m,已导通奥灰含水层;③特厚煤层底板普遍出现二次破坏现象。表现为无构造底板在超前工作面处破坏深度为24.0~29.3 m,但在采空区内普遍增加至31.5~36.0 m;断层及其上盘在超前工作面处裂隙总开度为0.34~0.86 m,但在采空区内迅速增加至3.6 m,形成突水优势通道。④底板断层突水与顶板垮断联动效应的根源在于覆岩高位关键岩层垮断失稳、砌体梁下沉与二次断裂,并导致底板二次破坏,突水风险加剧。

RPG整体姿态康复技术联合盆底电刺激、手法按摩治疗MFPP的临床疗效

【目的】探讨RPG整体姿态康复技术联合盆底电刺激、手法按摩治疗肌筋膜源性慢性盆腔痛(MFPP)的临床疗效。【方法】选取2020年3月至2023年12月在本院盆底诊治中心就诊的80例MFPP的女性患者,采用随机数字表法分为观察组和对照组,每组40例。两组均接受电刺激治疗、手法按摩及盆底肌肉锻炼治疗1个疗程,观察组同时给予RPG整体姿态康复训练。比较两组治疗后有效率及治疗前后盆腔肌筋膜疼痛程度、异常体态改善情况。【结果】观察组治疗有效率为87.50%,与对照组的80.00%比较,差异无统计学意义(P>0.05)。盆腔左侧、盆腔右侧、闭孔内肌、梨状肌、混合性等5个部位疼痛比较,差异均无统计学意义(P>0.05)。治疗后,两组中度、重度疼痛患者占比均较治疗前明显减少(P<0.05),且观察组无疼痛患者占比显著高于对照组(P<0.05)。观察组患者异常体态改善有效率为57.33%,与对照组患者的37.50%比较,差异无统计学意义(P>0.05)。【结论】RPG整体姿态康复技术联合盆底电刺激、手法按摩可显著减轻MFPP患者的疼痛程度,是治疗MFPP安全、有效的方法,长期疗效有待进一步观察。

术前盆底肌电生理参数对前列腺癌根治性切除术后早期尿失禁的预测价值

目的:探索术前盆底肌电生理参数对前列腺癌术后尿失禁风险的预测价值。方法:选择2020年1月至2022年10月在北京大学第一医院泌尿外科行根治性前列腺切除术患者的病例资料进行回顾性分析,记录患者的年龄、体重指数(body mass index,BMI)、国际前列腺症状评分(international prostate symptom score,IPSS)、前列腺特异性抗原(prostate-specific antigen,PSA)水平、Gleason评分、手术方式、是否尿道功能重建、是否淋巴结清扫、性神经是否保留、留置导尿时间、D’Amico风险分级、美国麻醉医师协会(American Society of Anesthesiologists,ASA)评分、查尔森(Charlson)合并症指数、术后随访时间、前列腺体积,以及盆底肌电生理参数(前静息均值、快肌均值和慢肌均值)。通过多因素Logistic回归分析,筛选出影响术后早期尿失禁发生的独立危险因素,并通过计算受试者工作特征曲线(receiver operating characteristic,ROC)下面积,评估盆底肌电参数的预测效能,再利用约登指数(Youden index)并结合临床意义,共同确定术后早期尿失禁发生的最佳临界值。结果:纳入患者271例,术后自主控尿率为81.9%。患者快肌评分为23.5(18.2,31.6)分,慢肌评分为12.5(9.6,17.3)分,179例(66.1%)患者未保留性神经,110例(40.6%)患者进行了尿道功能重建。高龄和盆底快肌评分低被确认为尿失禁发生的独立危险因素。≤60岁患者是≥70岁患者自主控尿率的5.482倍(95%CI:1.532~19.617,P<0.05);患者的盆底快肌评分与尿失禁恢复的关系密切(OR=1.209,95%CI:1.132~1.291,P<0.05)。当术前盆底快肌评分的最佳临界值设定为18.5分时,ROC的敏感度和特异度分别为80.6%和61.2%。结论:术前盆底肌电生理参数对于前列腺癌术后尿失禁风险表现出较好的预测准确性和临床应用性,能够用于前列腺癌术后尿失禁风险的早期识别,其中年龄和盆底快肌评分是重要的预测因子。

综合干预联合盆底康复治疗对围绝经期女性盆底功能障碍性疾病的影响

目的:探讨综合干预联合盆底康复治疗对围绝经期女性盆底功能障碍性疾病(PFD)的影响。方法:选取2021年10月—2022年12月贵州航天医院收治的160例围绝经期PFD患者作为研究对象,以随机数字表法分为研究组与对照组,各80例。对照组实施盆底肌康复治疗,研究组在对照组基础上进行综合干预。比较两组干预效果。结果:研究组总有效率高于对照组,差异有统计学意义(P=0.043)。干预6、12周后,两组Ⅰ、Ⅱ类肌纤维疲劳度和盆底功能评分逐渐降低,且研究组低于对照组,两组Ⅰ、Ⅱ类肌纤维电压值逐渐升高,且研究组高于对照组,差异有统计学意义(P<0.05)。结论:综合干预联合盆底康复治疗对围绝经期女性PFD的干预效果显著,可改善盆底肌疲劳度、电压值、盆底功能。

盆底超声评估妊娠、分娩和盆底肌锻炼对产妇盆底功能的影响

目的探讨盆底超声评估妊娠、分娩和盆底肌锻炼对产妇盆底功能的影响。方法选择2019年1月至2023年1月我院收治的104例产妇,根据干预方式不同分为对照组(n=50)和研究组(n=54)。对照组给予常规妊娠指导和护理,研究组则在妊娠28周后加用盆底肌锻炼。比较两组产后8周的盆底功能和盆底超声检查结果。结果研究组盆底肌力等级显著优于对照组,压力性尿失禁发生率显著低于对照组(P<0.05)。研究组CD、LHD-d、LHLR-d、RAD、BND显著低于对照组(P<0.05)。结论盆底超声可评估妊娠、分娩和盆底肌锻炼产妇的盆底功能;盆底肌锻炼能够显著改善产妇的盆底功能,减少盆腔结构变化,降低压力性尿失禁发生率。

经会阴盆底超声定量评估围绝经期子宫全切术后近期盆底功能的价值

目的经会阴盆底超声动态观察围绝经期子宫切除术后盆底结构变化,并定量评估其近期盆底功能。方法选择2021年1月—2023年3月在徐州市妇幼保健院超声科因子宫良性病变行子宫全切术后1年内复查的62例患者作为观察者设为子宫切除组,年龄40~55岁,术前未绝经,术前无盆腔手术史,术前临床未诊断盆底功能障碍性疾病(pelvic floor dysfunction,PFD);选择同期在本院经会阴盆底超声检查前临床未诊断PFD的61名女性作为对照组,年龄40~54岁,未绝经,无盆腔手术史。所有检查者均由科室2名盆底研究方向副主任医师随机分配操作检查。所有受检者行经会阴盆底超声检查,在标准切面上测量膀胱逼尿肌厚度、静息状态及最大Valsalva状态下膀胱颈距离耻骨联合后下缘距离(X)、膀胱尿道后角(β)、直肠壶腹最低点距耻骨联合后下缘距离(D),观察尿道内口漏斗形成,计算尿道旋转角(Ra)及膀胱颈下降值(bladder neck descent,BND),并观察前后盆腔有无器官脱垂及程度。结果子宫切除组患者年龄较对照组大,有统计学意义(P<0.05),X、D值均减小,差异均有统计学意义(P<0.05);而Ra、β、BND、膀胱逼尿肌厚度及裂孔面积比较差异均无统计学意义(P>0.05);子宫切除组与对照组发生PFD的情况比较,仅直肠脱垂差异有统计学意义(P<0.05),压力性尿失禁(stress urinary incontinence,SUI)、膀胱脱垂、盆腔器官脱垂(pelvic organ prolapse,POP)总计及PFD总计比较差异均无统计学意义(P>0.05)。结论经会阴盆底超声可对围绝经期子宫切除术后盆底结构动态观察,并进行定量评估;子宫切除术对围绝经期女性后盆腔盆底功能影响较大。

深部矿井软底回采巷道底鼓机理及防治研究

针对山阳煤矿软底回采巷道严重底鼓的难题,采用理论分析、数值模拟和现场应用的方法,基于塑性理论建立了巷道底板岩体滑移线底鼓力学模型。研究表明,巷道底板破坏岩体主要分为3个区,分别为主动极限区、过渡区和被动极限区,推导了巷道底板岩体的最大破坏深度,提出了锚索+卸压槽联合控制底鼓的方法。采用数值模拟的方法验证了联合控制方案的可行性,现场应用效果表明该方法能够有效控制软底巷道底鼓,为相似地质条件底鼓问题的研究提供了一定的帮助。

柱端盖板型滑移摩擦节点分层装配钢框架滞回性能研究

分层装配式钢框架是一种能充分体现快速装配性的新型结构形式。基于低损伤抗震概念,针对柱端盖板型滑移摩擦节点(CPSFJ)分层装配式钢框架的滞回性能进行了试验研究和数值分析。研究发现,通过在柱端设置CPSFJ,可以有效实现在大震作用下以滑移摩擦耗能代替结构构件的塑性损伤耗能,进而保护结构主体构件免受损伤。试验结果表明,该结构体系在低周往复加载下,滞回曲线呈现出饱满的弓形,且骨架曲线表现为三段式平顶型,显示出良好的能量耗散能力和稳定的滞回性能。为解决梁端局部刚度不足的问题,提出了梁端加劲肋布置改进方案,能显著改善梁端应力集中现象,降低塑性损伤的可能性。本研究为分层装配式钢框架结构设计提供了新的抗震耗能方案,具有重要的理论意义和应用价值。